134 bulletin: museum of comparative zoology. 



Nesophontes micrus G. M. Allen. 

 Plate 1, fig. 7-10. 



Nesophontes micrus G. M."*Allen, Bull. M. C. Z., 1917, 61, p. 5, pi., fig. 14. 



The only specimen previously available was the type, a fragment 

 of the right lower jaw, containing a part of jmu, mi, vio, and the roots 

 of Ws. It was referred to Nesophontes with some doubt, but the large 

 number of specimens now at hand proves that it was correctly assigned 

 to that genus. In addition to several nearly complete crania and 

 lower jaws, sundry limb-bones, chiefly femora, were also collected, so 

 that a detailed comparison may now be made between this and the 

 Porto Rican species, N. edithae Anthony. As in that species, the 

 specimens fall into two series, a larger and a smaller, which as Anthony 

 (1916) has suggested, probably represent males and females respec- 

 tively. The differences are slight but constant, and can hardly mean 

 anything else, though it is unusual among the Insectivora to find 

 sexual dimorphism in size. The skulls assumed to be those of males 

 have the rostrum broader and stouter, less tapering, with slightly 

 broader palates and parallel instead of convergent tooth-rows; they 

 are slightly larger also in general dimensions. Anthony's description 

 of the skull of N. cdithac applies in general to N. micrus. In one speci- 

 men of the latter, the pterygoids are intact and are seen to project 

 ventrally below the level of the palate for about a millimeter, then 

 curve posteriorly to end each in a delicate bony hook. The teeth 

 seem essentially alike in both species, though in none of the skulls of 

 the Cuban animal are the three incisors present. The double-rooted 

 canine (Plate 1, fig. 9) is relatively large, with a deep groove on its 

 anterior face, two similar grooves delimiting a median ridge on the 

 inner face of the tooth, and a slight cingulum on the postero-external 

 half. Anthony states that the paracone is absent in the molars of 

 Nesophontes, but this is not the case except in much worn specimens. 

 Those with unworn molars exhibit the typical W-pattern, except that 

 the paracone is much reduced in size, hardly one fourth as large as the 

 metacone. The hypocone is represented by a cingulum-like ledge. 

 As previously pointed out, the third lower molar in A", micrus is rela- 

 tively smaller than in N. edithae; the second lower premolar is also 

 much smaller than the first, instead of being nearly the same size. 

 In lower jaws presumed to be of females the ramus is much the more 



