274 VERTEBRATE ANIMALS OF THE UNITED STATES 



length 1,540 mm.; tail 120 mm.; weight up to 500 lbs. : forest lands of 

 North America north of the Gulf States and the Sierra Madre in 

 Mexico; Hudsonian, Canadian, Transition and Upper Austral zones; 

 cHmbs trees readily. 



Subspecies of U. americanus 



U. a. americanus Pal. North America. 



U. a. amblyceps Baird. Color brown: southern Texas, New Mexico 

 and Arizona. 



U. a. floridanus Merriam. Head very long, high and narrow: 

 southern Florida. 



U. luteolus Grifhth. Color yellowish brown, darker on the nape; 

 similar to U. americanus, but with a long, flattened skull: Louisiana 

 and eastern Texas. 



U. horribiUs Ord. Grizzly bear. Color brownish yellow, being 

 darker on the back and legs; fur long and shaggy; length 2,500 mm.; 

 weight up to 1,000 lbs. : western America from Mexico, New Mexico and 

 Arizona to Alaska and Hudson Bay; does not climb trees, except when a 

 cub. 



, Subspecies of U. horribiUs 



U. h. horribiUs Ord. Utah and northward. 



U. h. horricBus Baird. Size smaller; the frontal bones flattened and 

 concave between the postorbital processes: New Mexico and Arizona to 

 Utah and Colorado. 



U. h. caUfornicus Merr. Size large; ears longer: central and 

 southern California. 



Family 2. Canidae. — Dogs, wolves and foxes. Body slender, 

 "with long legs; feet digitigrade; toes 5-4; claws blunt and non-retractile; 

 head elongate; dentition 2)l3, i/ij 4/4^ 2/3 (Fig. 139): cosmopohtan; 

 about 50 species in North America. 



Key to the United States Genera 



ai Pupil round; dogs and wolves i. Canis. 



a2 Pupil elliptical; tail bushy; foxes. 



bi Tail with soft under-fur 2. Vulpes. 



hi Tail with coarse fur 3. Urocyon. 



I. Canis L. Dogs and wolves. Legs long; tail moderately bushy; 

 upper incisors distinctly lobed: many species; cosmopohtan; about 24 

 in North America, and 15 in the United States. The domestic dog, 

 C. famiUaris, is descended from a number of wild stocks. The native 



