128 



U. 8. P. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



Black Fox. The color here is a uniform lustrous black, with a distinct white tip to the tail. 

 On the top and sides of the head, however, and on the posterior half of the back, including the 

 outside of the thighs, the long hairs are grayish-silvery at the end, (the extreme tips black,) 

 grizzling the back very conspicuously. The same feature is observable at the base of the tail 

 and to some distance on its sides ; it is also seen slightly on the shoulders. The under fur is of 

 a sooty color, not very dark, however, and becoming lighter on the sides of the neck and 

 flanks. 



List of specimens. 



In the only one of the above specimens (1190) in which the feet are entire, the soles are much 

 less densely furred than in the cross foxes, and more nearly resembling the red fox of the eastern 

 States in this respect. It is by no means certain that these specimens are not black varieties of 

 the Vvlpes macrourus. 



Measurements of specimens of different varieties. 



1 Catalogued under the head of Vvlpet macrouriu. 



