196 MARSUPIALIA. 
and-white varied; tail black at the base, white towards the tip. Length 
about 17”, of tail 12”. 
3. D. quica. Fur soft, with no stiff hairs; dark ashy grey above, yellowish rufous 
beneath ; over each eye a white spot; ears and tail dark, the latter furred for 
about two inches at its base, white towards the tip. Length about 12”, of 
tail 11”. 
B. Pouch rudimentary. 
4. D. cinerea. Fur short, close, yellowish grey above, white or yellowish white 
beneath, the eyes bordered with black ; tail furred for nearly two inches, dusky 
near the base, white for distal half. Length about 8”, of tail 10”. 
5. D. derbiana. Fur rather long, bright rufous above, with a short grey dorsal 
stripe; forehead with a dusky median stripe; lower parts greyish white ; 
ears pink; tail furred for one third of its length, the naked portion pink, 
mottled with brown. Length about 13”, of tail 17". 
6. D. murina. Fur short, bright rufous on the back, greyish rufous on the flanks, 
yellowish white beneath ; eyes bordered with black ; tail furred for only about 
half an inch, the naked portion yellowish brown. Length from 5" to 6”, of 
tail from 6” to 8”. 
1. Didelphys virginiana’. 
Didelphis virginiana, Kerr, Linn. An. Kingd. p. 198 (1792, ex Pennant)’; Baird, N.-Am. Mamm. 
p. 232’. | 
Didelphys californica, Bennett, P. Z. S. 1833, p. 40 (descr. orig.)*; Baird, N.-Am. Mamm. p. 232°; 
Tomes, P.Z. 8. 1861, p. 287°; Dugés, La Nat. i. p. 138°. . 
Didelphys breviceps, Bennett, P. Z.S. 1833, p. 40 (descr. orig.)’. 
Tlacuatzin, Hernandez, Rer. Med. Nov. Hisp. p. 880; De Quad. Nov. Hisp. fol. 3, cap. v. 
Tlacuache of Mexicans. 
Hab. Norta America, from the Hudson River southwards.—Mexico (Uhde, Deppe, 
Mus. Berol.; Liebmann, Mus. Hafn.; Verreaux, Mus. Brit.), Guanajuato (Dugés *), 
Yucatan (Gaumer, Mus. Boucard); GUatEMALA, Coban, Duefias (Salvin, Mus. Brit.®). 
The Opossums of Mexico and California have been believed to differ from those of 
the United States, and have consequently been separated under the respective names of 
Didelphys californica* and D. breviceps’. Of these the former has been recognized by 
Professor Baird and other writers as a valid species, specially distinguishable by the 
* T have here adopted the earliest name which can be clearly and certainly identified with this species. 
Linneus’s D. marsupialis (Syst. Nat. i. p. 71) is evidently founded on a confusion of the North-American 
Opossum with some of the South-American forms, probably D. crancrivora, Gmelin ; and the same remark applies 
to descriptions of his earlier followers. In such a case it seems advisable to relinquish the uncertain title 
altogether. 
