722 INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



absolute elevation of perhaps 300 feet. It occurred in a thoroughly hard rock, but this cir- 

 cumstance is in itself no proof of actual antiquity, since in a purely calcareous region such 

 as this one rock cementation is a rapid process, as we had occasion to observe in the terrestrial 

 (fossiliferous) Limestone now forming near a quarry about 2 miles south of Ticul. In the red 

 rock wliich in the cave of Calcehtok overlies the gray limestone I found the impression of a 

 single gastropod, which I should unhesitatingly refer to a terrestrial form and to a genus of 

 PupidiTe close to Macroceramus, if indeed it is not Macroceramus itself. I could find no ves- 

 tiges of marine mollusks, but yet they may weR occur in other parts of the rock and it would, 

 perhaps, not be safe to conclude that the entire red rock is of terrestrial origin, or that it rep- 

 resents a single type of formation. 



No doubt attaches to the heavily bedded gray and white limestones and marbles which 

 are so well exhibited in some of the deeper caves, such as that of Calcehtok, for example. The 

 mouth of this cave, according to a rough approximation, is some 200 feet above the sea. At 

 a depth of some 50 feet the red limestone appears in a solid mass, and beneath it we reach the 

 crystalline limestones, which are disposed in layers of 10 to 15 feet thickness. Fossils are not 

 abundant in this rock, and Col. Glenn, who had explored this cave on a previous occasion, was 

 of the opinion that no fossils were to be found in it. After considerable search, however, we 

 discovered a few in an indifferent state of preservation, and still later some whose characters 

 were sufBiciently defined to permit us to determine their relationship. Among these are a 

 Pecten, with little doubt Peden nucleus, the cast of a large Marginella, apparently the living 

 Marginella labiata, a Potamides or Cerithidea, the impression of the apex of a large OHva (of 

 the type of Oliva literata), and a single impression of Venus canceUata. While the above forms 

 are barely sufficient to determine the exact age of the formation in which they occur, whether 

 Phocene or Miocene, I am inclined to believe that it is rather the former, the mountain rock — 

 semicrystaUine or highly compact and but scantily fossiliferous — being a compressional altera- 

 tion of the much less compact and highly fossiliferous rock of the basal plains. But whether 

 Pliocene or Miocene, I think it can be all but positively assumed that it is not older than Miocene, 

 although it has been asserted that it represented the Oligocene or Vicksburgian period." 



F 17-18. CUBA. 



T. W. Vaughan has contributed to this work the following notes on the early- 

 Tertiary of Cuba: 



The only rocks that we positively know to be of Eocene age in the island occur in the 

 Province of Santiago, not far from the city of Santiago, where they are associated with man- 

 ganese ores. This information is furnished by William H. DaU, who determined some fossils 

 collected by Clarence Bang. Associated with the manganese ores in this province are forami- 

 niferal limestones and foraminiferal marls, which appear to be of Eocene age and are tenta- 

 tively referred to that epoch. It is probable that the limestones occurring along the northern 

 foot of the Sierra Maestra from Los Negros to Cabo Cruz are also Eocene. Eocene limestones 

 are reported from the Province of Santa Clara, particularly near Cienfuegos, from the Province 

 of Matanzas, near the city of Matanzas, and from the vicinity of Havana. The data on which 

 the age of these rocks has been determined for these three provinces seem doubtful, the doubt 

 for the vicinity of Havana being so strong that the formations in that area are referred to the 

 late Oligocene. 



North of the city of Pinar del Rio and along the Rio Santa Fe, just south of the village of 

 San Jose, sandstones underlie the upper Oligocene limestones. No paleontologic data by which 

 the age of this formation could be determined were procured, but it may be of Eocene age. 



A yellowish marl composed of the remains of Radiolaria has been described by several 

 authors as occurring in Baracoa. This material linderhes the upper Oligocene and is probably 

 of early Oligocene age. 



Limestones and marls of late Oligocene age constitute by far the most widespreaa geologic 

 formation in Cuba. They extend uninterruptedly from the Province of Pinar del Rio to the 



" Agaasiz, Alexander, Three cruises of the Blake, vol. 1, p. 69. 



