120 EXTINCT AND VANISHING MAMMALS 



very different. The upper tooth rows converge strongly 

 forward instead of being nearly parallel, while the pattern of 

 the enamel folding is simpler. Each of the upper molars has 

 a shallow outer and a much deeper inner reentrant loop, the 

 latter of which extends inward and forward, diagonally, to 

 touch the smaller outer one. The first tooth of the four, the 

 premolar, has in addition a second small outer reentrant in 

 advance of the one that meets the inner loop. In the lower 

 tooth row there are two shallow reentrants of enamel on the 

 inner side of each molar, the posterior of which meets the 

 single outer reentrant nearly at the center of the tooth. In 

 Plagiodontia the inner reentrant is much deeper, runs more 

 diagonally forward, and does not meet the smaller fold of the 

 outer side. The teeth of young animals have the same pattern 

 as do those of adults, for they are continuously growing; but 

 the size of the individual teeth increases with age and wear. 



This must have been a common species on Puerto Rico up 

 till the period of white occupation. Both Dr. H. E. Anthony 

 and I found its bones on the surface in undisturbed caves on 

 the island, and they are abundant in kitchen middens, mingled 

 with broken pottery and ashes, indicating that they formed a 

 staple article of diet for the Indian aborigines. Shortly after 

 the discovery of its bones in cave deposits probably of human 

 origin in Puerto Rico, Miller (1916b) announced the finding of 

 additional jaws and other parts of the skeleton in the course of 

 excavating Indian sites at Macoris and San Lorenzo, in the 

 Dominican Republic. He was unable, however, to distinguish 

 these remains from those found on Puerto Rico. Again, in a 

 later paper he (Miller, 1918a), reports the discovery of many 

 other bones of this hutia, secured by Theodoor de Booy in the 

 course of excavating two Indian sites in the Virgin Islands, one 

 at Magens Bay, St. Thomas, the other at Salt River, St. Croix. 

 The wide distribution of the species Puerto Rico, Hispaniola, 

 and the Virgin Islands the complete lack of differentiation on 

 these three areas, and finally the frequent occurrence of the 

 remains in deposits of human origin, all point to the fact that 

 it was a regular source of food for the aborigines and that they 

 carried it about by canoe from island to island, to serve their 

 needs. Whether its original home was on Puerto Rico or on 

 Hispaniola must remain uncertain, but Anthony (1918) in- 

 clines to the view that judged from its apparently wide distribu- 



