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co-operated in (he crnstal movements, in tlie South near Arroyo 

 Narranjo limestones are overlying the "Older Habanaformation", 

 vviiich are perfectly horizontal and can be traced southward as far 

 as Guira, invariably in horizontal position. Near Arroyo Narranjo 

 tliese linjestones, which in their habitus differ greatly from the 

 rocks of the "Older Habanaformation", are coastal limestones; 

 farther to the south also Globigerina limestones occnr. As a matter 

 of fact these limestones, which have had no share in the latest 

 orogenetic movements, must be of more recent date than the mio- 

 pliocene rocks of the "Yonnger Habanaformation" and belong con- 

 sequently to the Youngest Pliocene or Pleistocene. These limestones, 

 which the Geological survey-map of North-Amei-ica 'j still marks as 

 Old Tertiary, have lent support to the opinion that the Cuban 

 Tertiary is only feebly folded, and that the Tertiary constitutes only 

 a thin varnish overlying the older formations. 



This does away with the seeming contrasts between Cuba and 

 the other Antilles and leplaces the island in the homogeneous range 

 of the Antillean Cordillei-a. 



In an excursion to San Diego de los Bafios, about 100 k.m. to 

 the west of the capital I encountered also here a well-developed 

 and intensely folded eogene formation; to the North of this small 

 town mesozoic limestones emerge, but farther to the south intensely 

 folded rocks (strike E.-W.) are exposed everywhere — especially 

 submarine tuffs — containing Lithothamnia, Nummulites and Ortho- 

 phragminae. Globigei'ina marls also occur. 



The Petrographic composition of the Cuban Tertiary is interesting 

 also in other respects. First of all, in the Older as well as in the 

 Younger Habanaformation limestones occur that, being examined 

 microscopically, appear to contain much young volcanic material, 

 nay in many cases, even change into true calcite-poor, submarine 

 tuffs. Sharp angular splinters of plagioclase and quaitz are numerous. 

 Likewise numerous grains present themselves, of a substance con- 

 taining plagioclase microlites, granules of oi'e and glass, which are 

 to be considered as ground-mass fragments of an andesitic or dacitic 

 rock. Similar eogene, submarine tuffs were also recognized in the 

 Tertiary of San Diego. Much volcanic material also occurs in mio- 

 pliocene deposits of a shallow sea (coralligene limestones, marls, 

 calcareous sandstones and finely granular conglomerates), which are 

 excellently exposed in the Yumuri cleft near Matanzas, about 75 k.m, 

 east of Habana. On the contrary volcanic material seems to be 

 lacking entirely in the very young, horizontally disposed limestones 



1) B. Willis, I.e. 



