268 VERTEBRATE ANIMALS OF THE UNITED STATES 



lands and mountains of the Great Basin and Rockies and the Sierra 

 Nevada from British Columbia to Mexico. 



C. microdon Merr. Color cinnamon rufous; length 1,070 mm.; tail 

 320 mm.; hind foot 186 mm.; teeth very small; hind foot whitish above: 

 lower Rio Grande region. 



C. mearnsi Merr. Similar to C. microdon in size ; color fulvous and 

 very rich and bright: Arizona. 



C. ester Merr. Similar to C. mearnsi in size and color, but paler, 

 being a pale desert form: eastern California, Nevada and Utah. 



C. ochropus Eschscholtz. Similar to C. lairans, but smaller and 

 darker; ears large; head small: San Joaquin Valley, California. 



2. Vulpes Oken. Red foxes. Upper incisors not lobed ; legs rather 

 short; tail bushy, with soft under-fur: about 20 species, all in the 

 northern hemisphere, 10 in the United States, all valuable fur-bearing 

 animals. Their dens are holes in the ground dug by themselves, and 

 they bear 4 to 9 at a birth. 



Key to the United States Species of Vulpes 



ai In the eastern and central States. 



bi In the States east of the Mississippi T'. fulva. 



b2 In Nova Scotia and Labrador V. rubricosa. 



hi In Newfoundland V. deletrix. 



as In the western States, 

 bi On the Great Plains. 



Ci In the northern States and Canada V. regalis. 



C2 In the central Mountain States V. velox. 



C3 In the southwestern deserts V. macrotis. 



\>2 In the mountains. 



Ci In the central Rockies V. macroura. 



C2 In the Sierras and Cascades V. cascadensis. 



C3 In the high Sierras V. necator. 



bz In central California V- mutica. 



V. fulva (Desmarest). Red fox; black fox; cross fox; silver gray 

 fox. Color reddish gray; feet and ears black; tail darker than body; 

 tip of tail and under parts white; melanic individuals sometimes occur, 

 the black fox being entirely black, the cross fox having a black band 

 along the back crossed by one on the shoulders, and the silver fox being 

 silver gray; length 1,034 mm. ; tail 394 mm. ; hind foot 163 mm. : eastern 

 America, southward to Georgia and Tennessee; northward to Maine; 

 westward to the Great Plains; introduced into other regions. 



V. rubricosa Bangs. Size slightly larger and color deeper than V . 

 fulva; tail very dark, with a basal ring of black: Nova Scotia and 

 Labrador. 



