ALLEN: FOSSIL MAMMALS FROM CUBA. 147 



altogether superficially — actually exposed on the surface — in caves. 

 This may indicate that it was kept for food by the natives and carried 

 from one island to another, for neither Dr. Boaz, nor Mr. Peters and 

 myself found its bones in deeper excavations that produced the ground 

 sloth, Acratocnus, Heteropsomys, Heptaxodon, or Elasmodontomj^s. 

 The complete identity of Isolobodon remains from Santo Domingo 

 with those from Porto Rico, as shown by Miller, is further indication 

 of some such equalizing factor. Nothing corresponding to Boromys 

 has been discovered in Porto Rico, though Brotomys of Santo Domingo 

 is probably related. Of other Porto Rican genera, Elasmodontomys, 

 Heteropsomys, Homopsomys, and Heptaxodon, nothing has as yet 

 appeared in the islands to the west. 



Contrary, then, to what one might perhaps expect, the present 

 evidence shows that Porto Rico, the Greater Antillean island most 

 distant from the North American continent but nearest the South 

 American end of the chain, contained the most varied fauna of 

 terrestrial mammals as well as the largest forms (except for Mega- 

 lochnus). For Elasmodontomys was bigger than the common porcu- 

 pine, Heteropsomys was as large as an agouti; while Amblyrhiza, 

 of Anguilla, was nearly the size of a paca. These facts suggest that 

 the land-mammals of Cuba are farther distant than those of Porto 

 Rico from some center of distribution and reached there, not by way 

 of Central America, but from South America by way of the supposed 

 former land-mass of which the Lesser Antilles now form the remnant. 

 The fact that Procapromys, the nearest living continental relative of 

 Geocapromys and Caproniys, is to be found so far as yet known, only 

 in the mountains of Venezuela, between La Guayra and Caracas, 

 possibly points in the same direction. Further exploration alone, 

 however, may hope to solve the matter. 



The comparison with Santo Domingo merely accentuates the known 

 peculiarity of its fauna, for with the exception of Solenodon, generically 

 identical with the Cuban form, its few other genera hitherto known 

 are not seen on the other islands, namely, Brotomys, Plagiodontia, 

 and (if it be endemic there) Isolobodon. 



