ARCTIC FOX 



Genus Alopex 

 Dentition: Incisors, f ; Canines, { ; Premolars, | ; Molars, f =42. 



Arctic Fox. — Alopex lagopus 



and related forms 



Names.— Arctic Fox; White Fox; Blue Fox; Polar Fox. 



General Description. — A small Fox having rather short ears, 

 soles of feet heavily furred, and muzzle proportionally shorter 

 than in Vulpes; pelage very thick and long, color varying with 

 the season; tail bushy. Plate XIII. 



Color. — Sexes colored alike; a marked change with the 

 seasons. 



Summer. — Upperparts dark brown to slate color, with 

 whitish to yellowish white on underparts, sides of neck, and 

 flanks. 



Winter. — Everywhere clear white. 



Blue phase. — ^A color phase which bears about the same 

 relation to the normal pattern as does the Black or Silver 

 phase of the Red Fox to its more common pelage. Every- 

 where dark, smoky gray or bluish drab, sometimes with wash 

 of sepia on head and feet and with a few white hairs sprinkled 

 on throat and face. The "blue" animals do not turn white in 

 winter. 



Immature like adults in summer pelage. 



Measurements. — Females very slightly smaller than males. 

 Total length, 30 inches; tail vertebrae, 10 inches; hind foot, 

 4.5 inches; weight averaging around 10 pounds but varying 

 from 5 to 20. 



Geographical Distribution. — Arctic regions of Northern 

 Hemisphere. 



Food.— Small mammals, birds, eggs, fish,' carrion, sea- 

 urchins, etc. 



Enemies. — Wolves, Polar Bears, and possibly (when young) 

 Snowy Owls. 



Species and Subspecies of the Genus Alopex. 



Since there is such great similarity in color among the 

 various forms of the Arctic Fox, the bases for separation are 

 principally skull characters or differences in size. 



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