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



and sides are of a mixed grayish white or hoary, and black. The under parts are of a dull 

 hrownish white, with lighter tips. The convexity of the ears is grizzled like the hack ; the hase 

 of the ears, sides of the neck, a considerable portion of the limbs, and lower part of the sides are 

 light rusty or cinnamon. The sides of the muzzle, midway between the eye and the nose, with 

 nearly the entire chin, together with the margins of the lips, are black; the lower half of face 

 and part of the throat, pure white. The tail is hoary on the sides, rusty beneath, with a well 

 defined narrow stripe of black above. It has the same concealed mane of stiff bristly hairs as 

 the gray fox. 



This animal differs very slightly in appearance from the average of gray foxes. The convexity 

 of the ear is nearly of the same hoary-gray as the back, instead of being rusty. The fur is softer 

 and fuller, the coarse hairs not much exceeding the under fur. The tail is much shorter, but 

 this character cannot be relied on as permanent. The chief external distinction is that of size, 

 the head and body measuring in a perfectly adult animal but 18 inches, instead of 24 to 28. 

 The tail is only about 6 inches. 



Measurements from a specimen in alcohol. 



Skull. The skull of this diminutive fox, the smallest of those belonging to the American 

 continent, bears a very close relationship to the gray fox, although it differs in some appreciable 

 features. It is very considerably smaller, a fully mature skull measuring barely four inches by 

 2.08, while a corresponding one of the other species measures 4.80 by 2.60. 



The nasal bones are short, about three- tenths the length of the skull. They are broader than 

 in V. virginianus, narrowest near the middle, posterior to which they expand, and finally round 



