Western Mexico and Lower California. 45 



This pretty little mouse is quite different from any North - 

 American species known to me. Its relationship appears on 

 the whole to be with the P. aztecus group, of which it may 

 be a diminutive peninsular representative *. Its small size, 

 rufous colour, and long, thinly haired, and almost unicolor 

 tail separate it widely from any Californian species hitherto 

 described. 



Peromyscus leucopus Goolidgei^ subsp. n. 



One of the pallid forms of this species. General colour 

 above exactly matching that of specimens from Loveland, 

 Colorado, assigned by Mr. G. S. Miller, their donor, to 

 P. I. nehrascensis , Mearns ; therefore by no means corre- 

 sponding to the description of P. I. Thurherij Allen f, from 

 the San Pedro Martir Range, which is said to be " strongly 

 varied with black, the prevailing tint being often decidedly 

 blackish." Anterior part of outer surface of ear scarcely 

 darker than back. Under surface sharply defined white, the 

 slaty bases of the hairs showing through. Posterior part of 

 sole and tail rather thinly haired for this group, the latter 

 scarcely pencilled, its dorsal surface brown, the scales showing 

 through ; very different to the heavily haired and pencilled 

 tail with black dorsal surface of yiehrascensis. 



Dimensions of the type (an adult female, measured in the 

 flesh) :— 



Head and body 91 millim. ; tail 76; hind foot^ with claws, 

 22 ; ear 20. 



Skull (imperfect behind) : basilar length (c.) 19*5 % j 

 greatest breadth 13; length of nasals 95; diastema 6'6; 

 length of upper molar series 3" 7. 



Hah. Santa Anita, Cape Region of Lower California. 

 Coll. D. Coolidge. 



Type collected May 21, 1896. Original number 54. 

 Four specimens examined. 



Lepus californicus Xanti, subsp. n. 



Similar to the typical form in most respects, but distin- 

 guished by its greyer ears and smaller size. General colour 

 almost exactly as in pale examples of iypicus, except that the 

 cinnamon tinging of the belly is stronger. Ears greyer, with 

 less suffusion of buffy or yellowish, the hairs on the inner 



* Specimens of it were referred by Dr. Coues to P. aztecus in his 

 monograph (Mon. N. Am. Eod. pp. 101, 102), but at that date no Mexican 

 specimens were available for comparison. 



t Bull. Am. Mus. N. H. v. p. 1^6 (1893). 



j In a perfect specimen this dimension is 19*(3. 



