OF SANTO l^OMINGO. 



97 



greater part of the fossiliferous strata, iiiclnding all the Santo Domingo beds in the 

 Miocene Tertiary. 



Shortly after the appearance of the joint paper by Moore and Sowerby, Mr. Conrad 

 published a short note,* having more particular reference to the Yicksbnrg deposit in 

 Mississippi, asserting that he found an " analog}^," and even adding " whether all the 

 forms in this gi'oup in St. Domingo are synchronous remains to be proved, but the 

 probability is that they are." He claimed to have identified three species as occurring 

 in the two regions ; his determinations being based on Sowerby's figures. My own 

 camparison of specimens completely disproves even this. There is not more than the 

 ordinary generic resemblance. But I have found- a single species in common — his 

 Ficus Mississiijpiensis. Even were there a dozen it would be poor proof of synchro- 

 nism. He explained the small numbei- of common species by the geographical 

 dissimilarity. 



But still later he repeats the assertion of the Eocene Oligocene ") age of the 

 Santo Domingo beds in such a categorical manner as to demand an equall}^ pointed 

 refutation,f the more esjjecially since Mr. Com-ad is the oldest and best informed of 

 the authorities on the American Tertiaries. 



In view of this expression of opinion being so evidently only a mere guess, I 

 should have disregarded it and have quietly acquiesced in the opinions of my pre- 

 decessors were it not for the numerical richness of the collections I have been able to 

 make, and which have doubled the number of species known to exist in the Dominican, 

 if not in the West Indian Tertiaries. 



In 1849 Mr. Heneken sent his first installment of fossils to London consisting of 

 "fishes' teeth, a crab, 84 species of Mollusca, an echinoderm, 18 species of coral, 

 numerous foraminifera, dicotyledinous wood." The mollusca on being critically 

 examined by Messrs. Moore and Sowerby, and compared with recent and fossil species, 

 gave 13 living species, 2 doubtful, and the remainder extinct ; or a percentage of 17 

 to 19 with a greater resemblance to the European than to the ^N'orth American 

 Miocene. The other remains also corroborated this result at the same time. " Mr. 

 Sowerby was much struck with the resemblance of many of the shells to recent species 

 inhabiting the seas of China, Australia and even the western coast of America." In 

 1853 Mr. Heneken added another collection to the first which raised the number of 

 known species to 163 mollusca, of which 127 were gasteropods, and 36 bivalves. 



* Pi-oc. Pliil. Acad. 1852, p. I'jy. 



t See Smitlisoniaii Check List, Eocene and Oligocene fossils of N. A. (Sm, Misc. Collection, No. 200), p. 37, -where 

 he simply says : "The Oligocene has been fonnd in St. Domingo, &c." 

 A. P. S. VOL. XV. Y. 



