180 J. D. Dana — Origin of Coral Reefs and Islands. 



of the Gulf to that of the Pacific waters prove that it continued 

 to be a salt-water gulf through the era of elevation. 



Mr. Agassiz infers that the connection of the West India 

 Islands with South America existed before the Quaternary era. 

 But there are other facts which seem to prove that it was con- 

 tinued into, or at least was a fact, in the Quaternary. 



The opinion as to a connection of the Windward Islands 

 with South America in the Quaternary was presented by Prof. 

 E. D. Cope in 1868, and earlier, as he states, by Pomel, on the 

 ground of the discovery in the caves of Anguilla of a species 

 of gigantic Rodent related to the Chinchilla, as large as the 

 Virginia deer, and nearly equaling the Quaternary Castoroides 

 of Ohio.* Farther, De Castro, as cited by Dr. J. Leidy in his 

 " Mammalian Fauna of Dakota and Nebraska," 1869, an- 

 nounced, in 1865, a gigantic sloth of the "Quaternary," from 

 Cuba, which he referred to the genus Megalonyx, and Dr. Leidy 

 named Megalocnus rodens, proving a Quaternary connection be- 

 tween the continent and Cuba. 



The fact of an elevated condition of the region sufficient to 

 make Cuba and Anguilla part of the continent during the 

 earlier Quaternary, if not in the Pliocene also, is thus made quite 

 certain. This is fully recognized by Wallace, f Such a condi- 

 tion could hardly have existed without a large elevation also 

 of Florida, though probably not, as Mr. Agassiz holds, to the 

 full amount of the depression between it and Cuba — nearly 

 3000 feet — because Cuba is most closely related in fauna to 

 South America. The subsidence which brought the region 

 to the present level was consequently within the coral-reef 

 period. It is hence hardly to be doubted that the making 

 of the Florida, Bahama and other West India coral reefs was 

 going on during the progress of a great subsidence. None of 

 the facts mentioned by observers are opposed to this view. 



It is of interest to note here that on Cuba and Jamaica there 

 are elevated coral reefs, the highest on Cuba 1000 feet above the 

 sea, according to Mr. Agassiz, and probably at one point 2000, 

 according to Mr. W. O. Crosby's observations,^; and on Ja- 

 maica 2000 feet, according to Mr. Sawkins ; indicating that 

 there have been upward movements subsequent to the down- 



*Proc. Philad. Acad. Nat. Sci., 1868, 313. and Proc. Philad. Amer. Phil. Soc., 

 1869, 183 ; also Smithsonian Contributions to Knowledge, 30 pp. 4io with 5 plates, 

 Washington, 1883. The last paper (prepared in 1878) contains descriptions of 

 the following species from the Anguilla bone-cave. Amblyrhiza inundata Oope 

 (the large Rodent announced in 1869), A. quadrans Cope, A. latidens Cope, an 

 Artiodactyl apparently of the Bovidce and a little smaller than Ovis aries. With 

 them was obtained an implement (" a spoon-shaped scraper or chisel ") made of 

 the lip of the large Strombus gigas. 



+ Geograph. Distrib. of Animals, ii, 60, 78. 



X Proc. Boston Soc. Nat. Hist, sxii, 124, 1882, and in abstract in this Jour, 

 xsvi, 148, 1883. 



