HILL: GEOLOGY OF JAMAICA. 151 
Guppy has described 250 species of “Tertiary fossils of the West 
Indian region” without giving definite localities or horizons, but we 
have reason for believing that a large majority of these come from the 
Bowden beds. Dall has recently deseribed! forty-eight additional 
Species from the “Oligocene of Jamaica,” which are all from the 
Bowden locality. 
No detailed list of the molluscan fauna of Bowden as a whole has 
been made,” although such a catalogue would be most important and 
Valuable, for with it the discussion of all great questions concerning the 
West Indian later Tertiary paleontology would be made intelligible, 
While now this subject is in a stage of mist and chaos. Dr. Dall has in 
his hands the material for such a catalogue, and it is sincerely hoped 
that he will make one at an early day. It is a well known fact that a 
“ge percentage of these Bowden forms have persisted through later 
times and aro at present living in West Indian waters, and that de- 
ductions concerning the Pliocene or Pleistocene age of the succeeding 
beds can be made only on the percentage of many forms. Without a 
census of the Bowden molluscan fauna, it must be evident that all such 
eductions as have been or will be made concerning this fauna are 
Wstablo, 
Dall correlates? this molluscan fauna with tho “ Chipola, Tampa, and 
"hattahoocheo horizons of Florida, corresponding to the Aquitanian of 
ance.” Ho also notes the wide occurrence of this fauna in the An- 
filles, Trinidad, and Curagoa, and on the mainland of Panama. A large 
Percentage of these forms still exist in the adjacent seas and represent 
* ancestral conditions of the present life. 
No traces of Pteropods were found in my examinations of any of the 
"os below the Bowden beds. In the latter numerous specimens of 
Small Pteropods about five millimeters in length appear. In these beds 
ere are also many specimens of a craniate shell attaining a diameter 
e half a centimeter which may belong to this order. Bagg has kindly 
identified the species as follows : Hyalæa gibbosa, Rang; Hyalæa lim- 
Ma, POrb.; Hyalwa (Diacria) vendryesiana, Guppy. 
Tho land and fresh water Mollusca of those:beds stand out strong and 
Clear, thanks first to the admirable studies of Simpson. He enumerates 
» Proc. U. S. Nat. Mus., Vol. XIX. pp. 303-381, Washington, 1896, 
I have heard that G. F. Harris, British Museum, is now working on one. 
Proc. U. S, Nat. Mus., Vol. XIX. p. 304, Washington, 1890. 
Distribution of the Land and Fresh Water Mollusks of the West Indian Region 
a : 
nd their Evidence with Regard to Past Changes of Land and Sea. By Charles 
“rey Simpson, Proc. U. S. Nat. Mus., Vol. XVII. pp. 423-450, Washington, 1894. 
4 
