10 Bangs — A New Pigmy Onjzomys from Colomhia. 



although slightly diflerent from that of the 0. dryas group (see Thomas, 

 Ann. and Mag. Nat. Hist., 7th ser., II, 1898, p. 267). 



Color. — Upper parts tawny ochraceous, lined with hrownish black- 

 tipijed hairs, Avhich are most numerous on top of head and on middle of 

 back, but more scattering on rump ; lower sides and upper surface of arms 

 and legs paler and more mixed with buflfy ; under parts white, the hairs 

 pale gray at base on center of belly only, while on throat, neck, and under 

 surface of legs they are white to the base; ears dark brown; feet and 

 hands whitish ; tail very long, nearly naked, dusky above, dull grayish 

 white below. 



Measurements. — The type, i^ adult, total length, 193; tail vertebrae, 115 ; 

 hind foot (with claw), 20; ear from notch, 14. The two largest indi- 

 viduals from San Miguel measure — No. 8223, (^ adult, total length, 200; 

 tail vertebrae, 115; hind foot (with claw), 22; ear from notch, 13; and 

 No. 8225, ? adult, total length, 200 ; tail vertebra?, 115 ; hind foot (with 

 claw), 22; ear from notch, 13. 



Skull, the type, cJ* adult, basal length, 17.6; zygomatic width, 11.6; 

 mastoid width, 9.2; interorbital width, 3.8; length of nasals, 7; length 

 of upper molar series, 3.2; length of mandible, 11.2. 



Remarks. — There is a slight individual variation in color among the ten 

 specimens of 0. naims, due principally to the greater or less number of 

 black-tipped hairs scattered along the back and head — some specimens 

 being more nearlj^ clear tawny ochraceous than the type. 



The species of pigmy Oryzomys form a compact group of closely related 

 forms, many of which may prove only subspecifically distinct from one 

 anotlier, but until their relationships are better understood it seems well 

 to give the new form full sj)ecific rank. 



