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TER VERKRIJGING VAN DEN GRAAD VAN
DOCTOR IN DE WIS- EN NATUURKUNDE
AAN DE RIJKS-UNIVERSITEIT TE UTRECHT,
OP GEZAG VAN DEN RECTOR MAGNIFICUS
Dr. C. W. VOLLGRAFF, HOOGLEERAAR IN
DE FACULTEIT DER LETTEREN EN WIJS-
BEGEERTE, VOLGENS BESLUIT VAN DEN
SENAAT DER UNIVERSITEIT TEGEN DE BE-
DENKINGEN VAN DE FACULTEIT DER WIS-
EN NATUURKUNDE TE VERDEDIGEN OP
MAANDAG 24 FEBRUARI 1936,
DES NAMIDDAGS TE 4 UUR

DEZE DISSERTATIE VERSCHIJNT TEVENS ALS No. 11 VAN DE PHYSIOGRAPIIISCH-
GEOLOGISCHE REEKS DER GEOGRAPHISCHE EN GEOLOGISCHE MEDEDEELINGEN

ü, Hoogleeraren der Wis- en Natuurkundige Faculteit,
dank ik hierbij zeer voor dc vriendelijkheid en het
geduld, waarmee U mij gedurende mijn studietijd
steeds voortgeholpen hebt. In het bijzonder geldt
dit natuurlijk mijn Vader en Promotor.

General, age, spilites, diabases and porphyrites,
spilite problem, tuffs and cherts.

General, age, serpentines s. s. Other rocks,
general, gabbroid dikes, foreign enclosures,
slightly metamorphosed group, meso-zonatic
metamorphosed group.

General, age, diorites s. s., diorite-porphyrites,
leucocratic dike-rocks, melanocratic dike-rocks,
contact metamorphism.

General, age. Southern facies : general, diffe-
rences with the Tuff Series, intrusions of por-
phyrites, petrography. Northern facies.

Orogenetic phases, difference between northern
and southern part, discussion of the thickness
of different formations.

Dictyoconus fontabellensis (Vaughan),
Vaugbanina cuhcnsis Palmer,
LepidocycUna sitpera (Conrad),
Monticulastrea regularis Kühn,
Diplochaetetes longitnhus Weissermel,
Nerinea cf. hkincta Bronn.

East of Santa Clara, La Movida — Bonachea,
T.a Movida — Santa Fé, Santa Fé — Carretera
Central, Camajuani — Falcon, Camajuani —
Placetas.

La Esperanza — San Diego del Valle — Cifuen-
tes — Sagua la Grande — Quemado de Guines 52

The country South from the Carretera Central,
between Santo Domingo and La Esperanza.... 54

This paper describes the geology of the northern part of the Province
of Santa Clara in middle Cuba. The boundary towards the South is drawn
over Central Caracas, Guayos, San Juan de los Yeras, Central Pastora,
Provincial, Baez, and at the crossing of the Rio Calabazar with the Carretera
Central.

The fieldwork was done, and the material collected, during an expedition
from the University of Utrecht, Holland, under the leadership of my father,
Prof. L. M. R. Rutten, with six members, Mr. H. J. Mac Gillavry,
.A'fr. A, A. Thiadens, Mr. L. W. J. Vermunt, and the author, all students
of geology at the Utrecht University; Mrs. C. J. Rutten-Pekelharing and
Miss A. Röntgen.

We worked in Santa Clara province during the second half of February,
the whole of March, and the first half of April of the year 1933, during
which time we surveyed both the northern and the southern part of the
province. All material, notes and samples, bearing on the northern half of
the province were turned over to me, to compile a geologic description
of this district. Air. A. A. Thiadens will describe the southern part of
the province.

Maps : We had at our disposition the mihtary Cuban maps on the
scale of one inch to a mile, whilst at home we could make use of the maps
of the Carretera Central a new highway over the axis of the island, and
the nautical charts of the American Navy.

The Cuban military maps were very bad, and not to be relied upon.
Instead of these we surveyed our own courses by taking directions with
an ordinary hand-compass and measuring distances by counting our paces.
The rough maps got in this way were more reliable than the official Cuban
maps. At home, the differentquot; courses were plotted, and put into position.
As can be seen from the map I had the disposition of numerous triangles,
and with the help of these I could correct major differences between various
courses. The maps of the Carretera Central, at the scale of one to twenty
thousand, proved reliable enough as to distances and directions, although
sometimes the North-indication was wrong. The nftip thus obtained, could
be controlled with the U. S. Navy chart, as both La Isabella and Caibairien
were indicated on the chart. The distance between La Isabella and Caibairien
on my map was 3 % the smaller, which could be corrected by a shght
change in direction of the long, straight road from Sagua la Grande to La
Isabella. For publication with this paper two different maps were prepared,
one to show the geology, the other to indicate the localities and find-spots

mentioned in the description of the district. For the sal^e of an easy compa-
rison of both maps, the geologic boundaries are drawn on the second map
also. For the geologic map we had to choose between two ways of indicating
our observations. The area surveyed is by no means covered by obser-
vations, but we surveyed a number of sections only, these form together
a maze with openings of varying width. I could have indicated only the
geology along the courses surveyed, e. g., the results of direct observation.
This was not done, as, during our field-work and the latter period of labo-
ratory work, we got a definite conception of the geologic structure of the
district, and by this interpretation could, with a certain measure of security,
combine the boundaries and other data found at the individual courses and
so make a geologic map, covering the larger part of the area surveyed.
The geologic map published with this paper thus is the combined result
of direct observations and their interpretation. To show the amount of
direct observation, and to show the widths of the openings the maze of
observations leave, all courses surveyed are indicated on both maps, so that
everyone can see at a glance if certain features are only interpretation, or
also supported by direct observations. As this was the first detailed geologic
description of the northern part of Santa Clara Province, it was thought
necessary to give also a find-spot map, together with a detailed description
of several of the major courses, thus producing definite controllable evidence
for the statements made in the general part of the paper.

A difficulty arose, with the recording of the different strikes and dips
on the geologic map. In the heavier and more irregularly folded regions
it was impossible to draw all strikes and dips observed, and only a certain
number could be selected, the selection of course being wholly subjective.
Possibly the abnormal strikes, occuring in the field only in a small number,
are reproduced in a relatively larger number on the map. This is not, however,
of vital interest, as, with the scarce and widely apart courses surveyed, we
did not succeed in finding a definite structure in these heavily folded regions,
so that no statements about the structural build are deduced from the
relative importance of the regular or abnormal strikes.

Acknowledgments: I am indebted for help and advice of various
kinds to a.large number of people.

The 'Molengraaff-fonds' and the 'Bataafsche Petroleum Maat-
scHAPPij' gave financial support to our field work.

I have been largely helped by the fact that all observations and field
work done in the district by the other members of the expedition were
placed at my disposition, whilst, during the working out of the Rudist
collections made, I had much help from Mr. H. J. Mac Gillavry's extensive
knowledge of this subject.

At Cuba the Government and the Sociedad Geografica de Cuba have
furthered our interests in every possible way, and we shall long remember
the agreeable help of Cuban private residents, especially the ever-active
interest and aid of Tngenior Félix Malberti. Mr. Poliakoff, of the

Compania Shell Mex, has also been of great assistance to us, whilst the
long discussions on Cuban geology we had with Dr. Tschopp, geologist
of the Shell Mex., in the field, were of vital interest for our studies. To
Dr. Tschopp I am furthermore indebted for the fossil locahty H. 550,
between La Esperanza and Santa Clara, where many beautiful Rudists
were found.

To Prof. Trauth of Vienna and Prof. Jaworski of Bonn, I am
indebted for their assistance, they having taken over the separate study
of our collections of Aptychi and Ammonites.

Mr. van Dijk of the Utrecht laboratory executed .ill drawings and
micro-photographs necessary for the publication of the paper with pain-
staking accuracy and neatness.

My cousin Mrs. Breuning-Williamson kindly revised with me the
English text of the manuscript.

To Prof. J. L J. M. Schmutzer I am indebted for his careful revision
^of the microscopic thin-sections, and to Mr. W. van Tongeren for the
making of the chemical analyses and advice in petrochemical matters.

Prof. H. Gerth, of Amsterdam determined the corals found, and
kindly permited me to publish the results in this paper.

The district described, the northern part of the Province of Santa Clara,
middle Cuba, is formed by a structural high, and bounded at the western
and eastern side by large synclinoria, with the younger sediments chiefly
exposed.

Geologic history begins in Lower Cretaceous times, with.the sedimen-
tation of the Aptychi Limestones and the lower parts of the Tuff Series.
These two elements are of the same age, and only form different facies. But
whereas the Aptychi Limestones only contain fossils of I.ower Cretaceous
age, the Tuff Series are found to range higher up in the geologic column,
and locally contain fossils of lowest Upper Cretaceous (Turonian-Emscherian)
age. Generally speaking, we find the Aptychi Limestones in the northern
and eastern part, and the Tuff Series in the southern part of the district.
The difference is, however, gradual, and a close alternation of layers of the
different facies has been observed. The Tuff Series comprises volcanics
— spilites, diabases and porphyrites, with glass-tuffs, crystal-tuffs and tuff-
breccias of the same composition — and cherts, sometimes with Radiolaria.
Limestone-beds are sometimes intercalated, and rarely macro-fossils — Am-
monites or Caprinids — are found. The Aptychi Formation is formed by
greyish, monotonous, well bedded limestones, and intercalated cherts.
Locally they carry abundant Radiolaria- or Smaller Foraminifera. Scarce
macrofossils found comprise remains of Ammonites and their Opercula.
Specific determination of these Opercula places the Aptychi Limestones
into the Lowest Cretaceous.

Following the sedimentation of these formations came orogenetic
activity, with the intrusion of large masses of peridotites, and slightly
younger dikes of gabbroid composition, followed by the intrusion of dikes
from a dioritic magma. The peridotites nowadays are found as large and
smaller massifs of Serpentine. Within the Serpentines we find many foreign
inclusions that may be divided into two groups. The first group shows
only slight metamorphism, and comprises diabases and spilites, closely allied
to and derived from the Tuff Series. To the second group belong schists,
amphibolites and garnet-rocks, with a meso-zonatic metamorphism, that are
parallelised with older, jurassic, schists, known from other parts of the island.

In the Uppermost Cretaceous, parallelised with the Maastrichtian of
Europe, there followed the sedimentation of the Habana Formation. In the
southwestern part we find limestones, tuffaceous limestones and tuffs,
indicating a continuous volcanic activity, with a characteristic fauna of
Orbitoids and Rudists. In the northern and eastern part we find mostly

Time:

northern facies:

Guines Limestone.

Oligo-Miocene

Gentle folding.

Orogenesis

4-1

V.1

Oligocene

Upper Eocene

Gentle folding.

Orogenesis

Habana Formation
Limest. with Orbitoids
and Rudists, tuffaceous
limest., glass-tuffs, in-
trusions of porphyrites,
basal conglomerate.

Maastrichtian

Gentle folding.

Orogenesis

Intrusion of peridotites with inclusions from the
Tuff series and from older formations, at present
unknown in the district.

00
d
o

lt;73

Spilites, diabases, porphy-
rites, glass-tuffs, crystal-
tuffs, tuff-breccias, cherts,
Radiolaria, Ammonites.

Lower and

Middle

Cretaceous

Aptychi Limestones.
Limestones, cherts, Ra-
diolaria. Smaller Forams.,
scarce Ammonites and
Aptychi.

brcccia-limcstones, sometimes with characteristic Orbitoids or Rudists, and
a much smaller amount of volcanics.

Between the Maastrichtian and the Upper Eocene a second orogenesis
took place, followed by the sedimentation of the Upper Eocene and Oligo-
cene beds. In the southwestern part we find marls and limestones, occa-
sionally conglomeratical or with tuffaceous elements, that are transgressive
with a basal conglomerate over the older formations. The fauna comprises
locally abundant Larger Foraminifera, Radiolaria and several corals. In the
northern fades marls and fine-grained oolithical limestones are found,
the fauna mainly comprising Smaller and Arenaceous Foraminifera, locally
with Radiolaria.

Following the sedimentation of the concordant Upper Eocene and
Oligocene beds, came a third orogenetic phase. In the southwestern part
it resulted in the formation of gentle, undulating, structures, in the
northern and eastern part the Upper Eocene beds were heavily folded,
and synclines with monoclinal build were formed.

The horizontal Guines Limestone of Oligo-Miocene age marks the end
of the orogenetic activity in the district.

It must be noted that the difference in facies found in the Lower Cre-
taceous Tuff Series and Aptychi Limestones, roughly characterised by a
decrease of volcanic matter towards the North and East, is also found with
the younger formations.

Parallel to this difference in facies is a difference in tectonic style. In
the southwestern part we find simple, large structures, that are replaced
towards the North and East by an imbricate structure, formed by narrow
wedges bounded by overthrusts. These are found mainly at the contacts
of the Serpentines with the Tuff Series or Aptychi limestones.

General: From the map we may see, that this formation is found,
for its larger part, to the South of the Serpentine-belts. In an uninterrupted
zone, it runs along the southern boundary of the district, from San Juan
eastward. We find it here in its typical facies, being built up by volcanics
and cherts. More to the North, we find it again, closely associated with
the limestones from the Aptychi Formation. South from Camajuani for
instance, we find the rocks from the Tuiff Series with occasional intercalated
' beds of limestone, not to be distinguished from those of the Aptychi Forma-
tion, and South of San Andres we find Aptychi Limestones closely alternating
with layers of tuffs and porphyrites, in the neighbourhood of M. 479.
Moreover at L. 535, between Bernia and Santa Clara, and at M. 604, West
of Placetas, well bedded Ammonite-bearing limestones are intercalated
between rocks from the Tuff Series.

The Tuff Series consists largely of green or greenish rocks and thereby
is easily distinguished in the field. We find spilites, diabases and porphyrites,
with tuffs — occasionally brecciaceous — and cherts. Spilites and diabases
are mostly without any trace of bedding, the porphyrites may occur in
rather thin sills or lava-sheets ; the tuffs and cherts are well bedded.

Age: Although the only fossils commonly found in this formation are
the Radiolaria from the cherts, we may safely assume a Lower Cretaceous age
for its lower parts, from the interbedding at various localities of Tuff Series
and Aptychi Limestones. But, in contrast with the Aptychi Limestones,
where the fossils found all indicate a Lower Cretaceous age, the Tuff Series
ranges higher up in the geologic column. This is proved by the Ammonites
found at M. 604 and L. 535^ which, according to Prof. Jaworski can not
be parallelized with those from the Aptychi Limestones, but are of lowest
Upper Cretaceous (Turonian-Emscherian) age; and also by abundant rests of
Caprinids, found just South of the district on the road from Santa Clara
to Manicaragua, in limestones intercalated in the Tuff Series. The Ammonites
will be described separately by Jaworski, together with other Ammonites,
collected on the island by us, and the Caprinids will be described by Mr. A.
Thiadens, in his description of the southern part of Santa Clara Province.

Spilites: The spilites are mostly very weathered and difficult to sample.
Less weathered specimens are green to dark green, fine grained rocks. Micro-
scopically they consist of acid felspars and augite, with their decomposition
products ; together with magnetite in fine grains or small crystals. The
felspars form short laths, not exeeding 0,3 mm. They are strongly clouded

by very small inclusions; too small to determine their nature, and vary
in composition from albite-oligoclase to oligoclase-andesine. Most laths
are twinned, without, however, forming lamellar twins.

They are grouped irregularly, lying in all directions. In the places
between the felspar-laths lie small and large grains of augite with an occasio-
nal larger crystal, thus making the texture of the rocks truly ophitic. Mostly
the amount of felspar is much larger than that of augite but in some cases
they are almost equal. The felspars decompose into zeoHtes (mainly prehnite)
and zoisite or chlorite, whilst also sericitisation occurs. The augites are
transformed to green, fibrous amphiboles, thereby forming uralite-spilites.
The amphibolc is altered into chlorite, which mineral also originates directly
from the augites, and sometimes the aggregates of chlorite are altered into
secondary quartz. Between Guaracabulla and Placetas we found spilites
that differed in texture from the common type, and were formed by small
felspar-laths placed in beautiful spherolites with many very small grains
of augite, irregularly strewn between the felspar-spherolithes. Several rocks
show transitions toward the porphyrites. The texture becomes coarser,
with phenocrysts of plagioclase. The felspar, however, is cloudy, with an
albite-oligoclase composition, contrasting with the more calcic felspars
from the diabases and porphyrites (see pi. I, fig. 1).

Diabases and Porphyrites: The diabases and porphyrites mainly
are harder, less weathered, rocks. When in the neighbourhood of bedded
tuffs or cherts, they are seen to occur in concordant beds. Pillow-structure
is met with sometimes, but not predominant. The rocks are mostly green,
fine-grained, crystalline, with small white spots from the felspar-pheno-
crysts. Sometimes their colour varies to brown or grey. Microscopically,
they consist of felspar and augite, with magnetite in small crystals always
present in a small quantity, and sometimes apatite. The porphyrites grade
into coarse diabases and normal diabases, by a gradual diminishing in size
of the phenocrysts, whilst the intersertal texture of the groundmass becomes
coarser. Diabases and most porphyrites are holocrystalline, but porphyrites
with vitreous groundmass also occur. Phenocrysts are formed by clear,
twinned felspars; of a composition that varies from labradorite to bytownite;
and colourless augites. Both components are also found in the crystalline
groundmasses. Occasionally we find crystals of a light-brown to greenish-
brown pleochroitic amphibole.

The felspars decompose into zeolites, chlorite or zoisite, and the augites
are often altered to green fibrous amphiboles, thereby forming uralite-
diabases and uralite-porphyrites; or to green, irregular, aggregates of
chlorites.

Spilite Problem: The relation of the diabases and porphyrites with
a true gabbroid composition to the more acid spilitic rocks is not clear.
As the spilites are always more weathered than the porphyrites, with a
larger amount of secondary minerals, we might consider them as normal
decalcified diabases. In favour of this view is the fact, that we find some

cases, where the clear calcic felspars of the porphyrites show more cloudy
patches that also have a more acid composition, thus indicating a decompo-
sition from the clear calcic felspars of the porphyrites toward the cloudy
acid felspars of the spilites. On the other hand the felspar-laths of the spilites
are almost invariably twinned, which seems unreasonable in a secondary
mineral, and we also may ask why the spilites should have their plagioclase
decomposed, whilst the porphyrites and diabases with which they alternate
have unaltered felspars.

The literature on the problem is rather large, and views as to the origin
and even as to the definition and limits of the term 'spilite' differ widely i).
I cannot say anything definite as to the causes which led to the formation
of the Cuban spilitic rocks. I have used the term to denominate rocks with
a diabase-like habit, differing from the true diabases by their acid felspars.
If used in this sense, the term comprises rocks, that for the greater part
have the same geological habit and environment, and are widely met with
' in the Cretaceous of the Antillean region.

Tuffs and Cherts: The tuffs range from coarse, somewhat brec-
ciaceous, elements; with fragments of porphyrites and phenocrysts; over
finer grained crystal-tuffs to glass-tuffs. These often carry Radiolaria, that
sometimes become abundant, or get silicified, thus grading towards Radio-
/(?m-bearing and Radiolaria-he.e. cherts.

The bedding, that is bad in the coarser porphyrite-tuffs, improves as
the sediments become finer grained, and is good with the finely-bedded
cherts. The coarser tuffs are built up almost entirely by fragments of crystals
and rock, carrying very little cement which gives them a brecciaceous
appearance. Glass as cement increases with the decrease of the dimensions
of the constituents, whilst it predominates in the glass-tuffs proper, that
carry only a small amount of crystal-fragments, of diminutive dimensions.

The coarse crystal- and porphyrite-tuffs are generally heavily weathered,
greenish in colour, weathering to brownish-green. Sometimes we find
fresher rocks, with lighter (grey or brown) colours. Microscopically, they
are seen to vary over a wide range and to carry constituents, we can paral-
lelize with both the spilites-, and the diabases and porphyrites. Principal
among the fragments of phenocrysts are felspars. Some rocks carry cloudy
specimens, which have an acid composition of albite-oligoclase; whilst in
other rocks clear calcic plagioclases are found ; showing beautiful lamellar
twinning or zonal structure, and with a composition that varies from labra-
dorite to bytownite. As a rule we find the acid cloudy felspars with the
weathered soft rocks, and the basic types with fresher and harder rocks,
but exceptions of this rule occur. We find other crystal-fragments of colour-
less augite, of magnetite and sometimes of a light-brown to greenish-brown
pleochroitic amphibole. The fragments of porphyrites found in the coarsest

1) A discussion of the literature of this subject can be found in 'Keratophyres of eastern
Oregon and the spilite problem'. By Gilluly, J., in the American Journal of Science, Fifth
Scries, XXIX, 171, 1935.

tuffs, the porphyrite-tuffs, are lumps of groundmass from true porphyrites,
with small laths of clear, basic, felspars, with much glass in some cases,
or with grains of augite, placed intersertally, in other cases.

As in the extrusive rocks, the clastic tuffs often have their components
strongly altered. The felspars then undergo chloritization, zoisitization and
sericitization, whilst the pyroxenes are altered into uralite or chlorite.
Moreover in several cases calcitisation is apparent.

The glass-tuffs are dark-green rocks, weathering to a brownish-green
colour. Their structure is dense, dyscrystalline, and in the field they are
friable, soft, mostly rather strongly weathered. Microscopically they consist
of dusty glass, mostly clouded by minute, or slightly larger, inclusions of
chlorite and limonite. Its refractive index is always lower than 1,54. Small
angular fragments of felspars, of varying composition, are included in varying
amounts and sometimes, if the amount of felspar-fragments is high, we
find occasional fragments of augite. They often contain remains of Radio-
laria; even globular forms with diameters varying from 75 to 200 ja.

They grade into the well bedded, dense, hard, green or bluish black
cherts, that often carry Radiolaria and sometimes are almost built up by
these fossils.

General: This formation is mainly found in the northern and eastern
part of the district, where it usually forms the ridges of low hills that cross
the country with a general Southeast—Northwest strike. It is called Aptychi
Formation or Aptychi Limestones, as it is for the larger part built up by
greyish limestones and marly limestones, that in several localities contain
ammonite Opercula, and sometimes remains of Ammonites.

The collections of Opercula made by us in this and other parts of the
island were sent to Prof. F. Trauth, of Vienna, who was so kind as to
determine them specifically for us (Bibl. 13). The collections of remains
of Ammonites were sent to Prof. E. Jaworski at Bonn, the results of his
determinations will be published in due course.

Age: According to Trauth, the ammonite Opercula found all indicate
a Lower Cretaceous age for the Aptychi Limestones, which view is also
held by Jaworski, after a preliminary examination of the ammonite re-
mains (Jaworski, in litt.).

Petrography: The Aptychi Formation is built up largely by limesto-
nes and, to a much smaller extent, by cherts, whereas locally marls and
sandstones, or intercalated layers of tuffs occur. The limestones are mono-
tonous, dull, grey or greyish-blue, sometimes reddish, dense, and well-
to finely-bedded. Intercalated are layers and lenses of dark dense cherts
In some localities occur grey-brown, fine-grained, sandstones, built up by
fragments of crystals of clear quartz, basic plagioclase felspars and muscovite
m small tabular crystals, with rarely some fragments of micropegmatitic

quartz-felspawntergrowths. The components of these sandstones resemble
those of the Diorite-intmsions. We might surmise that they were formed
by detrition of these Diorites, but abundant evidence proves the Diorites
to be younger than the Tuff Series and the Serpentines. So the components
of these sandstones are derived from older sources, perhaps from the equi-
valents of the Pinar schists, from Pinar del Rio, or the schists from the

Sierra de Trinidad, in southern Santa Clara, which carry a considerable
amount of quartz.

Fauna: The only macro-fossils found are Ammonites and their
Operada. The Aptychi are scarce and the Ammonites are rare the state of
preservation of the Ammonites is bad. The fossils are usually found at
places, where the limestones are very finely-bedded, and not in the coarser
banks. Besides these we locally find abundant micro-fossils. In some rocks
Smaller Forammfera, mostly related to the genus Globigerina are found in
. abundance, but usually the Radiolaria are the commonest, and also found
m more locahties. We found radiolarian cherts and limestones. In the last-
mentioned rocks the silica of the radiolarian-tests has been completely
replaced by calcite. Remains of plants occur sometimes, but arc no-
where predominant.

Facies: The facies of the formation, characterised by the fine-grained
or dense, well-bedded, monotonous layers, and the occurrence of 7\mmo-
nites and ammonite Opemda as the only macro-fossils suggest a deep-sea
sedimentation.nbsp;^

Palmer (8) reaches the same conclusion, but states that the sedimen-
tation must have taken place well within the continental shelf bccausc of
the occurrence of plant remains in the formation. These might be transported
over larger distances by former sea currents, but the sandstones found
intercalated at different localities in the Aptychi Limestones also indicate a
sedimentation close to adjacent landmasses. The Radiolaria and Glohigerina
found do not give a definite indication, so the evidence available points
to a sedimentation of the rocks in a deeper sea, well within reach of
former landmasses.

The monotony of the stratigraphy, coupled with the scarcity of macro-
fossils makes it impossible to distinguish index horizonts. The beds of this
formation are usually strongly and irregularly folded and faulted and the
absence of index horizonts made it impossible to find anything definite as
to the internal structure of the lime-stone ridges.

Différé nces with the Tuff Series: As has been stated before
the Aptychi Limestones are a facies-cquivalent of part of the Tuff Series!
The Tuffs arc mainly built up by volcanics and cherts, and the Aptychi
Formation by limestones and cherts. The difference is, however, a gradual
one, as we find intercalated layers of tuffs in the Aptychi Formation and
also limestone beds in the Tuff Series. Moreover, we often find a small
amount of volcanic matter within the limestones of the Aptychi Formation,
consisting of small angular fragments of plagioclase felspars, so that we

find evidences of volcanic activity in the northern facies also. The Caprinids
found intercalated in the Tuff Series, South of Santa Clara, indicate a littoral
sedimentation of the Tuff Series. The facies of the Aptychi Limestones thus
differs from that of the Tuff Series by a very considerable — in many layers
even a total — reduction of the volcanic matter, together with the sedimen-
tation taking place in deeper water. This feature explains the monotony
of the beds of the Aptychi Formation, contrasting with the irregular and
varied sediments of the Tuff Series.

General: Serpentines and associated rocks form one of the common
features of the district and are mainly found in its central part. Although
sometimes occurring in large, unbroken territories e. g. in the Sierra Alta
de Agabama southeast of Santa Clara ; and in the country between Santa
Clara and Encrucijada, we find them also in narrow strips, outcropping
between other elements and following their general structural trend. The
Serpentines are dark-greenish rocks, with many veins of lighter-green rocks,
with veins of carbonates, with abundant foreign inclusions, comprising more
or less altered igneous rocks and strongly metamorphic schists, and with
dikes of younger intrusives. The country where Serpentines are exposed,
is readily recognised by its vegetation, which varies from almost nil to
so-called sabanas, badlands, with typical palms and a thorny undergrowth.
The rocks usually are well exposed and not weathered.

Owing to the low elevation of most of the country under discussion,
no natural sections, offering views of the contacts of Serpentines with the
other formations, were found. In several places, however, we see how the
boundaries between the Serpentines and the other formations, cut across
the bedding in these formations, indicating a tectonical contact. This is
the case to the North and South of the Sierra Alta de Agabama, at L. 619,
and East of Provincial. In other placec, traces of asfalt or oil at the contact
between the Serpentines and other formations, also indicate a tectonical
contact. For instance near Santa Clarita and at the asfalt mine Anna Maria,
Southwest of Placetas. Finally we find direct evidence of a tectonic contact
between Aptychi Limestones and Serpentines at H. 423 and H. 535, East of
Santa Clara, where a limestone-serpentine-breccia is formed at the contact
between the two formations (See p. 13, fig. I; pi. I, fig. 2); and in the Ser-
pentine-zone South from Camajuani, which is here so. heavily sheared, as to
simulate a stratified structure parallel to the contacts between the Serpen-
tines and the other formations. With these evidences of a tectonic contact
between Serpentines and older formations at many places, I assume that
everywhere, where we find in this district a sharp boundary-line between
these formations, without any indication of contact-metamorphism the
contact IS a tectonical one, formed by overthrusting. The only locality
where this seems not to be the case is North from Santa Clarita Here

until we reach M. 374 ; where no Serpentines are found any longer and
only porphyrites and diabases from the Tuff Series are exposed.

Age: In the geologic column, the Serpentine rocks are placed above
the Tuff Series and their equivalent the Aptychi Limestones, and under
the Diorites and Habana Formation. Evidence of this age runs as follows.
As seen above, near Santa Clarita, the Serpentines are in contact with the
rocks from the Tuff Series and carry inclusions from this series. These
inclusions arc slightly metamorphosed, we find here uralite-diabases, con-
trastmg with the diabases with unaltered pyroxenes, found at M. 374,
within the Tuff Series proper. Although this is the only place, where we
find metamorphosed rocks from the Tuff Series close to the contact between
Serpentines and Tuff Series, more or less metamorphosed rocks from the
Tuff Series are found within the Serpentines at many other localities.
In these cases the geographical relationship to the Tuff Series is not so •
clear, but the pctrographical relationship is apparent. These rocks comprise
more or less uralitized spilites and diabases that can not be distinguished
petrographically from the uralitized rocks, found within the Tuff Series
itself, whereas spilites and diabases, showing stronger uralitization, are also
found as inclusions within the Serpentines, together with true uralite-rocks,
where uralite and some chlorite have replaced all other mineral consituents!

The Serpentines are older than the Diorites, as we find, along the
Carretera Central between Placetas and Falcon, several dikes of dioritic
rocks in the Serpentines, here clearly exposed in cuts made for the new
highway, the Carretera Central.

^^^ Serpentines, with inclusions of diabases from
the Tuff Series at M. 371 ; which inclusions increase in number and volume

In numerous other places in the country we find Dioritic rocks within
the Serpentines. The largest patches are those along the Carretera Central
between La Esperanza and Santa Clara and in the hills direct Southwest
of the town of Santa Clara. Here we do not actually see that these rocks
are intrusive in the Serpentines, but may assume so, when we take into
consideration their dike-like form of occurrence, in small patches, together
with the fact, that the dioritic rocks do not show any signs of metamorphism
other than shearing, due to tectonical stresses. The Serpentines thus are
older than the Diorites which most probably intruded in Upper Creta-
ceous times, just before the sedimentation of the Habana Formation during
the Maastrichtian. No pebbles of Serpentine were found in either the Habana
Formation or the Upper Eocene, but this may be due to the small amount
of resistance given by Serpentine to the forces of erosion, as we find
pebbles from the harder, and more resistant foreign inclusions, both in
the Habana Formation near Santa Clarita and Falcon, and in the basal
conglomerate of the Upper Eocene, East of Santa Clara and West of
Conyedo.

Serpentines s.s. : The serpentine-rocks proper are practically all of
'Schillerfels'-habit, dark-green, with greasy glance, showing large patches
of bastite. Under the microscope they appear to consist of antigorite, which
has its short fibres arranged in small quadrangular, or rectangular, patches.
These patches may be rather regularly arranged. Between the antigorite
we find large even fields of bastite. Magnetite is always present, often in a
considerable amount, in very small grains arranged along the contours
of the antigorite-quadrangles, accentuating their structure by thin black
lines formed by many small grains of this mineral. The serpentines have
clearly originated from harzburgites, the olivines being decomposed to
antigorite with a residue of magnetite accumulating along the cracks of
the olivine-crystals, whilst the rhombic pyroxenes are altered into the
patches of bastite. We did not succeed in determining exactly when the

Other rocks: With the Serpentines, we always find foreign rocks :
older inclusions and younger dikes. The inclusions from the Tuff Series
and the dikes of Dioritic rocks have been mentioned already, and the diffi-
culty of determining, if a rock is really intrusive, has been stated with the
discussion of the Dioritic dikes. One only finds sections through the Ser-
pentines along some of the railroads and along the Carretera Central.
Otherwise, the country is not very accentuated and slopes are smooth.
Although no weathering residue of any importance covers tlie rocks in a
Serpentine area, and we find the bare rock exposed almost everywhere,
we never see deeper than the surface rock. In most cases the safest way
to determine if a given rock is an inclusion or a dike, is by way of microsco-
pical examination. As a rule the inclusions have either undergone conside-
rable metamorphism, or can be compared with known rocks from other
formations of this region, whilst the dikes are not metamorphosed; and

have only, in various cases, been sheared to a certain extent through
tectonic stresses.

We find dikes of two kinds. Firstly those, belonging to a dioritic magma,
that are also found as dikes in the Tuff Series, and will be reviewed separately,
and secondly dikes from a basic gabbroid magma that are only found within
the Serpentines. These last vary from gabbro, through olivine-gabbro, to
peridotitic rocks, as harzburgite, Iherzolite and diallage-peridotite.

Gabbroid dikes: The gabbros are white and green medium-grained
crystalline rocks, that contain clear lamellar-twinned felspars, of a composi-
tion varying from labradorite-bytownite to bytownite, and large and small
crystals of beautifully cleaved diallage. Locally either of the two constituents
show their own crystallographic forms, but mostly both have a granular
appearance, whilst the dimensions of the individual crystals of both consti-
tuents vary widely. Occasionally we find poicilitic brown amphibole in
'large crystals without any crystallographic limits, and in the oJivine-gabbros
large and small crystals of olivine are added. Afagnetite is always quot;present
in a large number of small crystals, apatite is rare. Alost rocks are fresh,
with unaltered constituents, but sometimes alteration is commencing. This
is indicated by a serpentinisation of the olivines, a uralitisation of the diallage
and a zeolitisation or sericitisation of the plagioclases. Quartz and chlorites
may also be formed.

The more basic dikes, occurring in a much smaller number, are green
and black, fine to medium-grained rocks, mainly differing from the serpen-
tines by the lack of the greasy glance. They are peridotites, with several
kinds of pyroxene-minerals, thus harzburgites, Iherzolites and diallage-
peridotites are found. On microscopical examination, all show a beginning
of serpentinisation of the olivines, along the irregular cracks through
these crystals.

The age of these dikes must be younger than that of the serpentinisation
of the largerquot; areas of peridotites, as the olivine-crystals from the dikes show
only the beginning of serpentinisation. On the other hand, the fact that
we only find these dikes, within the present geographic distribution of the
Serpentines, indicates that their intrusion occurred before, or with, the
beginning of the stronger tectonic disturbances. We saw before how the
boundaries between the Serpentines and the older formations, are largely
of a tectonical nature and formed by overthrusts. These thrusts alter the
geographic place of the formation-boundaries, and if the intrusion of the
gabbroid-peridotitic dikes had followed the overthrusting, we should expect
them to intrude sometimes on the wrong side of the boundary also. Another
argument for the pre-orogenic age of these dikes is the fact, that we
found within the Serpentines several amphibolites, differing from the more
common amphibolite-inclusions carrying albite and epidote-zoïsite. The
first mentioned amphibolites are formed by basic plagioclases, with diallage
and occasional brown amphibole in allotriomorphic granular structure,
showing, however, strong linear foliation with occasional sutured texture

of the constituents. These amphibolites clearly have originated from the
gabbroid dikes through shearing under orogenetic forces.

Foreign inclusions: The foreign inclusions can be divided into
two groups, those that have undergone slight metamorphism, the products
formed reaching not deeper than the epi-zone, and those that are more
strongly metamorphosed, with products belonging to the meso-zone.

In the field, the rocks from the second group are the most apparent
and consist for a large part of schists, that occur locally in large masses,
extremely plicated and foliated, and without any connection with the sur-
rounding Serpentines. The other components of the second group, chiefly
the non-schistose amphibolites and pyroxene-rocks, although of common
occurrence, are not so often met with, nor do they give the Serpentine-
country such a striking appearance as do the schists. The dimensions of
these inclusions vary widely, from little fragments of several cm. to large
packets of several tenths of meters, whilst in the Sierra Alta de Agabama,
Southeast of Santa Clara, small hill-tops may be entirely formed by the
more resistant foreign inclusions.

The division made in epi-zonatic rocks and meso-zonatic rocks also
holds true in relation to the origin of the inclusions. In the first group we
find the more or less uralitized volcanics, parallelized with rocks from the
Tuff Series, whereas the rocks from the second group have no obvious
connection with other rocks from the district, and must have originated
from a deeper underground, at present unknown in the district.

Slightly metamorphosed group: In this group are reckoned
uralitized spilites, diabases and porphyrites, with occasional uralite-tuffs,
ranging into uralite-rocks, where green fibrous amphibole with chlorites
have almost completely replaced the primary mineral constituents. The
spilites are greenish, either fine-grained or dense rocks, which on micros-
copical examination appear to consist of acid plagioclase felspars and secon-
dary minerals, of which uralite is always present.

The felspars, in short laths that lie irregularly in all directions, are very
cloudy and have an acid composition, of albite or albite-oligoclase. The
green, fibrous uralite is here no longer confined to the spaces between the
felspar-crystals, but its broom-like bundles often grow across the older
crystal-limits. Other secondary minerals commonly found are prehnite or
zoisite and epidote, formed out of the felspars, chlorites and quartz. The
uralite-diabases and uralite-porphyrites, distinguished by texture only, often
have much clearer and more basic plagioclases. These are however subject to
decalcification also, as we find crystals with a clear basic core and a cloudy,
acid outer layer. Here also we find th^ pyroxenes completely altered into
green fibrous uralite, whilst prehnite and sometimes secondary quartz are
common minerals also, and chlorite, epidote, and zoisite have been found.
On three occasions we found green, uralitized, chloritized and silicified
inclusions which under the microscope show a clastic structure and are
considered as altered tuffs. The rocks from the first group, with low

metamorphism can thus be parallelized with rocks from the Tuff Series; In
fact the more uralitized members we find with the Tuff Series can not be
distinguished petrographically from the uralite-spilites and diabases found
as inclusions in the Serpentines. We may attribute this uralitisation to a
regional metamorphism, which attacked both Serpentines and Tuff Series.
In some cases this was accentuated by low contact-metamorphism and this
led to the forming of heavier uralitized rocks. This contact-metamorphism
has always been very gentle, otherwise we should find inclusions from the
Tuff Series with a stronger metamorphism, and the outer layers of the
inclusions would show a metamorphic aureole. This feature was nowhere
observed.

Meso-zonatic metamorphosed group: The inclusions which show
stronger metamorphism — which metamorphism is found throughout each
inclusion, without any indication of a metamorphic aureole even in the
largest inclusions found — must have been metamorphosed already to a
meso-zonatic grade before they were included by the peridotites. For the
metamorphism brought about by the peridotites is low, and cannot reach
a meso-zonatic grade as is demonstrated by. the Tuff Series inclusions. If
we therefore want to compare them with autochthone rocks from the
neighbourhood, only formations, with regional, meso-zonatic metamorphism
are to be considered. We find such rocks in the schists from the Isla de
Pinos, described in detail by L. Rutten, (10) and in the Sierra de Trinidad
in the southern part of the Province of Santa Clara. It is probable that the
rocks from the second group have originated from a formation in the
deeper underground of the province, which is the equivalent of the schist-
formations mentioned.

In this group the most common rocks are various schists and amphi-
bolites, mostly carrying albite, epidote or zoisite, whilst also eclogites and
pyroxene-rocks are found.

The schists fall into two groups, the coarse linear foliated actinolite-
schists, and the fine-grained, banded closely foliated glaucophane- and
muscovite-schists.

The actinolite-schists are green, coarse-grained rocks wholly built up
by large, fibrous crystals of green actinolite. The parallel arrangement of
the crystals, which occasionally attain a length of several cm., brings about
the linear structure of the rocks. Sometimes a varying amount of green
chlorites is found to replace the amphibole, ranging to almost pure massive
chlorite-schists.

Glaucophane- and muscovite-schists are not quite so common. They
are fine-grained and closely foliated and occur in irregular packets, which
always show evidence of strong tectonic disturbance in the close and irre-
gular folding of the different layers. The glaucophane-schists carry quartz
or quartz-clear albite in small irregular, sutured grains, and small needles of
glaucophane, with rigorous linear arrangement. The rocks are built up by
closely alternating darker and lighter zones, according to the abundance of

the amphibole-needles, which are completely lacking in some and pre-
dominant in other parts of the rocks. The muscovite-schists carry medium-
grained to fine-grained muscovite-leaves, together with chlorites and epidote,
or titanite as accessories.

The amphibolites, when fresh, are medium- to fine-grained white and
green rocks. Under the microscope they sometimes show linear, or parallel,
structure but this is never very distinct, so that it usually is not seen macros-
copically. Many of the rocks do not show any parallel arrangement of their
constituents whatever. They are built up by amphibole, with albite, zoisite,
epidote and muscovite in varying amounts. The amphiboles are light- to
dark-green, pleochroitic needles and prisms, with good cleavage, and
without a trace of the fibrous texture of the amphiboles in the urahtized
rocks. In some rocks we find a small amount of glaucophane together with
the green amphibole. The epidote and zoisite occur in small grains or larger
crystals, which then mostly take the form of short prisms. The albite is
formed in those places, where the texture of the rocks becomes coarser
and forms very large, allotriomorphic, untwinned absolutely clear poicilitic
crystals. The muscovite, which never plays an important part, is found in
small plates. The amounts of the diflFerent constituents vary widely. We
find rocks almost wholly built up by amphiboles and only accessory zoisite
or epidote ; rocks with amphibole and a considerable quantity of one of
these two, or of both of these minerals ; together with rocks where the
albite plays a very important part. These last may locally vary into rocks,
that are almost exclusively built up by clear, untwinned, albite with here
and there some needles of green amphibole.

We found several rocks carrying garnet, some massive and some with
schistous structure. Their mineral constituents place them with the eclo-
gites. Apart from the idiomorphic crystals of garnet decomposing into
chlorite and quartz, small always allotriomorphic crystals of a green pyroxene,
larger more or less idiomorphic prisms of green or blue amphibole, and
muscovite in small tables or leafs are found. Titanite and ore form acces-
sories, but in one rock the titanite was found in large quantities, occurring
in large idiomorphic crystals, attaining 4 X 1,5 mm.

General; Age: Rocks of dioritic parentage are found outcropping
in the TufF Series and in the Serpentines. In cuts along the Carretera Central
between Placetas and Falcon we can easily observe the true intrusive nature
of these rocks, which occur in small dikes. Elsewhere the exposures are
not good enough to yield direct results as to the age of the dioritic rocks
and the surrounding Tuffs or Serpentines. We may, however, consider the
silicification of diaÎDases and spilites from the Tuff Series, which nearly
always accompanies the dioritic rocks when found within the TufF Series,
as a contact metamorphism, due to the intrusion of the Dioritic rocks.

These thus are younger than the Tuffs and the Serpentines, and, ongt; the
other hand, older than the transgressive Habana Formation of Maastrichtian
age, which contains pebbles of dioritic rocks. The dioritic intrusions took
place between the intrusion of the peridotites and the sedimentation of the
Habana Formation, and are of Upper Cretaceous age.

We find diorites, quartz diorites, diorite-porphyrites and porphyrites,
also plagiaplites, albitites and malchites. The diorites are found within the
larger intrusions, along the Carretera Central between La Esperanza and
Santa Clara, Southwest of Santa Clara (A. 391—399), between Guaracabulla
and Falcon and Guaracabulla and Placetas, to the South of the Serpentine-
ridge, at M. 407 and V. 212, and in the neighbourhood of San Andres.
The diorite-porphyrites and the leucocratic and melanocratic rocks from
the many small dikes, are found throughout the area covered by the Tuff
Series and the Serpentines, whereas they also occur within the larger in-
. trusions mentioned.

Most rocks have a cataclastic structure, which varies in intensity and
is sometimes predominating. We find broken phenocrysts of felspar and
quartz with bent or twisted columns and leaves of amphibole and biotite,
or even whole shearing-zones, where all larger crystals have been ground
to small pieces. Just as the Serpentines, the dioritic rocks must have under-
gone considerable tectonic stresses.

Diorites s. s. The diorites and quartz-diorites are medium- to coarse-
grained, white-green rocks that are chiefly built up by plagioclases, with
quartz and amphibole and sometimes biotite or pyroxene. The amphibole
is idiomorphic, in prisms, light-green to greenish-brown pleochroitic. It
sometimes decomposes locally into green fibrous uralite. The plagioclase,
in more or less idiomorphic crystals, often with lamellar twinning or zonal
structure, when fresh, has the composition of labradorite, and is clear.
Sometimes we find cloudy crystals, with a composition ranging from
albite-oligoclase to oligoclase, and in several cases within these acid cloudy
crystals, a clear calcic core is found, denouncing the cloudy crystals to be
decalcified clear ones. The. quartz is found in large clear allotriomorphic
crystals. Sometimes we find a close intergrowth of quartz and plagioclase,
and the rock becomes a diorite-pegmatite. By their outstanding character,
the diorite-pegmatites, when found as pebbles in the younger formations,
are the easiest indicators that these formations are transgressive over the
Diorites.

Brown biotite sometimes is found in small leaves, and colourless augite
in short prisms. Apatite, titanite and magnetite are accessories.

Diorite-porphyrites. The diorite-porphyrites have the same mineral
constituents as the diorites, and differ only by their holocrystalline porphy-
ritic texture. Quartz may or may not occur as phenocrysts, distinguishing
between quartz-diorite-porphyrites and diorite-porphyrites.

Leucocratic dike-rocks: The leucocratic dikes, formed by albitites
and plagiaplites, are small-grained to dense white or light-green rocks,

with a hypidiomorphic or indistinct porphyritic texture. They are formed
by heavily clouded acid plagioclases, short, sometimes twinned, laths and
tables, with a composition varying from albite to oligoclase-andesine, and
by allotriomorphic clear quartz. Sometimes we find several green needles
of amphibole, whilst apatite, titanitc and sometimes a very small amount
of magnetite are accessories.

Melanocratic dike-rocks: The melanocratic dikes are formed by
malchites, very fine-grained white-and-green or dark-green rocks. They are
formed by plagioclase and amphibole in about equal quantities, with pan-
allotriomorphic granular texture, and with a small amount of quartz. The
plagioclase is clear, twinned labradorite or labradorite-bytownite. .The
amphibole is coloured green or brown, with small pleochroism. Magnetite
in small crystals is always present. Moreover, one dike of spessartite has
been found.

Contact metamorphism: With the larger Diorite intrusions through
the Tuff Series we often find traces of contact metamorphism. We probably
should have found more direct evidence, had it not been that the Diorites
and the rocks from the Tuff Series usually were rather weathered, and the
contact between the two formations not exposed. The spilites and diabases
from the Tuff Series near the contact are silicified to a certain extent. Between
the laths of the felspars, where in fresh rocks we find the grains of augite
that often are seen to urahtize or chloritize, are found irregular clear grains
of secondary quartz, that are grown together with other secondary minerals,
e. g. chlorite, epidote and uralite, thereby proving their secondary nature.
In several of the normal spilites and diabases with a strong decomposition
of the pyroxenes and a consequent large amount of secondary minerals
we also find some quartz and it looks as if this process — the decom-
position mainly of the chlorite to quartz — has been accelerated by the
nearby intrusions of the Diorites.

This phenomenon was typically observed in rocks of the Tuff Series
close to the Diorite intrusions between Guaracabulla and Falcon (M. 402—
M. 407 and M. 416), between Guaracabulla and Placeras (Near V. 215)
and South of General Carillo (A. 501), in the eastern part of the district.

General: Palmer (9) was the first writer on the geology of Cuba,
who gave a good account of this formation, as it outcrops in the vicinity
of the town of Habana. Although the pétrographie characters in the district
under discussion are distinct from those found near Habana — in fact there
is strong variation within the district itself —, its age and fossil content
is the same. I.ayers of this age, but varying locally in pétrographie and
lithologie character, are found at many places in Cuba and it is thought
best to give them all the same formational name, whilst the different, some-
times intergrading characters are described separately for each locality.

Age: The age of the Habana Formation is Uppermost Cretaceous, as
it can be parallelized with the Maastrichtian of Europe by the occurrence
of Larger Foraminifera of the genera Lepidorbifoides and Omphalocyclus.

It is transgressive over the Diorites and Tuff Series and their equivalent,
the Aptychi Limestones. Pebbles of diorite-porphyrite and quartz-diorite-
pegmatite are found, together with Vaughanina cubensis and fragments of
Rudists, at H. 482 and at L. 617, East and West of Falcon ; whilst pebbles
from the Tuff Series and the Aptychi Limestones are found at different
localities. In the southwestern part the structural discordance is clearly
indicated on the map, where we see the layers of the Habana Formation
transgressive over various older formations. For instance near Falcon over
Tuff Series, Aptychi Limestones and Serpentines ; and along the northern
limit of the Bernia-syncline over Tuff Series and Serpentines.

Just as with the Tuff Series and the Aptychi Limestones, we find a
strong difference of facies in the Habana Formation, between the northern
and the southern part of the district; the line of larger Serpentine-bodies
roughly indicating the boundary-line. Together with this change in facies
we find an intensified tectonic structure, when passing from South to North.

Southern facies: Typical for the Habana Formation in the southern
part of the district is the great syncline of Bernia to the South and Southwest
of the town of Santa Clara, and the exposures to the Northeast of this town
along the road to Remedios in the neighbourhood of Capiro. We find here
light-green glass-tuffs, crystal-tuffs, tuffaceous limestones, Rudist- and
Orbitoidal-limestones. The different layers vary strongly parallel to the
strike and are only found over short distances, when they taper out, to be
replaced by others, in an irregular way. The whole lithology, the rapid
thinning out of layers, the angular crystal-fragments in the tuffs and the
tuffaceous limestones, together with the local abundance of Rudists and
Orbitoids, is evidence of a littoral sedimentation. Although we find abundant
evidence of volcanic activity during the sedimentation of the formation in
this part of the country, we only found igneous rocks at two localities,
A. 127 and H. 213, both between San Juan and Pastora, where porphyrites
outcrop.

Differences with the Tuff Series: In the field the formation is
easily recognised when it carries Rudists or Orbitoids, but those sections
where glass-tuffs, tuffs and tuffaceous limestones are found, resemble to a
certain extent the layers of the older Tuff Series. The glass-tuffs from the
Habana differ, however, from those of the Tuff Series by their light-green
or whitish colour, which is much lighter than the usual colour of the older
glass-tuffs and tuffs. Moreover as a rule they have a much smaller specific
weight and a fresher appearance. Moreover in most cases smaller and larger
intercalations of limestones occur not unfrequently. These limestones con-
trast by their white or yellowish-brown colour with the grey or blue-grey
limestones, sometimes found intercalated within the Tuff Series, and can

also be distinguished by their coarser texture, which usually is granular
and may be finely conglomeratic or brecciaceous.

Under the microscope we find dense light-green glass-tuffs, which
only consist of clouded glass, and that are di fficult to distinguish from those
of the Tuff Series. But the coarser glass-tuffs and the tuffaceous limestones,
that vary from limestones with volcanic material towards tuffites with
calcareous cement, can be recognised by a number of features. They carry
fragments of porphyrites whose texture varies from hyalopilitic to holo-
crystalline, fragments of phenocrysts of plagioclase, quartz, sometimes of
augite, and crystals of magnetite. The plagioclases are always clear, with
lammellar twinning or zonal structure and are rather basic, with a compo-
sition of labradorite. They contrast with the plagioclase-fragments of the

tuffs from the Tuff Series by their clearness, twinning, zonal structure and
basic composition. These features are also sometimes found with older
tuffs, but always with the tuffs from the Habana Formation. Moreover the
almost constant occurrence of fragments of clear quartz-crystals is a dis-
tinguishing feature, as we almost always find quartz in the tuffs of the
Habana Formation, and never in tuffs from the older formations. In the
tuffaceous limestones, moreover, we often find fragments of Orbitoids, or
of Vaughanina cubensis, which at once determine the age of the rocks under
question, and lastly in this part of the island Radiolaria are rarely met
with in the Habana Formation. This characteristic does not hold good,
however, for the whole island, as Palmer (8) describes abundant radio-
larian deposits from this formation in other parts of the island, and there-
fore it should only be used in combination with the other characteristics
mentioned.

Intrusions of Porphyrites: The porphyrites found are dark-brown
and black, dense rocks. They carry phenocrysts of plagioclase and augite.
The plagioclase occurs in large tabular crystals with lammellar twinning
or zonal structure, mostly clear, sometimes slightly cloudy, that vary in
composition from andesine-labradorite to labradorite-bytownite. The augite
is colourless, and the crystals have the form of short prisms. Magnetite,
in smaller and larger crystals, is present. The fine-grained, partly vitre-
ous groundmass contains basic plagioclases, with some pyroxene and
magnetite.

Petrography: As we have seen, one of the differences between the
volcanic elements of the tuffs from the Flabana Formation and those of the
Tuff Series, is the occurrence in the Habana, of a considerable amount of
primary quartz. The parentage of the effusives thus is more dioritic than
gabbroid. In agreement with this fact, the chemical composition of a glasstuff
from the Habana Formation is that of a granite. (Analysis 17). The intrusive
augite-porphyrites seem to have a more gabbroid parentage by their mineral
constituents, but the chemical analysis of one of them also reveals a close
resemblance to a granitic magma (Analysis 16). When we take into consi-
deration the intrusions of Diorites and dioritic rocks into the older forma-
tions, it is highly probable that the volcanic activity that furnished the
material for the tuffs of the Habana Formation, and for the porphyrite-
intrusions in the Habana Formation, was allied to the igneous activity which
led to the intrusions of the dioritic rocks. We may consider the volcanic
activity, during the sedimentation of the Habana Formation, as the waning
of the igneous activity that formed the earlier Diorite intrusions.

Northern Facies: The difference in facies in the Habana Formation
between the northern and southern part of the district, is parallel to that
found between the Tuff Series and Aptychi Limestones. We see a conside-
rable decrease in volcanic matter, which in the northern facies of the Habana
Formation is almost non-existent. There are also indications that part of
the formation was sedimentated in a somewhat deeper sea. Whereas in the

South and Southwest, we found a perfect littoral lithology, in tlie northern
facies we find only scarce layers with Rudists or Orbitoids, These, together
with the coarsely brecciaceous elements indicate littoral sedimentation too.
Over large distances, however, dense, non-brecciated limestones, sometimes
with many Smaller Foraminifera, are evidence of uniform conditions of
sedimentation, and it is probable that this sedimentation took place in a
somewhat deeper sea.

The northern facies of the Habana Formation is characterised by white
and yellow brecciaceous limestones, white and yellow dense limestones,
and white or greyish finely conglomeraticaJ limestones. Sometimes we
find breccias of Rudists, or fragments of Orbitoids, by which the lime-
stones can be determined, but mostly they are sterile or the Smaller
Foraminifera can not be prepared out of the rocks for determination. The
coarse limestone-breccias and the dense yellowish limestones can be sepa-
rated, without fossils, from the older Aptychi Limestones, on their pétro-
graphie characters, but with the finely conglomeratic or brecciaceous
limestones, it is difficult to say whether rocks belong to the Habana or to
the Aptychi Formations ; and often only the finding of Orbitoids or Radio-
laria can decide the question. It is therefore possible, and even probable,
that in the northern ridges of Aptychi Limestones, beds of limestones of
the Habana Formation are folded and faulted together with the Aptychi
limestones. As we can not say anything definite on the structure of the
Aptychi Limestone-ridges, more detailed work may show them to contain
smaller or larger synclines of Habana Limestones alternating with anticlines
of Aptychi Limestones.

In the northern part, owing to the stronger influence of the post-
cretaceous orogenesis, the structural discordance between the Habana
Formation and the older beds is not so apparent from the map, as it is in
the South. At several localities we found, however, pebbles of rocks from
the Tuff Series or the Aptychi Limestones, as evidences of a structural
discordance between these two formations and the transgressive Habana
Formation. We found pebbles of Aptychi Limestones at L. 451, between
Placeras and Remedios ; pebbles of porphyrites, tuffs and Aptychi Limestones
at A. 369, between Placetas and Camajuani ; and lastly pebbles of radiolarian
cherts and glass-tuffs at L. 501, West of San Antonio.

General: We find the Upper Eocene over a large part of the south-
western portion of the district, and again in the north- and north-eastern
part. As with the older formations, the facies in the two regions is different,
as is the tectonic structure, and a separate discussion is desirable.

The age of the formatipn is established beyond doubt, by the occurrence
of Larger, and some Arenaceous Foraminifera of the genera Camerina,
Lepidocyclina, Helicolepidina, Discocyclina and Dictjoconus.

Southwestern facies: In the southwestern region we find for^ the
greater part white marls and limestones, often sterile, sometimes with
Smaller Foraminifera, that could not be prepared out. The northern boundary
of this territory is formed by a range of limestone-hills which begins to
the North of La Esperanza, near Coneydo, and passes with an approximate
northwestern strike South of San Diego del Valle. It is here transgressive
over Serpentines and Tuff Series and locally carries abundant pebbles from
these formations and from the Aptychi Limestones. Near Santa Isabel and
Jicotea we also find conglomeratical limestones and marls, with many
well-rounded, small pebbles of the older formations. The structures formed
hereabout are gentle, the dipping of the beds is low. Although we have
not found pebbles from the Habana Formation in sediments of the Upper
Eocene, the stratigraphie unconformity is apparent by the lack of fossils
from older divisions of the Eocene. The structural discordance between
Habana and Upper Eocene is clearly seen between San Juan and La Espe-
ranza ; where the gently folded Upper Eocene transgresses across the
synclinal of Bernia.

North of La Esperanza a tongue of Upper Eocene stretches eastward,
transgressing over various older formations, to well East of Santa Clara
town. We are here between the larger massifs of Serpentines, where, in
earlier times, strong tectonic disturbances have taken place, contrasting with
the more gentle structures formed in the southwestern region of the district.
This difference also holds true for the post-Eocene orogenesis, as the beds
from La Esperanza eastward, have been folded more heavily than those
to the West of La Esperanza. East of Santa Clara near the end of the trans-
gression of the Upper Eocene over Tuff Series and Serpentines, we observe
a number of alternating synclines and anticlines, locally with very steep dips.
Just as to the northwest of Conyedo, the Upper Eocene has here a basal
conglomerate with smaller and larger pebbles, mainly from the Tuff Series
and the Aptychi Limestones.

Here we also find several tuffaceous limestones, indicating a low vol-
canic activity in Upper Eocene times. This activity was low, compared to
that during the Habana period, as the tuffaceous limestones are much rarer
in the Eocene than in the Upper Cretaceous. Moreover the amount of
volcanic matter in the limestones is smaller in the younger sediments,
whereas the crystal-fragments often are somewhat rounded off; and we
never find true crystal-tuffs, practically without calcareous matter, as is the
case in the Habana Formation. The volcanic matter present is, however,
of quite the same habit — basic clear plagioclases, quartz and occasional
pyroxenes and fragments of porphyrites —, so that the tuffaceous limestones
from the Upper Eocene can only be distinguished from those of the Habana
Formation by their fossil content. Fragments of Discocyclind commonly
occur within the Upper Flocene limestones, so usually this presents no
serious difficulties.

Fauna: The fauna of the Upper Eocene in this region consists for a
great part of Larger Foraminifera, with some corals. Locally we find abun-
dant specimens of species of the genera Camerina, LepidocycUna and Discocy-
clina. This contrasts with the fauna of the northern facies, where we find
abundant Smaller Foraminijera of Rotalid parentage, with specimens of the
genus Dictyoconus. Specimens of the genus Discocyclina are the only Larger
Foraminifera found here, and they are rare, compared with the numbers
found in the southern facies.

Northern facies: The northern facies of the Upper Eocene for the
greater part comprises limestones. We find white and grey dense limestones,
but also many well bedded, fine-grained conglomeratical or oolithical^
white or greyish-brown limestones, that locally vary into brown calcareous
sandstones. These alternate with grey or light-green marly limestones. The
dense and fine-grained limestones often carry abundant Smaller Foraminifera
and also many specimens of Dictyoconus and fragments of Discocyclina.
The texture of these rocks distinguishes them in the field from thequot; dense
or brecciaceous, non- or badly bedded limestones of the Habana Formation.
The marly limestones of Upper Eocene age, in contrast to the beds of the
Habana Formation, locally carry abundant Radiolaria.

The Upper Eocene Formation in this region has been subject to a
strong post-Eocene orogenesis, as can be seen from the strong folding,
which has resulted in steep, sometimes vertical dips of the beds, and. West
of San Antonio de las Vueltas, we even find synclines of monoclinal build.

Although — probably through these effects of the post-Eocene oro-
genesis — the structural discordance between Upper Eocene and Habana
Formation is not apparent in the northern region of the district, we find
the same stratigraphical gap between Maastrichtian and Upper Eocene as
we found in the Southwest ; so we may assume that an unconformity between
these two formations exists over the whole district.

Beds of Oligocene age were only found at two localities in the south-
western part of the district, where they overly conformably the beds of
Upper Eocene age and are folded in gentle structures, with low dips. We
find white sterile marls, or marly limestones and yellowish-brown orbitoidal
limestones, sometimes with small pebbles from the older formations. In
pétrographie character and tectonical structure these beds thus are not to
be distinguished from the underlying beds of Upper Eocene age. We may
separate them by their fossil content only. In the two localities mentioned
typical Orbitoids of the subgenera Nephrolepidina and Eulepidina were found.
The tectonic concordance of Oligocene and Upper Eocene proves that the
post-Eocene orogenesis— which in the southwestern part of the district
was rather weak, but grew in intensity towards the North and FLast —,
took place during younger Oligocene times.

Palmer (9) gives a full discussion of these limestones of Oligo-Miocene
age, characterised by unfolded horizontal beds of white or brownish lime-
stones, with a very singular, cavernous, habit, caused by the weathering
out of abundant Gastropoda and other fossils. Their moulds and casts can
be recognised everywhere, without, however, permitting a specific deter-
mination of the fossils after which they were formed. We only found it
South of Quemado de Guines, whilst perhaps the horizontal limestones
with jagged surface, found between Sagua la Grande and the coast at
La Isabella, belong to the same formation. Palmer gives the jagged surface,
which in extreme cases forms the 'Dientes de Perro', as a distinguishing
feature of the limestones of this formation. We did, however, repeatedly
find the same 'Dientes de Perro' structure with the massive limestones from
the Habana Formation, South and West of Remedios.

Orogenetic phases: Tliree different phases of orogenesis can be
distinguished in this part of the island, namely the first one during the
Upper Cretaceous, before the sedimentation of the Habana Formation in
Maastrichtian time; the second during the Middle or Lower Eocene; and
the third after the sedimentation of the Upper Eocene and Oligocene sedi-
ments. These have all caused a folding, and sometimes faulting, of the beds
affected. Since the last orogenetic phase during the Oligocene no horizontal
movements have taken place, as is evidenced by the horizontal beds of the
Guines Limestone, and we find evidence only of a vertical uplifting of the
Guines Limestones over large areas.

The first, pre-Maastrichtian, orogenesis was comparatively gentle and
we find no great discordances between the Habana Formation and the
underlying Tuff Series or Serpentines. It is proved by the occurrence of
pebbles of rocks from the Diorite intrusions, and from the Tuff Series, in
layers of the Habana Formation and by the overlap of the Habana Formation
over the older layers. We see this last feature very clearly Southw^est of
Santa Clara, where Habana overlies Serpentines near La Esperanza and
Tuff Series more to the Southeast, near Bernia ; and also West of Falcon.
During this orogenesis the intrusion took place of the large amounts of
peridotites and the somewhat younger diorites.

During the two following phases of orogenesis the structures formed
by the first phase were accentuated, and the large overthrusts, together
with the monoclinal build of the interjacent wedges, — producing an
imbricate structure of the whole country northward from the Serpentine-
massifs — were formed. We can not now distinguish between the share
each one of the two last phases had in the forming of this structure, as
sediments of Upper Eocene age are wanting over the larger part of'the
heavily folded country.

Difference between northern and southern part. The sections
given, clearly indicate the difference in tectonical structure between the
southern and the northern part of the district. In the syncline of Bernia
we find even gently folded layers and a large, comparatively smooth struc-
ture. This is even more the case to the West of the syncline of Bernia, where
the transgressive Upper Eocene sediments form gently undulating structures,
with low-dipping beds. Contrasting herewith are the narrow wedges with
steep dips, bounded by overthrusts, and the Upper Eocene synclines of
monoclinal build, found in the northern and eastern part.

This difFerence in tectonic structure can not be explained by the facies-
differences between the northern and southern parts only, for these facies-
differences are gradual, and we find layers of southern facies intercalated
within those of northern facies and vice versa. We can only explain it by
a general growth of tectonic, activity towards the North and East. The
facies-difference between the Tuff Series and the Aptychi Limestones of
Lower Cretaceous age, which difference is parallel to that found in younger
layers, indicates that the difference between northern and southern part,
existed already in Lower Cretaceous times, and survived throughout the
three different orogenetic phases.

Thickness of formations: As will be noted I have not stated the
thickness of the different formations. This is omitted for various reasons.
The Tuff Series, along the southern boundary of the district, only shows
the northern end of a large area as it outcrops also to the South of the
district so that the thickness of this series can not, at present, be given.

The Aptychi Limestones are found only in narrow wedges with pre-
vailing monochnal build and bounded by overthrusts. The absence of index
horizons in these limestones makes it impossible to observe a repetition of
layers, which might well occur together with the imbricate structure found ;
whilst on the other hand, the overthrusts at the contacts may conceal large
parts of the formation. By the first feature one would be inclined to give
an exaggerated idea of the thickness of the hmestones, the second feature
produces a contrary result. As we know nothing about the relative impor-
tance of these two features, we can only guess as to the thickness of the
Aptychi Limestones. The sections given illustrate the geographical extent
covered by beds of this formation, and give an idea of the rougher dimen-
sions of its vertical extent.

The Habana Formation and younger sediments in the southwestern
part are transgressive, with a variable Hthology and thickness. This is
illustrated by the section I, through the syncline of Bernia, where the
Habana Formation is much thicker in the southern flank of the synchne
than it is in its northern flank. This can be explained by a wedging out
of the layers towards the Northeast. The younger formations elsewhere on
the island — in the structural basins — attain a considerable thickness
(Palmer, Bibl. 9), whilst they are found in this district only as a thin cover.
Computed values given for their thickness in this part of the island thus
are not representative for these formations.

In the northeastern part of the district the Habana and Upper Eocene
Formations do not exhibit such a variable lithology, but here they are
strongly folded, with overthrusts formed in several places at the contacts
between Aptychi Limestones and Habana Formation, so that here also a
computation of the formation's thicknesses remains very uncertain.

From a number of Cuban rocks Mr. W. van Tongeren of Utrecht
kindly made chemical analyses, so that the chemical properties of the rocks
from the different formations can be discussed. The analyses are given
below, together with seven analyses from other Cuban rocks, given by
Schurmann (Bibl. 12), that were also executed by Mr. van Tongeren.

The NiGGLi-values were computed, and a differentiation-diagram was
drawn. Niggli (Bibl. 7) gives yet another method by which the quantities
of normative minerals in molecular proportions can be easily drawn in a
triangular projection. From the three angles of a triangle we put down
the quotient of the normative molecular amount of free silica with the
total molecular amount of silica, Qs, secondly the quotient of the normative
molecular amount of silica used by the molecular normative leucocratic
components and the total amount of silica, Ls, thirdly the quotient of the
molecular amount of silica used by the molecular normative melanocratic
components with the total molecular amount of silica, Fs. The sum of Qs,
Ls and Fs is always the unit, and therefore we may use the triangular pro-
jection. Ls and Fs are computed with the supposition that molecules with
the highest grade of silicification are formed. If this is really not the case,
we find this expressed by a negative Qs. Together with the projections of
the Cuban rocks the mean values of several types of rocks, according to
Niggli, are put down.

From the differentiation-diagram we see that the Cuban rocks belong
to the common alkali-calc series, giving a normal differentiation diagram.

From the triangular projection we see that the rocks from the Tuff
Series, analyses 10 and 8, lie between the mean values for gabbro and for
syenite, thus chemically confirming the facts we had already noted with
the pétrographie description of the spilites and diabases.

Number 11, Tuff-Series-diabase found as inclusion in the Serpentines
illustrates the close chemical parentage of these rocks with the volcanics
from the Tuff Series, a parentage we have already noted with the pétro-
graphie description of these inclusions from the Serpentines. Number 9,
a spilite from the Tuff Series, silicified by the intrusion of the Diorites,
truly has a much more acid character than the un-altered rocks of this
Series. The chemical parentage of the rocks from the Diorite intrusions
and the glass-tuffs (number 17) and porphyrites (number 16) from the
Habana Formation, is equally well illustrated in the triangular projection.
It will be seen that these rocks, with the exeption of number 15, a melano-
cratic, malchitic dike-rock, have about the chemical composition of a granite.

Yet petrogfaphically they have a true dioritic or quartz-dioritic parentage
as they never carry orthodase felspars but always plagioclase felspars'
with phenocrysts usually even of a rather basic composition. This is a
general feature of the Cuban rocks in so far as we find it also with the rocks
from the Tuff Series. These last mentioned rocks with their beautiful ophitic
structure, their considerable amount of pyroxene, and absence of biotite
or amphiboles, should have a gabbroid composition. Instead they are more
acid, and intermediate in composition between gabbros and syenites. Just
so with the rocks from the Diorite-intrusions, which petrographically are
to be classed with the diorites, and chemically with the granites. It is hoped
that examination of equivalent rocks from other parts of the island may
show, if this difference is accidental, or due to a regional Cuban or An-
tillean feature.

The composition of the numbers 12 and 13, foreign inclusions from
the Serpentines of the meso-metamorphic group, do not give any evidence
as to their origin.

The analyses No. 1—7 are those, given by Schurmann (12), Numbers
1—4 are of Dioritic rocks, numbers 5—7 are of rocks from the Serpentines.

Nr. 8 is a spihte, taken at V. 211, between Guaracabulla and Falcon.
Nr. 9 is a sihcified spihte, taken at M. 416, South of Falcon.
Nr. 10 is a diabase from the Tuff Series, taken at M. 374, near Santa Clarita.
Nr. 11 is a diabase, a foreign inclusion in the Serpentines, taken at M. 371,
near the former locality.

South from Encrucijada, at H. 502.
Nr. 13 is a glaucophane-eclogite, a foreign inclusion from the Serpentines,

taken along the Carretera Central, 11 km. East of Santa Clara.
Nr. 14 is a diorite, from the Diorite-intrusion Southwest of Santa Clara
at A. 395.

in the Serpentines, at M. 434, just South of Falcon.
Nr. 16 is an augite-porphyrite from the base of the Habana Formation

at H. 213, East of San Juan.
Nr. 17 is a glass-tuff from the Habana Formation, West of Santa Clara
at L. 359.

'/oo yvi?

Nepheh'ne

Most of the results of the work on the fossil remains, found in the
northern part of the province of Santa Clara, has been, or will be, published
elsewhere, to make it more accessible to purely paleontological workers.
These pubhcations will not be repeated here, and only faunal lists, with
find-spots of the different fossils, will be given.

The ammonite Aptychi of the formation bearing this name have been
specifically determined by Prof. F. Trauth, of Vienna (Bibl. 13).

The remains of Ammonites will be determined by Prof. E. Jawgrski
of Bonn. The results will be published later on, but Prof. Jawgrski kindly
permitted me to pubhsh here the provisional results, that are of geological
interest also.

The Larger Foraminijera of Maastrichtian, Upper Eocene and Oligocene
age have been specifically determined by me (Bibl. 11).

The Rudists and Rudistids from the Habana Formation have been
described by me in a paper, submitted for pubhcation to the Journal of
Paleontology.

L.362, L.363, L. 373, L.407, L.461, L. 467, L.471, L. 479, L. 525,
L.527, H. 198, H. 394, H.40I, H.406, H.410, H.545, H.548, V. 178,
y. JS2, V. 184, V. 186, V. 187, V. 193, V. 198, V, 203, F. 262, V. 313,
V.399,nbsp;A.U3, A. 363, A. 388, A. 422, M.327, M.381, M.382,

With the exception of L. 373, L.461, H.406, H. 410 and A. 143 ah
these localities are situated in the Tuff Series or the Aptychi Limestones.

The age of L. 373 Is not certain, the other four localities are of Upper
Eocene age.

Ammonites or Ammonite Aptychi were found at the following
localities: L.362, L. 535, L. 619, H. 487—489, M. 520, M. 604.

L. 362, H. 487—489 and M. 520 are situated in the northern ranges
of Aptychi Limestones and the determination of the Opercula by Prof. Trauth
indicates a Lowermost Cretaceous age for these limestones.

L. 535, L. 619 and M. 604 are limestones, intercalated in the TufF
Series in the southern half of the district. The provisional determination
of the Ammonites by Jawgrski yielded the following species :

Peroniceras ex. afF. tricarinatus (Fric.) Burckhardt 1919
Peroniceras indet. cf. c-:(örnigi Redtenbacher
Peroniceras sp. indet.

L. 535, L. 619.
L. 535.
M. 604.

L. 535, M. 604.
L. 535.
L. 535.
L. 619.
M. 604.

Barroisiceras sp. indet. Nr. 7 Burckhardt 1919
Crioceras sp. indet. Burckhardt 1919

The Pachjdiscus ex. aff. tricarinatus (Fric.) Burckhardt 1919, together
with the Crioceras sp, indet. Burckhardt 1919 and the Barroisiceras sp. indet.
Nr. 7 Burckhardt 1919 are ah described from the Peroniceras-Barroisiceras
beds of Zumpango del Rio in Mexico. These beds lie at the boundary
between the Turonian and the Emscherian, or belong to the Lower Em-
scherian. The Austiniceras dihleyi Spath is known from the Turonian of
England and Algiers and the Peroniceras cocchi Meneghini from the Lower
Senonian of Toscana. These determinations thus indicate an Turonian-
Emscherian age for the limestone-intercalations in the Tuff Series. The
oldest sediments of the TufF Series must be of Lowermost Cretaceous age,
by their interbedding in the northern half of the district with the Aptychi
Limestones, but the younger elements of the Tuff Series range up to the
boundary between the Middle and Upper Cretaceous.

Orhitoides sp.
Omphalocyclus sp.
Torreina torrei Palmer
Lepidorhitoides minima H. Douville
Lepidorbitoides planasi M. Rutten
Lepidorhitoides cubensis (Palmer)
Lepidorbitoides rooki Vaughan and Cole
Lepidorhitoides aguayot Palmer
Lepidorbitoides sp.
Lepidorbitoides (Lepidorbitoides) sp.
Pseudorbitoides trechmanni H. Douville

Fossils :

Torreites sanche-:(i (H. Douville)
Barrettia monilifera Woodward
Barrettia multilirata Whitfield
Par as trom a sp.

Biradiolites cf. lameracensis Toucas
Biradiolites cubensis H. Douvillé
Bournonia sp.

Parabournonia hispida H. Douvillé
Chiapasella cubensis M. Rutten
Plagioptjchus antillarum (H. Douvillé)
Nerinea cf. bicincta Bronn

Dictyoconus fontabellensis (Vaughan)
Camerina macgillavryi M. Rutten
Ca??ierina malbertii M. Rutten
Camerina petri M. Rutten

LepidocycUna r-douvillei Lisson
LepidocycUna georgiana Cushman
LepidocycUna meim^eri Vaughan
LepidocycUna supera (Conrad)
LepidocycUna piedrasensis Vaughan
LepidocycUna semmesi Vaughan and Cole
LepidocycUna sp.
Helicolepidina spiralis Tobler

L. 158, FL 63, H. 66.
L. 158, H. 61, H. 63, H. 66,
H. 374, H.-381.
L.390, L. 393, V.328.

H. 374, H. 381, FL 384.
L.390, H. 61, H. 63, FL 66.
H. 374, H. 392.
L.393.
L.507.

L. 158, H.66.
H. 66, H. 374.
H. 66, H. 374, H. 392.
H. 66, H.374, H.392.
L.158, L.388, H.61.
H. 66, H. 374.

List of fossils from the Upper Eocene.

Localities :

Lepidocyclina piedrasensis Vaughannbsp;L, 156, I.. 157, H. 80.
Lepidocyclina tournoueri Lemoine and

Cushmania fontabellensis, Vaughan, 1928, Jour, of Pal., Vol. 1, no. 4, p. 282, pi. 44, fig. 3.
Dictyoconus fontabellensis, Vaughan, 1932, Jour, of Pal., Vol. 6, no. 1, pp. 97, 98, pi. 14, fig. 6, 7.

Small forms, with outer characters varying. In most cases the diameter
of the basis is larger than the height, but sometimes they are equal. They
are characterised by a rather coarse structure, the platforms are set wide
apart; near the centre of the basis the distance between two platforms
varies from 0,10 mm. to 0,15 mm.

Vaughanina cubensis, Palmer, D. K., Soc. Cubana de Hist. Nat., Mem., Vol. 8, no. 4, pp. 240_243

x\s may be seen from the number of find-spots of this fossil, which
is larger than that of any other fossil from the Habana formation, this
species is widely distributed in Upper Cretaceous Cuban layers, where it
serves as an excellent index fossil.

OrbitolHes (Orbiloides) supera, Conrad, 1865, Acad. Nat. Sci., Philadelphia, Proc., no. 2, p. 74.
Lepidocyclina [Lepidocyclina) supera, Douvillé, H., 1924, Mém. Soc. Geol. France, n. S., T. i., Mém. 2,

p. 40, figs. 23—26, pi. 1, figs. 9, 10.
Lepidocyclina [Lepidocyclina) mortoni, Rutten, M., 1935, Journ. o. Pal., Vol. 9, no. 6, pp. 538, 539.

When I studied the Larger Foraminifera of the district I concluded
from illustrations of Cushmans species Lepidocyclina mortoni (Bibl. 1, pi. 27,
figs. 1—4, pi. 28, figs. 1, 2.) that this species had hexagonal equatorial
chambers, arranged on concentric circles, and identified specimens from
Cuban material with this species, at the same time drawing attention to
the resemblance of L. mortoni and L. supera. The same view was held by
van de Geyn amp; van der Vlerk, (3), who placed L. mortoni under the
synonymy of L. supera. However, the extensive redescription of L. ?}jortoni
from the type-locality by Gravell amp; Hanna (4.), shows this species to
be characterised by rhomboid equatorial chambers, arranged on intersecting,
outwardly convex curves. The Cuban specimens, flat discoidal forms, with
hexagonal equatorial chambers, arranged on concentric circles, with only

Fig. 6. Diplochaetetes longitubus, horizontal section, X 30. Partly sectioned
floors at a, irregular cavities at b.

Fig. 8. Diplochaetetes longitubus, vertical section, Illustrating the irregular position of the floors, x 30.

a few layers of low lateral chambers, must now be identified with Lepido-
cyclina supera (Conrad), which thus also occurs in Upper Eocene layers, and
is specifically distinct from Lepidocyclina mortoni Cushman.

Upper Eocene, Santa Clara Province, Cuba. Hypotypes, Min.-Geol.
Inst., Utrecht, D. 14035—14044.

Monliculaslrea regularis. Kühn, 1933, Palaeontographica, bd. LXXIX, A, 1. 3—6, p. 195, taf. XVIIl,
fig. 12, taf. XIX, fig. 1.

The small, rounded hills between the rows of calices are flat. The
valleys with the columella have sharp edges and form rather regular hexagons.
The diameter of these varies from 5 mm. to 8 mm., with a mean value
of 7 mm. As in the type-specimen there are 7 to 10 septa for every 5 mm.
length of columella.

Upper Eocene, Santa Clara Province, Cuba. Hypotypes, Min.-Geol.
Inst., Utrecht, Coll., Pa. 1935, 302 ; D. 14431, 14432.

Diplochaetetes longitubus, Weissermel, 1913, Geol. Erforsch. Deutsch. Schutzg. Beilr., heft5, pp.84—108,

textfig. 1, 2, pi. 13, figs. 1—3.---, Weissermel, 1926, in Kaiser, Diamantenwuste Siid-

westafrikas, Berlin, bd. ii, pp. 88, 89, pi. figs. 1, 2, textpl. c, figs. 1—3.

The Structure of these striking corals is absolutely identical with that
given by Weissermel, so that there is no doubt that the forms are specifi-
cally identical.

Walls double, septa wanting, horizontal diameter of calices varying
between 1 mm. and 2 mm. with a mean value of 1,5 mm., floors scarce
and irregularly placed. The corals grow by the division of tubes; when
the space available augments. They are much smaller than those from the
type-locality. One well preserved specimen has a height of 2 cm. It is
flat-oval in outline, the largest horizontal diameters being 4 cm. x 5,5 cm.
and it is attached to the lower tip of the colony.

Upper Eocene, Santa Clara Province, Cuba. Hypotypes, Min.-Geol.
Inst., Coll., Pa. 1935, 301 ; Cb. 1933, 116; D. 14428—14430.

^mnea hicincla, Bronn, 1836, Ncues Jahrb. f. Min. etc., p. 562, t. 6, fig. 14,---, Goldfuss, 1844,

Broken specimens embedded in hard limestone rock and only to be
studied in sections. Horizontal diameter at the upper side varies from
about 3 cm. to 6 cm. The sections through the coils reveal the simple
infoldings, typical of the genus. There are three central folds, one of which
is placed at the upper side of the spiral; and one lateral fold.

Maastrichtian, Santa Clara Province Cuba. Hypotypes, Min.-Geol. Inst.,
Utrecht. Coll. Cb. 1933, 51—53.

I'igs. 9, 10. Nerinea cf. bicincta. Locality H. 550, between La Esperanza and Santa Clara.
9. Oblique section through young specimen. X Vi-
10. Vertical section through three consecutive windings of a large specimen, x Vi-

The importance of northern Santa Clara from an economic viewpoint
is very small. With the Serpentines occur small bodies of iron- or chromium-
ore which sometimes have been mined for a short time.

Locally the Diorites brought a small amount of^old. One abandoned
gold-mine, the Mina Isel, is situated on the path from Guaracabulla to
Falcon. After the conquest of the island by the Spaniards placer-gold was
found in the beds of the Rio Arimao and Rio Caonao, and this led to
prospecting work being done higher up in the basins of these rivers, and
also in the neighbourhood of Guaracabulla, without, however, yielding
much result.

In several localities seeps of asfalt are found, which is being mined
now at the mine Anna Maria, Southwest of Placetas. These findspots are
numerous near Santa Clarita, and here they are situated along the contact
between the Serpentines and the Aptychi Limestones. The Aptychi Lime-
stones are to a certain extent oil-bearing. We often find traces of oil along
the limestone-bedding-planes or the limestones give a definite odour, when
broken. We may explain the asfalt-seeps near Santa Clarita by the tectonical
contact between the Serpentines and the Aptychi Limestones. If the plane
of overthrusting between the two formations has a southern dip, imperforate
rocks from the Serpentines overlie steeply folded, pervious limestones. Oil
may accumulate against the overthrust-plane, and escape along the contact
of the two formations. The economic importance of these indications is,
however, practically nil, as the Aptychi Limestones are too heavily folded
to present useful structures and the contacts of Serpentines and Aptychi
Limestones in all probability do not offer enough space for the accumulation
of larger oil-masses.

The road leaves Santa Clara in the northeastern part of the town and
it is here still in the Serpentine district. Soon it passes into the Habana
Formation, where white brecciated or fine-grained limestones predominate
over light-green glasstuffs. At Capiro, the limestones are well exposed in
quarries to the North and South of the road (V. 157, 158). They are steeply
folded and small faults occur. Near the Granja Agricola the Habana For-
mation is overlaid by Upper Eocene, characterised by white marly limestones
and tuffaceous limestones, that form gently undulating structures. In the
Rio Ochoa we find a silicified spilitic rock (V. 162a), that is likely to belong
to the Tuff Formation, and over the river we pass into the Serpentines,
with veins of gabbro that show a strong uralitisation and a cataclastic
structure. The road then passes through the southern flank of a small hill,
the Bonachea, that is formed by steeply and irregularly folded grey and red
limestones and marls from the Aptychi Formation (V. 168), and again
comes into the Serpentines, until after the crossing of the Rio Sagua la
Chica and the railroad at Santa Fe. Before us we see here a ridge of hills
with a Northwest—Southeastern trend, the Loma Santa Fe. (See fig. 11,
p. 45). It is formed by limestones of the Aptychi Formation, that are steeply
folded and sometimes faulted, with strikes running roughly parallel to the
trend of the ridge (V. 178—186). Although the contact with the Serpentines
is sharply defined, no trace of metamorphism in the limestones is found.
We find here grey and bluishgrey limestones and marly limestones, with
layers and lenses of dark chert. Radiolaria are very abundant. Several layers
of tuffaceous limestone are encountered and in one place we find a brown,
fine-grained sandstone, built up by fragments of quartz and plagioclase
felspars, with some muscovite and calcite (V. 186). Owing to the strong
folding nothing definite of the tectonic structure of the ridge can be said.
In connection with the facts found at the path from Falcon to Camajuani,
we may assume that the Serpentines are brought into tectonical contact
with the Aptychi limestones by an overthrust.

On the eastern flank of the Loma Santa Fe are exposed greyish marls
and finely brecciaceous limestones, which, on microscopical examination,
are found to contain Orbitoids and belong to the Habana Formation (V. 188).
We then pass into a small zone of Serpentine that is very weathered, and
recognised by the more resistent foreign inclusions. Over the railroad we

Fig. 12. Detailed geologic map of part of the road
between Camajuani and Falcon. Scale 1 : 25.000.

s
«

pass into the Tuff Series, represented by glass-tuffs and prophyrite-tuffs
without stratification (V. 190—192). From V. 193 till we reach the village
of Camajuani, we once more cross a zone of grey limestones with inter-
calated dark cherts from the Aptychi Formation. Between Camajuani and
Remedios, we find white and grey brecciated limestones, that contain
Orbitoids of the Habana Formation near Camajuani, and fragments of
Rudists of the sub-family of the Radiolitinae at V. 244. Near Camajuani the
limestones are folded with a general strike of N. 120 E. and they dip towards
the Southwest. They must lie in tectonical contact with the older Aptychi
Limestones. Nearing Remedios nothing can be said about strike and dip
of the limestones, that are very cavernous and form 'Dientes de Perro'.

Between Remedios and Cailjairien the Upper Eocene crosses the road
in a low ridge with a strike of N. 115 E. It is represented by greyish brown,
solid or fine-grained limestones with many micro-fossils, mainly Smaller
Forammfera ; whilst also Dictyoconus and fragments of Discocyclina are found
(L. 458-460). In one place we find a marly limestone with abundant
Radiolaria. The limestones strike from N. 95 E. to N. 130 E. with a northerly
dip of 25-40 degrees.

From Santa Clara to Placetas we follow the new highroad, the Carretera
Central. It runs close to the northern boundary of the large Serpentine
district, which forms the hills of the Sierra Alta de Agabama to the South
of the Carretera. Near V. 399 the boundary between the Serpentines and
the transgressive younger formations crosses the road for a very small
stretch and white marls of the Upper Eocene are found. The Serpentines
contain many foreign inclusions, and also veins of normal and urahtised
gabbro. At A. 341 we are still in the Serpentine but A. 340 brings a medium-
grained cristallyne albitite, that is followed by weathered porphyrites of the
Tuff Formation (A. 338). Near L. 619 they pass with a small fault into grey,
well stratified limestones that carry remains of Ammonites. The determination
of the Ammonites places these sediments at the boundary between the
Turonian and the Emscherian, so they are much younger than the Aptychi
Limestones further to the North. They are strongly folded with a general
strike of N. 115 E.—N. 140 E. These strikes cut obliquely over the contact
of Tuffs and Limestones with the Serpentines, thus indicating that the
contact between the Serpentines and the older rocks is a tectonical one.

The railroad here crosses under the Carretera, and we pass into the
Habana Formation, which is exposed until we reach the valley of the Rio
Sagua la Chica near Falcon. It is characterised by white limestones and marls,
locally carrying abundant organisms, chiefly smaller Foraminifera of the
Glohigerina group. Vaughanina cubensis and fragments of Rudists occur.

The steeply folded limestones alternate with tuffaceous limestones and
breccias with fragments of porphyrites of the Tuff Series and also some

pebbles of dioritic rocks. On the eastern side of Falcon we find a large
quarry with white to light-green marly limestones, over a basal conglomerate
with many boulders from the older formations. We found here augite-
porphyrite, diabase and uralite-diabase from the Tuff Series, a uralite-rock
wWch most probably comes from the Serpentines, and a brecciated quartz-
dioriteporphyrite from the Diorites. The rocks gently dip towards the
Northeast and the patch of limestones is surrounded at all sides by the
alluvial plains of the Rio Sagua and its affluents. During our fieldwork we
parallehsed these rocks with those of the Habana Formation found to the
East and West. On microscopical examination however, some of the lime-
stone-boulders were found to contain Vaughanina cubensis, whilst the greenish
limestones contain abundantnbsp;If the rocks are of Maastrichtian age,

the limestone-boulders must have been formed during or immediately before
sedinientation. Moreover Radiolaria are very scarce in the Habana Formation
as it is exposed in Santa Clara. There remains the possibility that we have
here rocks of Eocene or Oligocene age, but without index fossils the question
can not be answered. As this patch of limestones is flanked by limestones
of the Habana Formation I have provisorily dated them as Habana also
Eastward of the limestone quarry we find alluvial plains and then
porphyrites of the Tuff Formation, which are replaced by steeply folded
tuffaceous limestones of the Habana Formation at L. 371. To the North of
the Carretera Central it is exposed as white limestones, with boulders of
porphyrite and quartzdiorite-pegmatite respectively of the Tuff Formation
and of the Diorites. Here it contains fragments of Rudists of the sub-family
of the Radiolitinae and characteristic Foraminifera, e. g. Orbitoides and
Vaughanina (H. 480, 482). At L. 369 we pass once more into the Serpentines
containing many dikes of diorite-porphyrite and gabbro. To the North'
the Habana formation runs parallel to the Carretera in a series of low hills'
It is found at M. 500 and at L. 364 it crosses the road for a short space'
to be replaced by greenish brown or white, well bedded glass-tuffs, radio-
larian tufTites and radiolarian cherts of the Tuff Formation (L. 362, 363) ;
with a small vein of a augite-spessartite near L. 362. They pass again into
the Serpentines at the next bend of the road. Strikes and dips of these beds
are in no connection whatever with the boundaries between the Serpentines
and the Tuff Formation, so these boundaries are formed by faults or over-
thrusts.

From Placetas northward we find Serpentines, until we reach the hills
that are the direct continuation of the Loma Santa Fé, and are formed by
steeply folded and faulted well bedded limestones with intercalated layers
and lenses of chert (L. 441—443). At the railroad crossing of San José
begins the Tuff Formation, with some veins of Dioritic rocks, e. g. a malchite
and a diorite.

South of Zulueta we once more cross a zone of steeply folded limestones
and cherts from the Aptychi Formation. At L. 447 the limestones are strongly
brecciated and in places have the same habit as breccia-limestones from the

Habana Formation. The components, however, are all derived from the
Aptychi Formation and comprise limestones, radiolarian limestones, and
cherts, and we may consider the breccia as a mylonitic one, formed on an
overthrust. This is in agreement with the fact that to the Southeast, in the
direction of the strike, we find a zone of Serpentine intercalated between
the Aptychi Limestones on the courses from Remate, General Carillo and
Jarahueca Southward. The Aptychi Limestones are found up to L. 451,
north of Zulueta, where they are replaced by white, oolithical or breccia-
ceous limestones from the Habana Formation with fragments of Radiolitinae
and Orbitoids. They have a Northwest—Southeast strike and a southern
dip and are thus brought into tectonical contact with the Aptychi Limestones
by an overthrust. Nearing Remedios the limestones have much the same
appearance as between Camajuani and Remedios. Nothing can be said
about their structure and no index fossils w^ere found.

East of Santa Clara the boundary between the trangressive Upper
Eocene and the Tuff Formation is rather well exposed. The Eocene forms
three synclines and the Tuffs are exposed in the corresponding anticlines.
(See Section IV). At V. 382 the Eocene rests on the Tuffs with a basal conglo-
merate with boulders of porphyrite, dioriteporphyrite, aptychi-limestones
and cherts. The Eocene comprises white marls and limestones, alternating
with tuffaceous limestones and calcareous sandstones, that grade into the
basal conglomerate. The tuffaceous limestones are very similar to those from
the Habana Formation, but under the microscope the foreign fragments
appear much more rounded, thus forming intermediate stages between
tuffites and sandstones. Discocyclina s.s. and Asterocyclina are found.

From La Movida to the Bonachea (H. 397—429) (See Section V)
we start at the Carretera Central with Serpentine, with dikes of Diorite,
followed almost directly by glass-tuffs and occasional radiolarian limestones
of the Tuff Formation. Here also we find a dike of plagiaplite at H. 403.
At H. 409 we pass a small zone of amphiboliteschists, typical inclusions of
the Serpentines and then find gently folded white and grey limestones
with Radiolaria, that can be connected with one of the Upper Eocene
synclines further to the West. At H. 411 begins a band of Serpentines,
with many foreign inclusions, e. g. chloriteschists, zoisite-amphibolites,
glaucophane-amphibolites. At H. 411 we find a practically unaltered
harzburgite. The Serpentines last till H. 424 where we cross the Aptychi
Limestones in the prolongation of the Bonachea. The contact between
the red and grey limestones and the Serpentines is very sharp, and we
find evidence that it is of a tectonical nature. Along the southern limit
the limestones are brecciated and contain sharp-edged broken fragments
of Serpentine (See fig. 1, p. 13), and on the northern flank the Serpentines
close to the contact, have a foliated structure with the strike of the foliation

running N. 155 E., that is to say, parallel to tlic contact of Serpentines and
Aptychi limestones (See pi. fig. 2). The Serpentines continue from here
till we reach the road from Santa Clara to Camajuani.

From La Movida to Santa Fe we first follow the railroad of the
Ferrocarril de Cuba, which passes the boundary between the Tuff Formation
and the Serpentines, and then we take a path to the North. At H. 535 we
find a sharp contact between the Aptychi Limestones and the Serpentines,
characterised, here also, by a breccia of limestone with fragments of
serpentine. North of the zone of Aptychi Limestones we find Serpentines,
till we reach Santa Fe, on the road from Santa Clara to Camajuani.

From Santa Fe to the Carretera Central, we pass through Ser-
pentines, till we cross the Rio Sagua la Chica at V. 262, where heavily
folded marls, limestones and radiolarian cherts of the Aptychi Formation
are exposed. These can be connected with a small ridge of Aptychi Lime-
stones, that leave the Loma Santa Fe to the East at M. 361, but do not
make a direct, fault-less connection with the Aptychi Limestones that come
from the Bonachea. South of this small band of hmestones we find white
and green glass-tuffs and tuffoid porphyrites. The glass-tuffs contain large
angular fragments of quartz which, together with their light colour, makes
it probable that they belong to the Habana Formation. I have connected
these rocks with true exposures of Habana along the Carretera Central
(A. 331—^336) and near Santa Clarita (M. 385 and 381). So we get a large
patch of transgressive Cretaceous, which more or less corresponds with
the plains of the Rio Sagua la Chica. To draw the real extent of this patch,
the scanty data available are insufficient. Before crossing the railroad we
come again into true tuffs and porphyrites of the Tuff Formation, with a
dike of cataclastic diorite-porphyrite at V. 269.

From Camajuani to Falcon (See Section VIII) we begin with
Aptychi I.imestones that are steeply folded, with a general strike of N. 100 E.
At L. 407 we pass a bed of sandstone comparable t© that of V. 186. At L. 408
we pass into the Tuff Series, spilitic rocks and porphyrites with intercalated
beds of Hmestone. At L. 414 these are covered by tuff-breccias and tuffaceous
limestones, with abundant Orbitoids of the genera Pseudorhitoides and
Torreina (See fig. 12, p. 45). These beds belong to the Habana Formation,
and pass with a sharp boundary into a small zone of Serpentines, that clearly
has been under considerable stress, as the rocks are well bedded with a
strike of N. 135 E. and a steep southern dip. Just before crossing the sugar-
railroad at L. 420 we reach the Aptychi Limestones of the Loma Santa Fe,
and we remain in steeply folded well bedded limestones with lenses and
layers of chert and many veins of calcite, until we reach the southern
side of the hills near Santa Clarita, where once more the Serpentines begin
abruptly. Along the contact of Serpentines and Aptychi Limestones are
located various 'Chapopotes', small findspots of asphalt. These we can
explain by surmising that the Aptychi Limestones are an oil-motherfor-
mation. These limestones locally carry abundant Radiolaria and Smaller

Foraminifera and in some places even show traces of oil. During orogenesis
the limestones were folded and the Serpentines were brought into contact
with the limestones by an overthrust fault, which runs along the Loma
Santa Fé with a southwestern dip. Oil accumulated from the folded lime-
stones against the overlying less pervious Serpentines, and could escape
only along the plane of the overthrust.

Santa Clarita lies in the Serpentines that are found till near the Carretera
Central, where we pass into the Tuff Series.

From Camajuani to Placetas, we follow the railroad over San
Andres and begin with the Aptychi Limestones, but soon pass into brecciated
limestones of the Habana Formation, with, at A. 369, a conglomerate with
boulders of porphyrite, tuffs of the Tuff Series and Aptychi-limestones.
At A. 372 we have once more crossed the boundary and find porphyrite-tuffs
without stratification. To the left is a small hill, with brecciaceous white
and yellow limestones of the Habana Formation, carrying Orbitoids and
Vaughanina cubensis (A. 373, 374), The Tuff Formation is interrupted at San
Andres by a large patch of Dioritic rocks (See Section IX). We find here
diorites, diorite-porphyrites, amphibole-porphyrites and malchites, with
occasional serpentines. All dioritic rocks have undergone considerable stress,
and show strong cataclastic structure with broken phenocrysts and myloniti-
sation of the matrixes. Passing the Diorites we again get Tuffs until we
reach the Aptychi Limestones of the Loma Santa Fé at M. 456. On a more
western tracé we find the limestone-tuff boundary located a little more
to the North. This may be due to small tranverse faults or to the thinning
out of limestone beds. At the southern side of the Loma Santa Fé we once
more find the Serpentines till we reach Placetas.

From Santa Clara we pass white marls and oolithical limestones, where
we did not find any index fossils, till reaching the Serpentines. Hereafter
we pass a zone of Aptychi Limestones, that are strongly folded, and again
come into the Serpentines, that are replaced by Aptychi Limestones and
cherts near H. 500. Here again comes a small zone of Serpentines near
H. 502, whereupon we soon reach the Aptychi Limestones again. Just before
Encrucijada we find calcareous sandstones and, at the northern side of the
village, white brecciated limestones from the Habana Formation, with
fragments of Rudists. From here northward we find white, cristalline or
brecciated limestones, without fossils.

We have found on this section several alternating zones of Serpentines
and Aptychi Limestones, without seeing anything definite of the structure
of the limestone ranges and the serpentine fields. Although the Serpentines
are the younger, there is never any sign in the limestones of a metamorphism
caused by the Serpentines, which points to the fact that their contacts are
purely tectonical. We might yet think that the country was built up by

alternating synclines and anticlines with Serpentines in the synclines and
Aptychi Limestones in the anticlines and with small overthrusts at their
contacts, but then we should expect that the lateral endings of the limestone
ranges were caused by axial dippings of the anticlines. If then a range of
limestones ends, as it does for instance near Hatillo, the Serpentines should
more or less surround the end of the limestones, as the syncline becomes
wider with the dipping of the anticline. This is not the case. For instance
both northeast of Hatillo, and at M. 510 Northwest of the section from
Santa Clara to Encrucijada, we find the limestones ending abruptly against
the Serpentines. So we must surmise that the country is built up by a series
of wedges, where the older Aptychi Limestones are thrown up over the
Serpentines, whilst the lateral ends of the limestone ranges are formed by
tranverse faults. In most cases the direction of the dip of the overthrusts
is not seen. Only sometimes, for instance near Santa Clarita, where
asfalt deposits have formed at the contact between Limestones and Ser-
pentines, we are sure that the plane of the overthrust dips towards the
Serpentines.

To reach San Antonio de las Vueltas (See section VI), we leave the
road for Encrucijada just before H. 513 and cross a broad zone of Serpen-
tines, with many dikes of gabbros and with foreign inclusions, such as
amphibolites. Just before crossing the Rio Sagua la Chica at L. 499, we
reach the well bedded steeply folded limestones and cherts of the Aptychi
Formation, that form the Loma Purial. This ridge of hills lies just in the
prolongation of the Loma Santa Fe. On the eastern side of the Loma Purial,
after crossing the Rio Camajuani, we pass at L. 501 directly into the breccia-
ted steeply folded limestones of the Habana-formation, with characteristic
Orbitoids and Vattghanina cubensis. Just before San Antonio many fragments
of Rudists are found. Two small synclines, with grey marls and white or
grey, finely conglomeratical Upper Eocene limestones, carrying Discocyclina
and Dictyoconus, are found at L. 504 and L. 507.

If we compare the structure on this section with that found at the
road from Santa Clara to Camajuani, we find the latter much more
complicated. On the section through the Loma Purial we find neither a
zone of Serpentine, nor a layer of Flabana limestones intercalated between
the Aptychi Limestones. As Loma Purial and Loma Santa Fe lie in a
line with each other and parallel to the general strike predominating in
the Aptychi Limestones, I have connected both zones of limestones on
the map, whereas the zones of Tuffs, Serpentines and Habana Formation
found to the West of Camajuani, are thought to wedge out towards the
North. The possibility remains that the two limestone ridges are separated
by a band of Serpentines that should run through the topographical gap
between the hills and connect the large field of Serpentines to the West
of the hills with the band of Serpentines found at V. 189 and L. 419.
The two synclines with Upper Eocene West of San Antonio de las Vueltas
cannot be traced laterally.

The railroad first runs through Serpentines, that are replaced between
km. 285 and km. 286 by glass-tuffs and tuff-breccias of the Habana For-
mation and by radiolarian-tuffites with intercalated radiolarian limestones
of the TufF Formation between km. 282 and km. 281. Just before km. 280
tertiary oolithical white limestones containing Lepidocyclina with a North—
South strike and eastern dip cross the railroad (M. 556), to be followed in
the neighbourhood of km. 280 by limestones with abundant Rudists and
other fossils typical of the Habana Formation (H. 550). Limestones and
lightgreen fine-grained glass-tuffs follow, till we find a patch of dioritic rocks
between km. 278 and km. 277, where diorites and diorite-pegmatites are
found.

About two kms. futher West we cross toward the Carretera Central
that runs close to the rail and find at H. 636 large rocks of greyish, somewhat
conglomeratical limestone with Asterocjclina and abundant specimens of
Camerina maggillavrji. The microspheric specimens of this form attain the
large diameter of 5 cm.

The Carretera Central from Santa Clara to La Esperanza runs entirely
through Serpentines, with a dike of albitite at L. 351 and many dikes of
olivine-gabbros between L. 353 and L. 356. Here are found Dioritic rocks,
augite-diorite and albitite that probably are connected with those found
along the railroad.

South of the Carretera Central are some limestone hills, where lime-
stones, tuffaceous limestones and light-green glasstuffs of the Habana For-
mation outcrop. These glass-tuffs and tuffaceous limestones can be dis-
tinguished from those of the TufF Formation by the intercalated marls and
their lighter green colour, whilst under the microscope angular fragments
of quartz and specimens of Vaughanina cubensis are found to occur. These
are lacking in the tuffs and limestones of the Tuff Series, whilst radiolarian
deposits, that are frequently met with in the older sediments, are not found
here in the Habana Formation. Locally the limestones contain abundant
Orbitoids of the genera Orbitoides and Lepidorbitoides (L. 485, H. 153).

La Esperanza — San Diego del Valle — Cifuentes — Sagua
la Grande — Quemado de Guines.

The railroad from la Esperanza northward crosses low country, where
white marls are exposed. At Conyedo we see to the West a hill, which is
the end of a long cuesta, that forms the northern boundary of the Upper
Eocene against the older formations. Here at Conyedo the age of the lime-
stones is ascertained by corals {Monticulastrea regularis md Diplochaetetes
longitubus at H. 121) and by Foraminijera {Camerina sp., Discocyclina sp. at
V. 328). The limestones contain many boulders from the older formations,
for the greater part amphibohtes, actinolite-schists and other resistent inclu-
sions from the Serpentines. From Conyedo the railway turns Northwest and

follows the foot of the hill. Although no exposures were found, we may
assume it runs through Serpentine, which is found in good exposures more
to the East (V. 319—327). Before reaching San Diego del Valle, we pass
into the porphyrites of the Tuff Series at A. 410, that are replaced by a
band of Serpentines, chiefly recognised by its more resistent foreign in-
clusions, such as amphibolites and schists. We then pass into steeply and
irregularly folded, well bedded grey limestones, with occasional beds and
lenses of chert, of the Aptychi Formation. These are found till near Cifuentes,
where several beds of calcareous sandstones — with fragments of quartz,
plagioclase felspars, muscovite, grains of quartzite and mica-schist — are
intercalated in the greyish and blue, Radiolaria bearing Aptychi Limestones.

Cifuentes lies in broad alluvial plains of the affluents of the Rio Sagua
la Grande. North of Cifuentes, till beyond Citio Grande, we cross a low
ridge of hills, formed by steeply folded, well bedded limestones and occa-
sional cherts from the Aptychi Formation. From the railroad crossing at
Corazon de Jesus onward, till we reach the Rio Sagua la Grande, we follow
the northern slope of the hills just crossed. The hills are formed by Aptychi
Limestones with Ammonites at H. 487—489, whereas along the road we
find very weathered Serpentines and green weathered tuffaceous rocks, that
on microscopical examination are seen to be uralitized diabases, inclusions
from the Serpentines. On the northern bank of the Rio Sagua la Grande
we find brecciaceous, white or grey limestones from the Flabana Formation,
with Orbitoides bronmi at V. 252 and white limestones with many organisms
from the Upper Eocene, containing Dictyoconus fontabellensis, at V. 255.
The limestones are placed vertically, with a general strike of N. 100—110 E,,
which strike is the same as that of a ridge of hills beginning at these two
localities and extending South from the road from Sagua la Grande to
Quemado de Guines.

From the northern side of this ridge over Sagua la Grande, till we
reach the sea at La Isabella, we pass low lying land with horizontal, cavernous
limestones, probably of Oligo-Miocene age (Guines Limestone), probably
younger.

In following the road from Sagua la Grande to Quemado de Guines,
we pass again the Upper Eocene, Habana and Aptychi Formations, whilst
at A. 428 to the northern side of the road lie several small, isolated hills.
We did not find fossils here, but through the courtesy of the 'Bataafsche
Petroleum My' at the Flague I received samples of limestones with fragments
of Rudists of the Genus Sauvagesia collected on the same spot. These prove
that here again Cretaceous — and most probably Habana — Formations
outcrop.

Before reaching Quemado de Guines, we pass from the Aptychi lime-
stones and cherts into white and yellow, coarsely brecciated limestones,
without fossils, that most probably belong to the Habana Formation. South
from Quemado de Guines we find at L. 530 and L. 531 horizontal, white
and red cavernous limestones, with a very characteristic habit, caused by

moulds and casts of abundant Gastropods, whose shells have been totally
weathered out. We did not find any complete fossils in this Guines Lime-
stone, but we may place it with Palmer (9) as Oligo-Miocene.

South of Jicotea, near the cemetery, we find in an outcrop of conglo-
meratical marly limestones with a small northern dip, abundant larger
Foraminifera of the genera Camerina, Heterostegina, Lepidocyclina, Helicolepidina
and Discocjclina, indicating an Upper Eocene age of these beds.

In leaving Jicotea to the Northeast, we find marls and limestones,
with occasional Orbitoids and corals. At H. 392 we are at the northern
limit of the Eocene. It forms here a low hill, gendy sloping to the South,
but forming a cuesta toward the plains at the northern side. To the left
and right, we see how this limestone-hill continues along the northern limit
of the Upper Eocene, and that it is connected with the cuesta we found
between La Esperanza and San Diego. In the basal parts the Eocene is
conglomeratical here also, but, whereas near Conyedo most pebbles were
derived from the Serpentines, we find pebbles of radiolarian limestones and
cherts from the Aptychi Formation predominating here. From FL 392
onward, till we reach San Diego, we pass low lying country, with brownish
green glass-tuffs and radiolarian tuffites from the Tuff Series cropping out.

The country South from the Carretera Central, between
Santo Domingo and La Esperanza.

At A. 360 and in the neighbourhood of Santa Isabel (L. 156, 157, and
H. 71, 80) we find specimens of Lepidocyclina, typical of the Olicogene ;
whereas at A. 361 and at L. 158, H. 61, H. 63 and H. 66 faunas of Larger
Foraminifera, typical of the Upper Eocene, are found. Near Santa Isabel
the beds are feebly folded with a general northwestern dip. Oligocene and
Upper Eocene seem to be perfectly concordant, and are not to be dis-
tinguished lithologically. They consist of white marls and marly limestones,
alternating with finer and coarser soft greyish conglomeratical limestones,
with well-rounded small pebbles of limestones and weathered tuffoid rocks.

East from Santa Isabel, till we reach the eastern boundary of the Ter-
tiary against the Habana Formation and Tuff Series near San Juan (de los
Yeras), we find white marls and marly limestones, with low dips and varying
strikes in gently undulating structures. Sometimes these rocks are sterile,
sometimes they are seen to contain abundant Smaller Foraminifera that
could not, however, be determined specifically. At A. 126 we again find
specimens of Discocjclina, which mark the eastern limit of the Upper Eocene,
as we find tuffites and glass-tuffites of the Habana Formation directly east-
ward (A. 138), with limestones containing abundant Rudists at H. 196.

We begin with Serpentines and pass to the northern side of a large
patch of intrusive dioritic rocks, that form a white hill, standing out clearly
in the brownish-red serpentine country. It consists (A. 391—399) of diorites,
diorite-porphyrites and albitites, that show evidences of having been under
considerable stress. Several rocks have a strongly cataclastic structure,
whilst in those where this is not the case the quartzes show anomalous,
undulous extinction.

At L. 535 we pass into a small zone of limestones, carrying remains of
Ammonites. The limestones are intercalated in rocks from the Tuff Series.
These comprise green tuffs and tuffites, with a southern dip. The deter-
mination of the Ammonites by Prof. Jaworski has yielded species occurring
elsewhere in the Turonian or the Emscherian, so we may date the sediments
at the boundary between these two formations ; that is to say, between
the Middle and Upper Cretaceous. In the field the pétrographie character
of the well-bedded, fine-grained limestones is identical with that of the
Aptychi Limestones. The latter are, however, of Lower Cretaceous age,
and alternate with rocks from the Tuff Series of much deeper zones.

The highest beds of the Tuff Series are exposed between L. 538 and
L. 540. They are formed by grey, thick-bedded radiolarian limestones,
which are directly overlain by coarse green Habana tufBtes, characterised
by large fragments of clear basic plagioclase felspars and quartz, together
with fragments of light-green augite and grains of magnetite, with a glassy
matrix. Till South of Bernia we find outcrops of green tuffs and tuffaceous
limestones, alternating with pure limestone-beds, that frequently contain
Rudists. In the neighbourhood of Bernia the beds have a northern dip and
consequently more to the south at H. 198 we find the porphyrites and tuffs
of the Tuff Series again, that are overlaid at H. 196 by Habana Limestones
with Rudists and a sill of augite-porphyrite at H. 213. We thus find the
Habana limestone in a large syncline, that can also be traced further East,
between Santa Clara and Seibabo (See section II) and between Santa Clara
and Provincial. Here it has become much smaller, and we could not trace
it further eastward. If, in the syncline at the section over Bernia, we try
to connect different layers of the northern and southern flanks, we fail to
do so, as the single series of observations taken is not enough. The southern
flank is much thicker and we can explain this in two ways. First there might
be an overthrust, in the northern flank, by which part of the Habana For-
mation could be concealed. This is not very probable taking into account
the general appearance of the structure, which, with its gentle dips, does
not suggest anything so violent as overthrusting. Secondly, we may explain
the difference, by the thinning out of the beds towards the North, which
is very probable in a series of beds, whose lithology (Rudists, large angular
tuff fragments) suggest a littoral sedimentation, and becomes even more so

in connection with the fact, that the Habana Formation is transgressive
over the older TufF Series.

From Baez to Guaracabulla, we pass through the TufF Series and find
porphyrites and, locahy, well bedded tufFs, with a dike of augite-diorite-
porphyrite at L. 519. In this neighbourhood the tuffs have a general strike
of N. 95 E. and a northern dip.

North from Guaracabulla we find green tuffs and glass-tufFs with
concordant layers of porphyrite. General strike is about N. 110 E. with a
southern dip. Guaracabulla thus lies in a synclinc, which most probably is
the same structure as the Habana-synciinc further West, although its axis
here has become so high that no more Habana Formation rocks are found.
From M. 402 onward we find weathered green rocks, which on micro-
scopical examination are found to be silicified spilites. They have the same
texture as the true spilites, with small, twinned cloudy laths of acid plagio-
clase felspar, irregularly lying in all directions. But most of the pyroxenes
are altered into chlorites, whilst on many places secondary patches of quartz
are seen, intergrown with chlorite, calcite and epidote or zoisite ; thereby
proving their secondary nature. We may regard these rocks as normal
spilites from the TufF Series, that have become silicified by the dikes of
diorite, that are found at M. 407. This locality is an abandoned gold mine,
the Mina Isel.

We find here Dioritic rocks, such as diorite and diorite-porphyritc,
close to the same sihcified spihtic rocks. The works being abandoned,
nothing can be said about the underground structure, but all the waste
lying around consisted of Dioritic rocks, so we may safely assume the
diorites were the bearer of the ore.

Immediately North from the Mina Isel begins a bare hill, formed by
Serpentines, that is to be seen running through the country, with a general
East—West strike. More to the West, we find the same contact, between
Tuffs and Serpentines, along the southern side of the Serpentine-formed
Sierra Alta de Agabama. Here we find tuffoid rocks with strikes, that are
cut off by the contact between Serpentines and TufFs, which proves this
contact to be tectonical. We may safely assume the same between Guaraca-
bulla and Falcon, although in the spilitic rocks South of the contact no
stratification is found. So the intrusion of the Diorites has followed the
plane of faulting, by which the older TufF Series and Serpentines were
brought into contact.

The Serpentines are replaced by spilites from the TufF Series before
M. 412, At M. 416 these rocks are again sihcified, and between M. 416 and
M. 419 we find Dioritic rocks, consisting of dikes of albitites and amphibolc-
albitites, that account for the sihcification in the spilites. Well bedded

brownish or green very fine grained radiolarian tuffites, with occasional
interbedded diabases or spilites follow in a synclinal structure, till we reach
Serpentines, with a dike of malchite at M. 434, just before the railway
station of Falcon.

More eastward, the second zone of Tuffs is also found Southwest of
the Carretera Central (See section IX). Flere it contains limestones with
Ammonites at M. 604. The well bedded limestones are identical in pétro-
graphie character with those from the Aptychi Limestones, but the Ammo-
nites found indicate a much younger age, e. g. the boundary between Middle
and Upper Cretaceous (Jaworski in litt.).

In this neighbourhood we also find at M. 613 the asfalt mine Anna
Maria. The asfalt is found in two main bodies, at the contact of Tuff Series
and Serpentines, which stikes N. 130 E., with a steep western dip, and must
have accumulated along an overthrust-pJane between the two formations.
The rocks of the Tuff Series, that outcrop here, are unstratified tuffs, with
many sills and dikes of porphyrites, and as such cannot be considered as
producers of the asfalt. This has probably come from limestones, inter-
calated in the Tuff Series lower down, whilst the only means of escape was
through fissures along the contact between the more or less impermeable
rocks from the Serpentines and from the Tuff Series. In general the rocks
of the latter formation ; being well stratified and folded, will be reasonably
permeable. In this particular case however, with the local abundance and
diversity of porphyrites, there might not be a great difference, as to permea-
bihty, between the Tuff Series and the Serpentines.

The existing literature on the geology and paleontology of Cuba is
rather large and scattered, but mostly of a very summary character. It will
not be reviewed here in full.

There are several general reports on Cuban geology (Hayes, Spencer
amp; Vaughan, bibl. 5 ; de Golyer, bibl. 2, and Whitney Lewis, bibl. 6),
containing descriptions of the stratigraphy and tectonics of the island.
Their more detailed descriptions, however, mostly are of other provinces,
mainly Habana, Matanzas, Pinar del Rio and Oriente, whereas for Santa
Clara only general statements are made. Moreover their stratigraphie divi-
sions are largely based on local sections, with stress laid on local pétrographie
characters, without stating definitely the paléontologie evidence for the
divisions made. For these reasons it would have been doubtful if, by applying
old names to the divisions I made in Santa Clara, the statigraphic elements
named would be the same as with the older authors. For these reasons,
I have not taken into account these older geologic descriptions, and have
given an account of the geology of the district only, as it appeared from
our own observations.

Palmer (bibl. 9.) recently gave a detailed description of the geology
in the vicinity of Habana City. Although the geographic distance between
Habana City and Santa Clara is rather large, it was clear from the detailed
description of the formations, coupled with the fauna Palmer mentions,
that his formational divisions are parallel to those I made in Northern
Santa Clara. For these reasons I have used the names of Habana Formation
for the transgressive sediments of Maastrichtian age, and of Guines Lime-
stone for the Oligo-Miocene, horizontal, cavernous limestones, found South
of Quemado ; as Palmer's description of these formations are taken from
localities where they are of typical habit and common occurrence.

The other formational names used by Palmer I intentionally omit-
ted, as the outcrops of these formations, found in the vicinity of Flabana
are of local extent, whilst it is not certain that their habit is representative
of Cuban deposits. Until more is known of Cuban geology, I preferred to
use stratigraphical names instead of formational names.

ScHURMANN (Bibl. 12), vcry recently published descriptions and analyses
of Cuban rocks, with some general statements on Cuban geology. His views
differ in several respects from mine, but he does not give geologic evidence
for his statements, whilst his find-spot-map is on too small a scale for
accurate use. Serpentines are given as syn-orogenetic, and in Habana Pro-
vince he assumes a second younger sequence of Serpentines. But in the

pétrographie descriptions a serpentine from the Tuff Series is described also.
Stress is laid on two points, which I wish to contend. The Diorites are
given as mainly post-orogenetic, in contrast with the syn-orogenetic Ser-
pentines. From the description of the Diorites in this paper it may be seen
that these rocks mostly show signs of a cataclastic structure, which in many
rocks is very apparent and sometimes becomes predominant. Good, unshea-
red, dioritic rocks are rare in the district, so we may place them with the
syn-tectonic Serpentines.

Schürmann parallelizes the intrusion of the Serpentines and the later
Diorites with the strongest orogenetical phase, before the sedimentation of
the Upper Cretaceous. From our observations, it is clear, that this phase
was not very strong, compared with the post-Cretaceous phases, which for
a large part were responsible for the forming of the imbricate structure
of the island.

(1.) Cushman, J. A., 1920 : The american Species of Orthophragmina and
Lepidocyclina.

U. S. Geol. Surv. Prof. Paper, 125 — D.
(2.) de Golyer, E., 1918 : The Geology of Cuban Petroleum Deposits.

Bull. Am. Ass. Petr. Geol. Vol. 2.
(3.) Geyn, W. a. E. van de, and Vlerk, L M. van der, 1935 : A mono-
graph on the Orbitoididae, occurring in the Tertiary of
America.

Leidschc Geol. Med., Vol. VII, No. 2.
(4.) Gravell, D. W. and Hanna, M. A., 1935 : Larger Foramuiifera from
the Moody's Branch marl, Jackson Eocene of Texas, Louisiana
and Mississipi.

Journ. o. Pal., Vol. 9, No. 4.
(5.) Hayes, C. W., Vaughan, T. \V. and Spencer, A. C., 1901 : Report
on a geological reconnaissance of Cuba. Made for the Military
Governor. Washington D. C.
(6.) Lewis, J. Whitney, 1932 : Geology of Cuba.

Bull. Am. Ass. Petr. Geol., Vol. 16, No. 6.
(7.) Niggli, p., 1927 : Zur Deutung der Eruptivgesteinsanalysen auf
Grund der Molekularwerte.
Schweiz. Min.-Petr. Mitt. Bd. VII, Heft 1.
(8.) Palmer, Dorothy K., 1934: The occurrence of fossil Radiolaria
in Cuba.

Mem. Soc. Cubana de Hist. Nat,, Vol. VIII, num. 2.
(9.) Palmer, R. H., 1934 : The geology of Habana, Cuba, and vicinity.
Journ. of Geology, Vol. XLII, No. 2.
(10.) Rutten, L. M. R., 1934 : Geology of Isla de Pinos, Cuba.

Kon. Akad. Wet., Amsterdam, Proc., Vol. XXXVII, No. 7.
(11.) Rutten, M. G., 1935 : Larger Foraminifera of northern Santa Clara
Province, Cuba.

Journal of Pal., Vol. 9, No. 6.
(12.) Schürmann, H. M. E., 1935 : Massengesteine aus Cuba.

Neues Jahrb. f. Min. etc.. Beil. — Bd. 70, A.
(13.) Trauth, F., 1936 : Ueber Aptychenfunde auf Cuba,

On the geologic map a small area of Turonian-
Emscherian Limestones, South of the Carretera
Central between Placetas and Falcon is indi-
cated with a green instead of a blue colour.

In the figures of the microscopic thin-sections, arrows indicate the position of various minerals.

If a crystal lies close to the boundary of the figure, one arrow is used, otherwise it can be found at

the point of intersection of two arrows with the same letter. Figures 1, 2, 3, 7, 8 and 9 are made with

fig. 1. Spilite from the Tuff Series, with small phenocrysts of cloudy, acid plagioclase felspar, x 15.
Locality L. 411, South from Camajuani.

fig. 2. Schistose Serpentine, built up by antigorite and small patches of bastite, for instance at a.

X 9. Locality H. 425, Southwest from Santa Fé, at the contact of Serpentines with Aptychi
Limestones.

fig. 3. Schistose Eclogitc, a foreign inclusion from the Serpentines. Schistose groundma.ss of omphacite,
with idiomorphic crystals of garnet and prisms of green amphibole, for instance at a—d. X 15.
Locality H. 531, Southwest from Santa Fé.

fig. 4. Albite-chloritc-cpidotc-muscovite-schist, a foreign inclusion from the Serpentines, with clear,
poikilitic albite, epidote in small grains (dark), aggregates of greenish chlorite (a), prisms
of zoisite (c), and tables of muscovite (/gt;). X 13. Locality H. 115, foreign inclusion from the
Serpentines, found as boulder in the Upper Eocene basal conglomerate near Conyedo.

fig. 5. Epidotc-Amphibolite, a foreign inclusion from the Serpentines, being built up by green
amphibole and epidote in irregular crystals, with some titanite (at a) and a small amount
of clear albite. X 16. Locality H. 502, South from Encrucijada.

fig. 6. Zoisite-Amphibolitc, a foreign inclusion from the Serpentines, with green amphibole [a)
and prisms of zoisite {h) and a rather large amount of poikilitic, quartz-clear albite, with
rare leaves of muscovite (c). X 15. Locality H. 412, East ''rom Santa Clara.

fig. 7. Gabbro, a dike in the Serpentines, with coarsely granular structure, built up by basic plagio-
clase felspars and rhombic pyroxenes, for instance at a and b. X 15. Locality V. 164a, East
of Santa Clara, on the road to Remedios.

fig. 8. Olivine-Gabbro, a dike in the Serpentines, differing from the Gabbros by the presence of
olivine {b and t). Rhombic pyroxene at a. The felspars show lamellar twinning. X 15. Locality
L. 355, on the Carretera Central, West of Santa Clara.

fig. 9. Sheared Quartz-Diorite, with cloudy, acid plagioclase felspars at a and b, amphibole at c,
quartz at d and a shearing-zone indicated at e. X 15. Locality M. 465, near San
Andres.

fig. 10. Colony of Diplochaetetes longitubus Weissermel. Polished surface at the left side of the coral.
a. : Point of attachment. Locality H. 121, near Conyedo. X 1,4.

fig.l 1. Monticulasirea regularis Kühn. Polished surface showing at the right side of the photo. Locality
H. 121, near Conyedo. X 2.

■ ■ ^ .

D. K. Palmer: The occurrence of fossil Radiolaria in Cuba.
Mem. Soc. Cubana de Hist. Nat. VIH, 1934.

Thalmann's voorbeelden van een invoering der trinaire
nomenklatuur bij fossiele Foraminiferen zijn onvolledig en
ten deele onjuist.

Thalmann : Über geographische Rassenkreise bei fossilen
Foraminiferen. Paleont. Z. 16, 1934.

De opstelling van het genus Orhitoina van de Geyn en
van der Vlerk geschiedde op onjuiste en onvolledige
gronden.

Van de Geyn en van der Vlerk: A monograph of the
Orbiloididae, occurring in the Tertiary of America. Leidsche
Geol. Med. VII, 1935.

P. Pijpers: Geology and Paleontology of Bonaire (D.W.n
Utrecht 1932.nbsp;^nbsp;V

Berek's bezwaren tegen toepassing der methode van
Fedorow bij mineralen met hooge dubbelbreking zijn on-
gegrond.

■ /Ä

b-v/l/-.r;'nbsp;(fnbsp;/l -

^..^„y-'.J,:-.

Het bestaan van een ,NormaIzugrichtung' (Geyr von
Schweppenburg) wordt door het verloop van de vogeltrek
over Nederland niet aangetoond.

Symmetrische rangschikking der mineralen in metamorphe
gesteenten is geen bewijs voor het ontstaan dezer regehng
door inwendig glijden van het gesteente (Durchbewegung).

Met behulp van de vloeidruk verklaart men op de aan-
nemelijkste wijze de mogelijkheid van het schaatsenrijden.

Het zwaartekrachtsveld in de Maleische Archipel wordt
door van Bemmelen op aannemelijker wijze verklaard dan
door Vening Meinesz.

R. W. van Bemmelen: Über die Deutung der Schwerkrafts-
anomalien in Niederlandisch-Indien. Geol. Rundschau,
XXVI, 193.').

rt^lltf,

. quot;ï

N^sE.
Plaza, 3a77^a C^ara '

Piaza '^ania Ciara

* • • « •

Sar? flnionio

Upper focene.

-L—J Ha dan a rorr??a/iof7.
Dior/he Inirus/ons.
SerpeniirJes.
^piychi Limesiones.

Sarr/a Clariia

WSk Tuff Ser/es.

Tu?-or?/ar2-Fmscherian
Li777esfo?7es.

Pail roact.

Cor-re/era
Central

San /indres
t

TT TT

• • • • •

JSzsW.
Jicjuima

N36E.
Jarahueca

J Am.

These /a/eaZ sec/ZorfS are sc/?e^?7a//c lt;2rF(/or?/j/ seri/e /o^/ye /lt;/ea a/Zhe /a/yep- s/rac/ures.

		.'lt; -' - - ■



		.- 'f.. ,,
	-;quot; -;

———.—	- r-

Nr.:		2.	3.	4.	5.	6.	7.	8.	9.
Analyst: W. van Tongeren
SiOa	74,48	67,37	63,90	60,11	50,71	48,54	39,75	55,50	56,00
AloO«	12,47	15,95	14,56	16,55	16,72	12,02	0,57	15,25	19,09
FcsOs	2,30	1,09	3,01	2,81	0,99	2,57	7,40	2,45	1,15
FeO	0,42	1,61	2,56	5,46	7,01	7,91	0,95	3,79	6,14
AlnO	tr.	0,02	0,05	0,02	0,06	0,18	0,08	0,07	0,18
MgO	0,22	1,26	2,57	2,41	6,91	12,35	37,79	7,73	4,63
CaO	1,41	2,65	3,34	6,09	6,62	14,14	0,03	4,70	4,25
Na^O	2,88	5,40	4,23	4,08	4,72	0,68	0,14	5,60	4,27
KgO	4,51	1,90	2,85	0,84	0,28	0,20	tr.	0,68	1,32
H2O	0,39	1,25	1,63	0,52	4,67	0,86	12,10	2,54	1,45
H2O-	0,48	0,54	0,43	0,20	0,96	0,13	0,78	0,86	0,77
TiO,	0,33	0,38	0,50	0,72	0,39	0,31	0,03	0,74	0,72
CO2	tr.	0,04	—	0,05	tr.	—	tr.	—	0,03
P2O,	0,12	0,33	0,42	0,24	0,15	0,17	0,07	0,14	0,08
Ct'A	—	—	—	—■	tr.	—	0,32	—
Total	100,01	99,79	100,05	100,10	100,19	100,06	100,151)	100,05	100,08
			Niggli-		values:
si	440	297	243	194	131	97	63	152	165
al	43,3	40,3	32,5	31,6	25,4	14,1	0,7	24,6	33,3
fm	14,2	17,8	31,4	33,1	44,0	54,1	99,0	45,5	38,6
c	9,0	12,5	13,6	21,0	18,3	30,2	0,05	13,8	13,4
alk	33,5	28,4	22,5	14,3	12,3	1,6	0,25	16,1

Nr.:	10.	11.	12.	13.	14.	15.	16.	17.
Analyst: W. van Tongeren
SiOa	53,19	47,58	46,20	46,91	68,77	51,41	69,25	62,15
AI2O3	15,14	14,07	14,74	17,69	15,68	15,60	14,27	13,13
Fe,03	3,84	1,33	3,56	2,65	0,67	2,18	1,83	3,06
FeO	8,25	10,05	6,28	9,43	1,42	6,46	1,76	0,49
MnO	0,07	0,12	0,09	0,06	—	0,08	0,02	0,03
MgO	2,62	3,84	8,18	4,02	1,97	7,66	0,50	1,35
CaO	6,80	13,12	12,42	9,61	2,54	11,28	3,01	3,44
Na^O	4,57	3,47	4,81	5,36	6,80	2,60	3,78	1,63
Ko	1,28	1,01	0,23	1,28	1,47	0,28	4,08	2,88
H2O	1,80	3,29	0,83	1,26	0,60	1,07	0,28	8,03
HaO-	0,81	0,41	0,24	0,33	0,13	0,34	0,49	3,34
TiO^	1,28	1,35	2,09	1,66	0,26	0,66	0,52	0,40
CO.	tr.	tr.	tr.	tr.	0,02	0,13	0,17	tr.
P2O,	0,06	0,02	0,09	tr.	tr.	0,18	0,16	0,06
SrO	0,08	0,12	0,11	0,06	—	—	—	0,04
Total	99,79	99,78	99,87	100,32	100,15	99,93	100,12	100,03
			NiGGLi-values:
si	151	114	98	110	288	121	322	317
al	25,3	19,9	18,5	24,2	38,7	21,7	39,1	39,4
fm	39,1	36,6	43,0	37,4	18,4	43,5	16,8	24,2
c	20,7	33,8	28,3	24,1	11,4	28,4	15,0	19,0
alk	14,9	9,7	10,2	14,1	31,5	6,4	29,1	17,4

L. 373,	L. 483, L. 505,	H.	143,
PL 482,	H. 550, H. 640,	V.	151,
V. 188,	V. 229, A. 330,	A.	331,
A.373,	M. 573, M. 793.
L. 451,	H.640, V. 151,	A.	374.
L. 396,	L.485, L.501,	H.	153,
H. 157,	H. 160, V. 159, V.		252.
L. 505,	H. 482.
H. 153.
L.415,	V. 188.
L.485.
L. 485.
L. 485,	H.153.
L. 485,	H. 153.
H. 153.
H. 143,	H. 157, V. 157.
V.227.
L. 414,	L.415, L.417.

Height............	1,0	1,1	1,2	1,6	1,8	2,3	2,4
Diameter at basis ...	1,8	2,1	1,8	1,6	2,4	3,7	3,0