610 BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



to South America. Miller has recently published an important paper 

 on this subject, 1 and states: "With the characters of so many [eight] 

 genera known it becomes possible to gain some idea of the Antillean 

 hystricine fauna. 2 The most noticeable feature of these genera 

 considered as a group is their similarity to the Santa Cruzian and 

 Entrerian rodents which Ameghino and Scott have described and 

 figured. In no instance has the same genus been found in both 

 the West Indies and Argentina or Patagonia; but the Antillean 

 rodents thus far discovered never show such peculiarities that their 

 remains would appear out of place among those of their extinct 

 southern relatives, while as a whole they would at once be recognized 

 as foreign to the present South American fauna." 



On the following page of the same paper he says: "So far as can 

 be judged from eight very distinct genera the Antillean hystricine 

 rodents do not present the characters that would be expected in 

 animals derived from South America during any period geologically 

 recent. Neither have they the appearance of an assemblage brought 

 together at different times by migration or chance introduction. 

 On the contrary they suggest direct descent from such a part of the 

 general South American fauna, probably not less ancient than that 

 of the Miocene, as might have been isolated by a splitting off of the 

 archipelago from the mainland. Of later influence from the conti- 

 nent there is no trace." 



The mammals furnish more evidence of this kind than I am pre- 

 senting here, and Barbour and Stejneger, from their study of rep- 

 tiles, have reached the same conclusions. These conclusions accord 

 with the tectonic history of the region, namely, that in late Tertiary, 

 probably Pliocene time, the West Indian Islands as we know them 

 were produced by block-faulting which broke into pieces a far more 

 extensive land area. Although I greatly respect the scholarship and 

 appreciate the valuable researches of Dr. W. D. Matthew, I am unable 

 to agree with his opinions as to the means of distribution of West 

 Indian mammals and some of the other land vertebrates. 



According to Hill, the volcanoes of the Windward Islands date 

 back at least to the Eocene. He says: "After the Miocene, vul- 

 canism became quiescent in the Great Antilles and the Coastal Plain 

 of Texas, but has continued to the present in the four great foci of 

 present activity — southern Mexico, the northern Andes, Central 

 America, and the Windward Islands. In the last two regions men- 

 tioned, the greater masses of the present volcanic heights were piled 



1 Miller, Gerrit S., Jr., Bones of mammals l'rom Indian sites in Cuba and Santo Domingo, Smithsonian 

 Misc. Coll., vol. 66, No. 12, 10 pp., 1 pi., ISIS. 



2 Idem., p. 3. 



