MAMMALS—CANIDAE—VULPINAE. 121 
Sus-Famiry VULPINAE. 
Pupil of the eye elliptical. Head slender. Upper incisors scarcely lobed. Post-orbital process of the frontal bono bent but 
little downwards, the anterior edge turned up ; a longitudinal shallow pit or indentation at its base. 
It is in this group of the Canidae that we find the animals known in North America and the 
Old World as foxes, several species of which belong to this continent. Among these there 
are several very distinct types, with one or more species in each. In the one, the tail is uni- 
formly bushy all round, composed of long hairs mixed in among the short fur, in nearly uni- 
form proportion. The skull is more or less wolf-like in shape ; the temporal crests generally 
approaching each other and nearly coalescing as far forward as the parieto-frontal suture or 
farther. The muzzle is long, and the centre of the bony orbit falls about opposite the middle 
of the axial line of the head. ‘To this group the name of Vulpes should be applied. 
In the other section, illustrated by the gray fox of North America, the temporal crests never 
approach each other, but are separated on the parieto-frontal suture by a space of nearly an 
inch. The muzzle is very short, though pointed ; the centre of the bony orbit anterior to the 
middle of the axial line. The most striking feature, however, is in the tail, which, instead of 
being uniformly bushy, as in the red fox, exhibits, on close examination, a concealed erect mane 
of stiff hairs along the upper line, unmixed with fur at all, on each side of which the rest of 
the hair is arranged, falling down on the sides in a manner quite different from what it is in 
the red fox. To this group, if of generic value, may be applied the name of mane-tailed foxes. 
The following diagnosis will serve to show the points of contrast more clearly : 
A. Tail with soft fur and long hair, uniformly mixed. Muzzle long. Temporal crests 
coming nearly in contact.— VULPES. 
B. Tail with a concealed mane of stiff hairs, without any soft fur intermixed. Muzzle short. 
Temporal crests always widely separated. A supplementary tubercle on the lower sectorial. 
The under jaw with an angular emargination below.—Unrooyon. 
In order to illustrate more fully the detailed descriptions of the skulls of the different Ameri- 
can foxes, and the comparison of the European V. vulgaris with its allied American species, I 
have prepared several comparative tables of measurements and proportions, which may not be 
without interest. I need hardly repeat here what I have already stated, that all these statistics 
are entirely original, and, like the descriptions of the animals themselves, based on the exami- 
nation of specimens in the Smithsonian collection, unless when stated expressly otherwise. 
16 L 
