154 BULLETIN 56, UNITED STATES NATIONAL MUSEUM. 



of the ventral surface. The sides of the neck are sometimes strongly 

 linked with buff. There is also a slight extension forward on the 

 top of the head of the general dusky color of the dorsal surface, which 

 usually forms a V-shaped area, extending to a point midway between 

 the ears and eyes. It is indistinct in outline and varies greatly in 

 intensity and extent in different individuals, being often absent, the 

 head then being practically pure white. Eyes with a very narrow 

 blackish eye ring, widening anteriorly into a small, usually indistinct. 

 preocular spot, sometimes nearly as large as the eye, but often obso- 

 lete. Fore and hind limbs black. (•/. .1. Alien.) 



Cranial and dental characters. — Posterior border of nasals forming 

 i V-shaped point. (See table of cranial measurements, p. 155.) 



Remarks. — We obtained no evidence of the presence of this north- 

 ern species nearer the International Line than the region surround- 

 ing San Antonio, Texas, where it is said to outnumber Didelphis 

 mesamericana texensis. 



