-13- 
Si 
Poriies anguillansis Vaughan 
•Poriies sp. Anguilla 
Stylophora aluaensis Vaughan ? Alum Bluff, Fla. 
Btylophora anguillensis Vaughan 
Porto Rico. 
Th@ following account of the geologic succession in Porto Rico 
1/ 
is compiled fro© the publications of R. T. Hill. 
1 / Notes on the forest conditions of Porto Rico? U. S. Dept. Agriculture 
Div, of Forestry Bull. No. 25, pp. 14, 15, 1899. 
The geology and physical geography of Jamaica; Bull. Mus. Comp* Zool. 
vol. xxxlv, Appendix I, p. 225, 1899. 
The description of the section in ascending order is as follow®: 
(l) An older plexus of water-sorted hornblendic volcanic material, 
C c. 
tuffs and conglomerates with interbedded Cretaceous Rudistsan limestone 
similar to that of Jamaica, composing the central mountains. 
There are two limestone formations, both of small area, interbedded 
in the mass of volcanic rock. One of these, found os the crest of the 
island near C&yey and Aiboniie, is a black, bituminous, shaly limestone 
interbedded with volcanic conglomerate. This calcareous horizon, fully 
1,000 f8et thick, apparently forms the crsst of the sierra and weather® 
into soils noted as the best tobacco lands on the island. The other is 
a light gray crystalline limestone with Cretaceous fossils (Rudistes). 
It outcrop® on an east and west line from near Cabo Rojo to 15 kilo- 
meters north of Ponce on the Adjuntas road. 
