270 U. S. P. R. R. EXP. AND SURVEYS-ZOOLOGY-GENERAL REPORT. 
claw of the fourth. The under part of the foot, from the heel nearly to the base of the toes, or 
to the callosities, is densely coated with short grayish hairs ; and the sides of the toes being 
similarly coated, the ends of the hairs here project beyond so as almost to cover the inferior 
surfaces, which, in fact, are actually provided with scattered hairs. 
The tail with its hairs is rather shorter than the body. It is much flattened, as in Pteromys, 
hut narrow, scarcely exceeding an inch and a half in a natural expansion. 
The prevailing color of the upper parts and sides and the under surface of the tail is a yel¬ 
lowish rusty, mixed with black by the fine annulations on the distal third of the hairs, their 
basal portion being dark lead color. The dorsal surface, however, for about the width of the 
tail, as well as the upper surface of the tail itself, are washed with dark ferruginous. This 
color is seen, likewise, on the top of the head. The sides of the head are mixed gray, a ring 
around the eye, and the whole under parts dull silvery white. In some specimens the hairs on 
the latter surface are unicolored to the roots, which, in others, are lead colored. The colors of 
the belly and sides are separated by a dusky stripe. The tail, as stated, is ferruginous above, 
grayer beneath. It is margined all around by pale yellowish red, darker at the tip. Within 
this is a narrow border of black, of greatest extent at the tip. The single hairs at the end of 
the tail are brown at base, then ferruginous, then black and tipped with ferruginous ; on the 
sides they are similar, hut the tints lighter; beneath, they are mixed brown and pale yellowish 
brown ; above, they are nearly uniform ferruginous, with little, if any, annulation—a character 
seldom seen in squirrels. 
Measurements of a dried skin, No. 184. 
Inches. 
Lines. 
Length to root of tail_ 
7 
6 
Tail to end of vertebras_...... 
4 
6 
Tail to end of hairs___ 
7 
3 
Height of ears_____ 
5 
Hind foot from heel__ 
1 
11 
Measurements of specimens in alcohol. 
Number. 
Locality. 
From tip of nose to- 
Tail to end of— 
Length of— 
Eye. 
Ear. 
Occip. 
Tail. 
Yerteb. 
Hairs. 
Fore ft. 
Hind ft. 
2427 
Carlisle. 
.8 
1. 50 
2. 00 
7. 25 
5.00 
6.50 
1. 20 
1. 80 
2428 
.8 
1.50 
1. 85 
7.00 
6.00 
6.25 
1.10 
1. 75 
2429 
Monticello, Mississippi- 
.8 
1. 50 
1. 85 
6. 25 
3.50 
4. 25 
.80 
1.30 
Specimens vary from this description in the less intensity of ferruginous above ; in a greater 
amount of grayish on the sides ; in the ferruginous of the dorsal region being narrower and 
more concentrated. I have occasionally seen specimens in which the upper parts were nearly 
uniform gray and black, the former with the slightest possible mixture of rusty. 
