4 Myron Harmon Swenk 
are abundant everywhere and densely crowded on the neck, 
shoulders and hips, and become more or less tinged with yellow 
basally on the sides of the lower back and rump; all of this more 
or less overtopped with long, straight, coarse, bristle-like hairs 
which are concolorous with the underfur all or most of their 
length (pure white at extreme base), the wholly black ones being 
most numerous dorsally, the others having the apical exposed one- 
fourth or one-fifth very pale yellowish gray to greenish yellow, 
these partly yellowish hairs few and scattered dorsally but numer- 
ous and with a more pronounced yellow cast on the lower 
shoulders, sides and especially the flanks, the rump and median 
area of the upper side of the tail without long hairs; under parts 
along the midventral line with soft, fine, sooty brownish hairs, 
these becoming stiffer and white at their bases toward the sides 
and rather heavily overlaid with the long bristle-like hairs of the 
overfur, like those above but usually with more extensively white 
bases; the long, yellowish-tipped hairs of the overfur become 
stiffer and yellower over the flanks and extend down the sides 
of the tail as long, very heavy, pale yellow, spinous bristles con- 
cealing numerous yellowish white to white quills, the under side 
of the tail with rather short, exceedingly dense and hispid or 
spinous bristles which toward the base of the tail are mostly 
brownish yellow but become increasingly intermixed with black, 
so that the terminal one-half of the tail is blackish ; nose, forehead 
to interorbital line, a ring around eyes, anterior cheeks, chin and 
throat covered with short, wholly blackish or brownish hairs, these 
abruptly intermixed on the forehead and cheeks posteriorly with 
stiff, appressed, whitish hairs that cover small, white quills and 
these developing on the occiput and nape to the normal, long 
overfur hairs and quills; whiskers jet black; legs with the under- 
fur brownish sooty more or less overlaid with greenish yellow to 
pure gray-tipped hairs. (Description of type ¢'; September.) 
Adult in summer pelage: Like the winter adult but general 
color much darker owing to the reduction of the long, greenish- 
yellow tipped hairs of the overfur which more largely exposes 
the black underfur. (Description of a living specimen captured 
at Scottsbluff, July.) 
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