654 U. Ss. PP. R. R. EXP. AND SURVEYS—ZOOLOGY—GENERAL REPORT. 
the line of junction of the hair, is about three-fourths the length along the upper edge. The 
extreme width of the entire hoof is about four-fifths this length. In the fore hoofs, the length 
along the upper edge, is a little less in proportion to the other dimensions than in the hind legs. 
The gland on the hind leg is much as in C. virginianus. It is situated along the middle 
of the bone, and is rather longer than the bone is wide ; it is narrower than in C. virginianus, 
but perhaps longer. It is surrounded by a dense tuft of hair a little lighter than on the rest of 
the leg, but otherwise’ not so conspicuously different as in C. virginianus. 
The prevailing color of this animal is an ashy brown; pointed with light gray or dull whitish. 
The hairs themselves are generally light gray at the base, the terminal portion becoming of a 
pure brown, (without any shade of red or yellow,) darkest near the tip, where it is rather broadly 
annulated with light gray, clearer than at the base, and with perhaps a faint tinge of yellowish. 
The under surfaces are lighter; the only pure white appears to have been in the inguinal region. 
The tail is entirely white beneath and all round. At the base above it is gray like the back ; 
the subterminal portion is whitish with a pale rufous tinge. The bases of the hairs above, 
however, except perhaps at the extreme end of the tail, are dark brown, darkest towards the tip. 
The head, including the convexity of the ears, presents the same grayish or pepper-and-salt 
color of the rest of the body. The end of the muzzle is encircled by a dusky ring passing just 
behind the naked muffle ; this ring is quite distinct on the side of the lower jaw, but for the 
rest is rather obsolete, being replaced by a grayish shade. The side of the muffle on either side 
of the nostrils and the tip of the chin are white. There is an increased amount of light in the 
mottlings of the muzzle just behind the dark band referred to, but no distinctly light ring. 
The under surface of the head is white. - 
No reliable measurements of this specimen can be taken, owing to the shrivelled state of the’ 
skin. It is not more than two-thirds as large, however, as the female C. virginianus, and may 
be still smaller. - 
This species, now for the first time included within the limits of the fauna of the United 
States, has, as already stated, many points of close relationship with the C. virginianus. It 
differs from it, however, in its much smaller size, shorter and whiter tail, grayer color, and 
other features. The colors are much grayer than in any winter C. virginianus I have ever 
seen, exhibiting no trace of the rusty or chestnut of the latter. The hoofs are shorter, broader, 
and higher. The tail is considerably shorter and lighter above, exhibiting no exposed black 
whatever. The ears are thinner. The head generally is much more uniform in its markings 
than in C, virginianus. 
I regret that no horns of this species were brought home, and that the single specimen is in 
such condition as to prevent any very accurate description. There is some doubt as to whether 
it is the true C. mexicanus of authors. I shall, however, apply the name provisionally. 
It is a little curious that this species, which, from the testimony of Dr. Kennerly, does not 
change color materially with the season, should present, as the permanent color in its southern 
clime, a grayish tint that resembles most closely the winter color of C. virginianus. A similar 
analogy is seen in the mottled owl; the Scops asio of the north, like the deer, being found both 
red and gray, (in the same season, however,) while its southern representative, Scops McGallii, 
from the Rio Grande, like the Sonora deer, is exclusively gray. 
