DIDELPHYS. 17 



aurita (Didelphys), Alston, Biol. Centr. Amer. Mamm., i, 1881, 



p. 197. (nee Wied.) 

 RICHMOND'S OPOSSUM. Zorro in Costa Rica. 



Type locality. Greytown, Nicaragua. 



Geogr. Distr. Nicaragua and Costa Rica. 



Genl. Char. Base of under fur orange buff; tail long. Skull: 

 long, narrow; nasals long. 



Color. Sides of head to base of ears pale buffy white; median 

 stripe black; black band from ear to whiskers; cheeks buffy white; 

 nape and shoulders black; the long hairs black on anterior part of 

 body, white on posterior part; under fur with black tip, then yellow- 

 ish white, and orange buff at base; under parts buffy, base of hair 

 brownish yellow; legs, hands, and feet black, nails yellowish white; 

 tail black on basal half, remainder flesh color; ears black. 



Measurements. Total length, 948; tail, 477; tarsus, 70. Skull: 

 total length, 114; nasals, 54; zygomatic width, 55; across postorbital 

 processes, 25; interorbital constriction, 11.5; mastoid breadth, 32.5; 

 palatal length, 65; length of upper molar series, 37.4. 



inxulni-ift (Didelphis!), Allen, Bull. Amer. Mus. Nat. 

 Hist., 1902, p. 259. 

 ISLAND OPOSSUM. 



Type locality. Caparo, Island of Trinidad. 



Geogr. Distr. Islands of Dominica, Grenada, and St. Vincent, 

 West Indies. Trinidad. 



Genl. Char. Lighter in color than true D. mesamcricana, and 

 larger in size. 



Color. Head yellowish white to nape, orbital ring brownish; long 

 hairs of top of head tipped with dusky; under fur yellowish white, 

 the coarser hair tipped with blackish ; at base over nape and shoulders 

 brownish ochraceous; long stiff overhair wholly white, or wholly 

 black, or mixed black and white, evidently an individual peculiarity. 

 Under parts yellow or yellowish white, tips of some hairs blackish; 

 arms from elbows and legs from knees, blackish brown; tail naked, 

 proximal third blackish brown, apical two-thirds flesh color or 

 whitish; ears blackish brown. 



Measurements. Total length, 810-955; tail, 425-465; hind foot, 

 55-66; ear, 55-65. Skull: total length, 101-110; basal length, 91-101 ; 

 zygomatic breadth, 61-63.5; postorbital breadth, 21-24; occipital 

 breadth, 30-32; length of nasals, 47-50; breadth at canines, 19-20; 

 upper tooth row, 33-36. 



Ixittiji (Didelphis!), Thomas, Novitat. Zool., ix, 1902, 



