26 Mr. R. C. Taylor's Notes relatme to the Geology of Cuba, 



assistance of the luxuriant foliage of certain creeping shrubs, or 

 an occasional tree growing amongst the recesses and crevices. 



The barometer being injured in the ascent, no correct cal- 

 culation was made of the height of La Silla, which we esti- 

 mated at from one thousand to twelve hundred feet above the 

 sea, here distant about eight miles. 



Contrary to our expectation, we found that the summit was 

 limited to a narrow ridge ; a mere vertical wall of honey- 

 combed limestone, on which it was practicable only in a few 

 places to obtain sufficient space for standing, assisted by the 

 shrubs that were rooted in the crevices. 



We have adverted to the singularly beautiful appearance 

 of these rocks when viewed either from the crest or from below ; 

 which effect was produced by the vertical wearing or erosion 

 of the white marble in grooves, giving them the aspect of 

 enormous columns and of gigantic groups of crystals. 



The upper surfaces of this rock are deeply honeycombed ; 

 that is to say, they have numerous sharp projecting points, on 

 which it is dangerous to walk, and have also innumerable cir- 

 cular holes two or three inches in depth and one inch or more 

 in diameter, perfectly smooth and regular in their interior, as 

 if bored with an auger. 



No stratification can be perceived in this enormous mass of 

 limestone. Certain lines of separation there are, which may 

 be traced at various angles, as well as vertical fissures, but 

 none of these were the result of stratification. Large blocks 

 are commonly seen piled on the sides near the summits of 

 these mountains. They are remarkably sonorous when struck, 

 ringing under the blow of the hammer like a bell. 



Land-shell Limestone of La Silla. — We have adverted to 

 the barrenness of the white marble in organic remains, and 

 we obtained from hence only a single specimen, a madrepore, 

 which was somewhat modified in form. 



We have now to describe a deposit, rich in fossil shells, of 

 a novel and remarkable character. 



On the surface and on the sides of La Silla is a great abund- 

 ance of subsided masses of stalagmitical rock, derived from the 

 limestone, and filled with hollow casts of an immense assem- 

 blage of univalve shells, which at the first glance I thought 

 were tertiary. On examination these shells were observed to 

 be peculiar to a separate rock of a brick-red colour, but the 

 position of that rock was not immediately discovered. This 

 red earthy stone was also crowded with small spherical bodies ; 

 black, smooth, polished, with minute rounded and kidney- 

 shaped pebbles, from the size of mustard-seed to that of a 



