496 
U. S. P. R. R. EXP. AND SURVEYS-ZOOLOGY-GENERAL REPORT. 
The general color of this animal above is a mixed black and liglit reddish brown, the latter 
color predominating on the sides, so mncb in some specimens as almost to constitute a stripe; 
on the dorsal region it is much obscured by black tips to the hairs. The under parts are of a 
soiled yellowish white, the line of demarcation passing low on the cheeks and belly, where the 
white does not occupy scarcely more than one-third of the entire circumference. The exterior of 
the limbs, including anterior and posterior edges, is like the back, the color coming down to the 
very wrist of the hand, and not only reaching to the ankle joint of the hind foot, but extending 
over the metatarsus to the bases of the toes. This character is constant in all the California 
specimens I have seen. The tail is uniformly dusky all round ; not lighter below. 
The fur is rather long, coarse, and somewhat stiff. I have not been able to detect any under 
fur, even in winter specimens. 
The five specimens from Santa Clara and Petaluma all present a striking constancy in the 
great length of tail and its dusky color, the dusky hind feet, and other characteristics. In 
many respects—size, color, dusky feet, &c.—there is a very close resemblance to the Neotoma 
occidentalism from which the nearly naked tail will at once distinguish them. 
The considerably longer tail, dusky feet and tail, and larger size, will readily distinguish this 
species from all the others described as North American. 
List of specimens. 
Catalogue number. 
Corresponding number 
of skull. 
Sex and age. 
Locality. 
When 
collected. 
Whence and how 
obtained. 
Nature of speci¬ 
men. 
Measurements. 
Tip of nose to— 
Tail to end of 
verteb. 
Length of— 
Skull- 
Height of ear. | 
•aXa 
UE3 
d 
O 
'I! G X 
Fore ft. 
Hind ft. 
| Length, j 
Width. 
2679 
$ 
Petaluma. CJal t .. 
Feb., 1856... 
E. Samuels ........ 
In alcohol. 
1.07 
2.00 
2.40 
8.20 
7.90 
.85 
1.58 
2680 
...... do. 
.. ...do . 
., ....do. 
..do .... 
.86 
1.56 
1.93 
6.25 
6.15 
.76 
1.22 
1158 
2040 
Santa Clara, Cal. 
Nov., 1855... 
Dr. J. G. Cooper ... 
Skin. 
3.25 
9.00 
8.50 
.75 
1.55 
2.15 
1.15 
1159 
2041 
_ __do. 
6.50 
.80 
1.60 
1182 
O 
...... do. 
.do t T T T 
do t T T . . . 
9.50 
7.00 
1.42 
.90 
1 
NEOTOMA OCCIDENTALS, Cooper. 
Hairy-tailed Rat. 
Neotoma ocddentalis, (Cooper, Mss.) Baird, Pr. A. N. Sc. Pliila. VII, April, 1855, 336. 
Neotoma drummondii, Add. & Bach. N. Am. Quad. I, 1849, 223 ; pi. xxix. 
Sp. Ch. —Size that of the Norway rat. Fur rather harsh, not compact. Tail densely hairy ; the vertebras as long or 
longer than the body, exclusive of the head ; above, broadly grayish lead color, the basal wool but little lighter. Posterior 
third of soles furred. Body above, brownish plumbeous, with a slight mixture of yellowish brown. Under parts of body 
and tail, with feet, bluish white. 
In size this animal equals or exceeds the Norway rat, Mus decumanus, to which, however, with 
its large ears and bushy tail, it has little resemblance. The whiskers are stiff, and longer than 
the head ; the head elongated and acute. The eyes rather large. The ears large, broad, and 
thin, scantily clothed with pretty long hairs. The feet are moderately large ; the thumb, as 
usual, a rudimentary tubercle or knob, with a broad nail; the fourth finger longest; the third, 
