1 68 Bulletin American Museum of Natural History. [Vol. XIV, 



Hidalgo : Pachuca, 2, and 3 additional skulls ; Rio del Monte, i ; Ixmi- 

 quilpan, i ; Tulancingo, I, young ; all the adults are in gray phase. 

 Mexico : Tlalpan, 3 ; Ameca, i ; Salazar, i ; all in gray phase. 

 Morelos : Yautepic, i, gray. 

 Puebla : Atlixco, 2 ; Metlaltoyuca, 2 ; Chalchicomula, i ; Huanchinango, 



1 ; San Marten, i (and i additional skull) ; all in gray phase. 



Vera Cruz : Jico, i, black ; Las Vegas, i, gray ; Maltrata, i ; Minatitlan, 



2 ; Orizaba, 2, gray, and 2 additional skulls. 



Guerrero : Acapulco, 6 4 black, i gray, and i pure albino. 



Oaxaca : Tuxtepec, 2 gray, 2 very young, and an additional skull ; Cuicatlan, 

 I, gray ; Oaxaca, i, gray ; Reyes, 3 gray, and I skull ; San Domingo, i, black ; 

 Tehuantepec, 2 i black, the other gray. 



Total, 106 skins, 22 additional skulls, and 29 young in alcohol. 



Geographical Distribution. The northern limit of the range of 

 the D. marsupialis (= californica auct.) group begins on the coast 

 of Texas near Nueces Bay, and doubtless occupies the coast 

 region thence southward to Guatemala, and the interior table- 

 lands across Central Mexico to the Pacific Coast, ranging on the 

 west coast from the southern part of Sinaloa to Guatemala. The 

 northern limit of its range in Mexico has not been definitely as- 

 certained, but there are no specimens in the present collection 

 from the northern tier of States, except from near their southern 

 border. The most northerly points represented are Monterey, in 

 Nuevo Leon; Hermosillo, in central western Sonora; and Sierra 

 de Choix in the extreme northern part of Sinaloa. There is no 

 record of the occurrence of any form of Opossum along the 

 southern border of the United States west of Texas, the early 

 vague references to the occurrence of D. californica in California 

 being unsupported by modern research. 



The number of specimens of this group at present available for 

 study is about 220. Large portions of Mexico that are doubtless 

 inhabited by this animal are entirely, or almost entirely, unrepre- 

 sented, as, for example, the State of Tamaulipas, from which there 

 are only a few specimens, from the vicinity of Tampico. Nuevo 

 Leon is represented by only four specimens, from Monterey. 

 There are none from Coahuila. Chihuahua is represented by a 

 single specimen from near Batopilas, and Sonora by a single 

 specimen from Hermosillo. The specimens from Sinaloa are all 

 but one from near the coast of the southern portion. Several of 

 the interior States also are practically unrepresented, as San Luis 



