FOSSIL VERTEBRATES IN THE WEST INDIES. 163 



The Porto Rico Discoveries. 



With these and other considerations in mind, the New York 

 Academy of Sciences decided in 191 3 to undertake a systematic 

 survey of the geology and natural history of Porto Rico, in coopera- 

 tion with the local government and with the American Museum of 

 Natural History. This was very ably conducted under direction of 

 Dr. Britton. The geology was quite thoroughly investigated by 

 Drs. Berkey, Reeds and others and the reports afford a better 

 knowledge and understanding of the geologic history of this island 

 than we have of any of the others. The marine limestone yielded 

 one interesting fossil mammal, a sirenian or sea-cow allied not to 

 the manatees as one would expect, but to the old-world dugongs. 



The most important find in the way of land animals was made 

 in the course of investigations in a cave near Utuado, where human 

 remains probably prehistoric were unearthed, and beneath them re- 

 mains of several kinds of extinct mammals. This stimulated further 

 search of the numerous caves in the island, undertaken by Mr. 

 Anthony for the American Museum of Natural History, and the 

 results of his very successful work have been published in a well- 

 illustrated memoir issued last December. 



The fossil mammals include one insectivore, one edentate and a 

 number of rodents, all new and very peculiar types, widely different 

 from any known animals ; also a number of bats closely allied to the 

 living bats still on the island. jMost of this fauna is represented by 

 well-preserved skulls and various bones of the skeleton. 



The insectivore Ncsophontcs is so distinct that it has to be placed 

 in a family by itself. It has some distant affinities with the Sori- 

 coidea (moles and shrews), but is a very primitive type, and its 

 nearest allies are perhaps to be found among the Eocene insectivora 

 of North America. There is no suggestion of relationship to Sole- 

 nodon, the only other known insectivore of the West Indies, nor to 

 the extinct Necrolcstes of South America, the only insectivore 

 belonging to that continent. Like the Eocene insectivores it retains a 

 great deal of the primitive tri-tubercular type of dentition which 

 nearly all — if not all — the primitive mammals once possessed. 



The edentate, Acratocnus, is not less interesting. The skull is 

 superficially much like the two-toed tree sloth Choloepus, with the 



