DECEMBER, 1903. MAMMALS ELLIOT. 251 



Color: Type $. Above russet, darkest on the rump, the plumbe- 

 ous under fur showing occasionally in places; sides dark russet; spots 

 behind ear, superciliary stripe, face in front of eye, nose, entire under 

 parts, stripe across thigh, and feet pure white; inner side of thighs 

 deep russet like the rump; black bar across rump; tail bushy on apical 

 third, with dorsal and ventral stripe pale russet; sides white; ears 

 russet. Other specimens from Furnace Creek have the tail a purplish 

 drab on the dorsal and ventral stripes, and also the bushy portion or 

 pencil ; but all the examples have the broad, long nasals and other 

 characters of the skull mentioned above. 



Measurements: Type, total length, 240; tail, 142; hind foot 37.5 ; 

 ear, 14. Extremes: total length, 240-260; tail, 142-160; hind foot, 

 37.5-40; ear, 12-15. Skull: total length, anterior end of nasals to 

 outer margin of mastoid, 36; Hensel, 22; greatest width across mas- 

 toids, 22; least interorbital width, 13; width of interparietal at mas- 

 toids, 17; length of nasals, 13; posterior width, 2; anterior width, 3; 

 length of upper tooth row, 3.5; height at coronoid process from 

 angle, 6. 



This Kangaroo rat is probably nearest to D. m. simiolus, but is of 

 a deeper color, and has a differently colored tail and much longer 

 nasals. It appears to be restricted to the Death Valley region. 



PEROGNATHUS. 

 Perognathus *mesembrinus. Sp. nov. 



Type locality: Palm Springs. 



Gen/, char.: Color pale; tail hairy; pencil large, bushy; size 

 medium. 



Color: Upper parts mixed drab gray [and buff; no lateral line; 

 thighs like back ; lips, entire under parts, fore legs, fore and hind feet 

 white; tail above and pencil brownish drab, beneath whitish; ears 

 dark brown, bases covered with tufts of drab gray. 



Measurements: Total length, 195; tail vertebrae, 114; hind foot, 

 23; ear, n. Skull: total length, 21; Hensel, 18; zygomatic width, 

 13; interorbital constriction, 7; mastoid width, 14; greatest parietal 

 width, 10.5; length of mastoids, 9: palatal length, 10; length of 

 nasals, 9.4; length of upper tooth row, 4; length of mandible, 12.5; 

 length of lower tooth row, 3.5. 



This is a small pale desert form nearest allied probably to P. 

 formosus from Death Valley. The skull, while considerably shorter 

 than that of the species just named, is equally broad, and with the 



* fieffefJLjSpwoff South or southern, southern representative of P. formosus. 



