APR. 1903. NEW SPECIES AND SUBSPECIES OF MAMMALS ELLIOT. 169 



Perognathus *.knekus. Sp. nov. 



Type locality. Rosarito, San Pedro Martir mountains, Lower 

 California, Mexico. 



Gen. char. Size very large; color beneath deep cream buff. 

 Skull large with very long slender nasals broadening at tip. 



Color. Upper parts ochraceous buff lined with black; top of 

 nose and whiskers blackish; spot in front of eye and broad lateral 

 band from lip to posterior part of thigh ochraceous buff; sides 

 . above lateral line grayish buff; a pure white spot, the hairs white 

 to the roots, on chest between arms and extending in a narrow 

 line towards abdomen; rest of under parts, arms, legs, hands and 

 feet dark creamy buff; tail hairy, above blackish, beneath cream 

 buff; ears dark brown. 



Measurements. Total length, 228; tail vertebrae, 126; hind 

 foot, 28; ear, 9.5. Skull: occipito-nasal length, 32; Hensel, 22; 

 zygomatic width, 16.5; greatest mastoid breadth, 16; greatest 

 width of interparietal, 8; interorbital constriction, 7: median 

 length of nasals, 13; lateral length of nasals, 14; posterior 

 width of nasals, 2; anterior width of nasals, 3: greatest width of 

 rostrum, 5; palatal length, 13; length of tooth row, alveolar 

 border, 4; length of mandible, tip of angle to alveolus of 

 incisor, 14.2. 



I hesitated for a time to describe this pocket mouse, thinking 

 that perhaps its very unusual color might be attributed to the soil; 

 but on examination the hairs of the under parts were found to be 

 of a uniform hue to the roots, and in the midst of the buff was 

 the conspicuous white spot, the hairs of which were also white 

 to the roots. If the under parts were stained by the soil it is 

 difficult to understand why the white spot was left when all around 

 it was a uniform buff or cream buff. Other specimens of the 

 genus, but evidently not of this species, were taken at Rosarito, 

 having the under parts all pure white, so the soil had not affected 

 them. In a letter just received from Mr. Heller writing of this 

 specimen, he says, "I believe the under parts are not stained." 

 Beside its peculiar coloring, it seems to be among the largest 

 members of the genus, even exceeding in the general measurements 

 of body or skull baileyi, b. rudinoris and zaccatecus. Only the type 

 specimen was obtained. 



?, buff color. 



