ALLEN: FOSSIL MAMMALS FROM CUBA. 135 



slender, while in those assumed to represent the males, it is larger and 

 more heavily proportioned with a greater downward curvature of the 

 lower border of the ramus. 



The following measurements illustrate the sexual difference in size 

 of the skull : — 



While agreeing with Anthony (1916) that the characters distinguish- 

 ing this genus from other insectivores with which sufficient comparison 

 can be made, are enough to give it rank as the representative of a 

 separate family, I am unable to share his view that they ally it " more 

 closely to the Soricidae than to other families." The fundamental 

 resemblances to the zalambdodonts seem more striking^ It is natural 

 to make comparison with Solenodon, the other insectivorous genus 

 that has been contemporary in the Greater Antilles with Nesophontes. 

 The general points of liken '^ss are obvious : — the shape of the skull, 

 the incomplete zygomatic arch, the long tubular rostrum, early fusion 

 of the nasals (also in Soricidae), the slight inflation of the frontal 

 region, large foramen magnum, prominent lambdoid, and low sagittal 

 crests, the tooth-formula, the double-rooted upper canine, and the 

 transversely expanded mandibular condyle. One specimen of Neso- 

 phontes has preserved the petrous bone of the ear, though the tym- 

 panic, which therefore is separate, has gone. The petrosum is very 

 similar in general topography to that of Solenodon. On the other 

 hand Nesophontes does not show the specialization of incisors nor the 

 reduction of the canines, so marked in Solenodon. The latter, how- 

 ever, is rather an extreme type in this respect as compared with 

 Microgale or Oryzoryctes, in which the canine is little reduced and 

 the incisors have merely an additional posterobasal cusp. The milk 

 incisors of Solenodon are small unspecialized teeth, the first pair in 

 no way resembling their enormous permanent successors. A com- 

 parison of the upper molars is of great interest. In Solenodon as 



