190 BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



These were presented to the United States National Museum by 

 the Carnegie Institution. 



Besides having studied the material indicated, I have twice been 

 able to examine all of Duncan's types preserved in the Museum of the 

 Geological Society of London and in the British Museum (Natural 

 History), and I heartily thank the officers of those institutions for 

 the privileges accorded me. In 1904 Prof. A. G. Hogbom and 

 Prof. C. Wiman most generously permitted the Cleve collection 

 from St. Bartholomew and Anguilla to be sent to me in Washington. 

 This collection contained aU of Duncan's types from St. Bar- 

 tholomew; and I thank Messrs. Hogbom and Wiman for the excellent, 

 opportunity they gave me. Some duphcates from the Cleve col- 

 lection, identified by direct comparison with Duncan's types, were 

 procured for the United States National Museum by exchange. 



Opportunities to study the Gabb collection from Santo Domingo, 

 divided between the Philadelphia Academy of Natural Sciences and 

 the Museum of Comparative Zoology, and the specimen obtained by 

 Miss Carlotta J. Maury in Santo Domingo, have been very valuable. 

 In fact, as a result of Miss Maury's careful stratigraphic studies in 

 that RepubHc, the stratigraphic relations of the Santo Domingan 

 faunas became known. Except retaining a few duphcates, she has 

 generously presented to the United States National Museum the 

 material obtained by her. 



I wish to thank my associates in the United States National Museum 

 and in the United States Geological Survey for their helpfulness 

 during the prosecution of this study. Mr. W. O. Hazard, of the 

 Survey photographic laboratory, made most of the photographs used 

 for illustrations, and Miss Frances Wiesser retouched some of them. 



There is almost no Hterature on the Tertiary fossil corals of 

 Central America, Cuba, or Porto Kico. I hsted a few Pleistocene 

 species obtained by Mr. R. T. Hill at a place IJ miles west of Port 

 Limon, Costa Rica; ^ and FeUx has recorded from Colombia ^ three 

 species, as follows : 



OrhiceTla theresiana FeHx, probably a synonym of Solenastrea 

 hournoni M. Edward and Haime. 



Isastraea turhinata Duncan. 



Steplianocoenia cf . S. jairbanksi Vaughan. 



None of these records is further considered in the present paper. 



Toula has described Oculina gatunensis from Gatun (see footnote, 

 page 352 of this paper). 



GEOLOGIC CORRELATION BY MEANS OF FOSSIL CORALS. 

 That vegetative variation in corals is great and that without large 

 suites of specimens the Hmits of variation can not be ascertained are 



» Mus. Comp. Zool. Bull., vol. 2S, p. 275, 1S98. 



* FeUx, J., Ueber einige fossile Korallen aus Columbien, K, Bayer. Akad. Wiss.,math.-phys. Kl.. 

 Sitzungsber., vol. 35, pp. 85-93, 1905. 



