144 
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 
brownish white, with lighter tips. The convexity of the ears is grizzled like the hack; the base 
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 hack, instead of being rusty. The fur is softer 
and fuller, the coarse hairs not much exceeding the under fur. The tail is much shorter, hut 
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. 
Inches. 
Lines. 
Nose to occiput__ 
4 
4 
Nose to eye.------_ 
1 
6 
Nose to ear___ 
4 
3 
Nose to root of tail __ 
17 
Nose to end of outstretched hind leg_ 
18 
4 
Tail from root to end of vertebrae._ 
6 
Tail from root to end of hairs_-_ 
8 
Ears, height posteriorly -_ 
2 
1 
Ears, height anteriorly_ 
2 
2 
Ears, height internally above skull_ 
2 
Ears, width _ _ _ ________ 
1 
4 
Arm, between claws cross shoulder_- __ 
1 
3 
length of fore arm_ 
2 
3 
from elbow to end of claws_ 
4 
fore foot to end of claws_ 
2 
5 
longest claw_ 
5 
Leg, from knee joint to end of claws. _ . 
7 
tibia____ 
4 
hind foot from heel to end of claws_-_ 
3 
6 
longest claw_ 
4 
Shull .—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 
