NORTH AMERICA AND THE WEST INDIES 101 



Remains of these two supposed spiny rats differ chiefly in 

 size, and both occur together in cave deposits; hence they may 

 be considered under a common grouping. The genus is related 

 to Brotomys of Hispaniola, but the skulls differ in that the 

 latter shows no external swelling of the bone over the posterior 

 termination of the root of the upper incisor, nor is there a 

 definitely marked channel for the passage of the fifth nerve on 

 the floor of the antorbital foramen; in Boromys, on the other 

 hand, the posterior termination of the incisor root is marked 

 by an obvious external swelling, and the floor of the antorbital 

 canal is provided with a groove for the nerve. 



So far as known from parts of the skeleton, the two species 

 were alike in structure. There were four cheek teeth in each of 

 the tooth rows. Each tooth had a deep inner and outer re- 

 entrant of enamel extending to the center of the tooth, the 

 inner slightly in advance of the outer in each jaw. A smaller 

 reentrant of less vertical depth was present in both the anterior 

 and the posterior halves of the premolar and in the posterior 

 half only of the three molars, penetrating from the outer side. 

 With wear these smaller inlets are soon cut off and appear as 

 little circular islands of enamel in the center of their respective 

 sections and with still further wearing down, disappear. The 

 enamel wall at this stage has nearly the outline of a figure 8. 

 The alveoli of the molars are squarish in outline with shallow 

 cavities for short roots. The incisors were orange-yellow in 

 color. In the larger species, B. offella, the alveoli of the upper 

 teeth have a combined length of 11.5 mm., against 7.6 mm. in 

 the smaller animal, B. torrei; while the crown area of a single 

 molar in the former is about three times that in the latter. 



In former times both these species seem to have been well 

 distributed not only in Cuba, but in the Isle of Pines as well. 

 The larger animal was first discovered in excavations of an old 

 village site at Maisi, Baracoa; hence it was probably used as a 

 food animal by the Indians. Shortly after this discovery, a 

 number of maxillae and mandibles were found in a cave at 

 Limones, Cuba, and in similar situations in the Sierra de 

 Casas, Isle of Pines, by Dr. Thomas Barbour and his associates. 

 These remains may have been brought in by the now extinct 

 giant barn owl. Other but "scanty material" representing the 

 same animal was found at about the same time by Dr. H. E. 

 Anthony (1919) in the course of excavations in caves at 

 Daiquiri, in eastern Cuba, brought in probably by owls. 



