THE GLANDS. 259 



and six lines at the upper end, but is narrower below the gland. 

 About six lines below the upper end of this tuft commences the 

 upper end of the naked space over the gland. This naked space 

 is from five inches and one line to six inches long on very lai'ge 

 specimens, and from four lines to half an inch broad, and is cov- 

 ered by a black scale of the concentrated exudation. (Fig. 5, p. 

 258.) The gland extends beyond the naked portion so that its 

 borders are under the tuft of hairs, but the portion covered with 

 hairs is much less active than the naked portion, so that the 

 encroachment of the hairs would seem to be gradually obliter- 

 ating the gland, or the advancement of the gland, by degrees 

 displacing the hairs. The elevated hairs on either side of the 

 gland approach each other over its centre, and then when they 

 meet turn back and so form a sort of seam directly over the organ. 



I have critically examined a great number of specimens, and 

 have found this organ remarkably uniform in all, varying only 

 in extent according to the size of the animal. Not a single white 

 or black hair ever occurs in the tuft, but the whole surface is a 

 uniform, tawny yellow of exactly the same shade as on the rest 

 of the leg. Nor is the inside black as is the tuft on the inside 

 of the hock just described, but the lower part of the hairs is of 

 a lighter shade than the outer portion. I could never observe 

 these to be disturbed by excitement as is the case with the other. 



I here present illustrations of these glands of all our species on 

 which they are found, and also on the small deer from Ceylon, 

 with the tufts of hair which cover them, opened so as to expose 

 the naked portions covered with the black incrustations. By 

 seeing them thus brought together, we are the better enabled to 

 compare them. 



In this glandular system the Black-tailed deer, C. Oohimbianus, 

 as well as in some other peculiar characteristics, is nearest allied 

 to the mule deer, as we shall see in another place, although in 

 other respects these species are widely divergent. The meta- 

 tarsal gland commences a little lower down on the metatarsus, 

 than on the mule deer, and its tuft of long partially reversed 

 hairs occupies a space about four inches long and fully one inch 

 broad. On a large specimen the naked crusted portion is two 

 inches in length and scarcely three lines broad. The hairs of 

 this tuft are disposed much as on the mule deer, though the 

 central seam over the gland is not so well defined.. Like the 

 other it corresponds exactly in color with the hairs on the rest of 

 the leg, without a single white or black hair in the region, and 



