DWARF POCKET RAT 



it carefully for any injury and I suspect that the tail is very 

 important in the balance and locomotion of the Kangaroo Rats, 

 Over most of the range of this genus probably two or more 

 families are reared a season. Young may be encountered 

 in almost every month of the year wherever winter is not 

 severe, and the number in a litter varies from three to five. 



Genus Microdipodops 



Dentition: Incisors, {; Canines, ^ ; Premolars, |-; Molars, f =20. 



Dwarf Pocket Rat. — Microdipodops megacephalus 



and related forms 



Names. — Dwarf Pocket Rat ; Pigmy Pocket Rat ; Kangaroo 

 Mouse. 



General Description. — In general appearance like a large, 

 heavy-bodied Pocket Mouse (Perognathus); head large; hind 

 feet long; tail more than half total length; temporal region of 

 skull greatly inflated; hind feet with five toes, soles densely 

 haired ; habit nocturnal. 



Color. — Sexes colored alike; seasonal variation slight. 



Upperparts. — Yellowish brown finely mixed with black- 

 tipped hairs and slightly tinged with olive; pale ochraceous 

 wash on sides; tail above like back except for blackish on 

 terminal third; blackish crescent at base of whiskers; buffy 

 spot back of each ear. 



Underparts. — White with wash of pale ochraceous on belly. 



Measurements. — Sexes of equal size. Total length, 6 

 inches; tail vertebras, 3.2 inches; hind foot, i inch. 



Geographical Distribution.^ — Arid section of Great Basin 

 district where states of Oregon, Nevada, and California 

 meet, south as far as Mono County, Calif., east to Elko 

 County, Nev. 



Food. — Seeds and grains. 



Enemies. — Snakes, Owls, Foxes, Skunks, Coyotes, Weasels, 

 etc. 



Species and Subspecies of the Genus Microdipodops 



Nevada Dwarf Pocket Rat. — Microdipodops megacephalus 

 megacephalus Merriam. 

 As described. Found in Elko County, Nevada. 



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