620 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 
are scattered over the tail, and more evident ones clothe the instep; but the 
parts always present a peculiar skinny appearance. Tail less than one-fourth 
as long as the head and body; hands not as longas the feet; smaller and weaker 
than in the bursarius group; cheek-pouches are not so highly developed. As 
well as can be judged from prepared skins, the sacs do not reach to the 
shoulder; their capacity, in an individual ncarly a foot long, seems no greater 
than that of specimens of G‘. bursarius not more than half as bulky. The 
external meatus of the ear has a small flap. The hispid pelage is a remark- 
able feature, being coarse and harsh, almost entirely lustreless, longer than 
usual, and interspersed with still longer and almost bristly hairs; and the color 
is uniform to the roots of the hairs. It is characteristic of all the soft-haired 
species of Geomys to have plumbeous-colored fur at base, pointed with the 
particular brown, fulvous, or other shade which determines the appearance to 
the eye. In G. hispidus, the hairs are unicolor from base to tip; dark mahog- 
any-brown, or rather chocolate, a little lighter or darker according to age or 
season, or fortuitously, but uniform over all the upper parts and sides. Under- - 
neath, the color is paler, like café au lait; sometimes quite smoky-gray or 
muddy-brown. The under parts frequently show indeterminate patches of 
white. It is probable that plumbago-colored individuals occur, but I have 
seen nonesuch. The naked parts appear to have been reddish or flesh-colored ; 
claws horn-color; incisors faced with red. 
Note on a skull. 
In preparing the original memoir, I regretted that I had no skull of 
either of the Mexican species to describe. Since then I have found a defective 
specimen in the collection of the National Museum, marked “hispidus—Mex.” 
It is much larger than any United States specimen I have seen, measuring in 
total length (from occipital crest to incisive alveoli) 2.70 inches, with a width of 
1.85 across the widest part of the zygomatic arches. (A good-sized speci- 
men of G. bursarius measures in the same dimensions 2.25 1.50.) Greatest 
depth of skull, without jaw, 1.18 (opposite premolars; the corresponding dimen- 
sion of G. bursarius is only 0.70). Width across occiput, 1.65. Length of 
lower jaw (condyle to incisive alveolus), 1.80 (in G. bursarius, 1.45); great- 
est divergence of rami of the jaw (at the exflected angles), 1.80. The enor- 
mous under incisors protrude more than an inch—1.25; the upper incisors 
are exserted for 0.65. The zygomatic width is increased by a well-marked 
