478 
IX. S. 1\ R. R. EXP. ANU SURVEYS — ZOOLOGY-GENERAL REPORT. 
List of specimens. 
Measurements. 
Catalogue number. 
a 
6 
Age and sex. 
Locality. 
When col¬ 
lected. 
Whence and how ob¬ 
tained. 
Nature of 
specimen. 
| Nose to eye. 
| Nose to ear. 
| Nose to occiput. 
| Nose to tail. 
| Tail to end of vert. 
Tail to end of hairs. 
| Length of fore feet. 
Length of hind feet. 
3 
Height of ear. 
989 
2020 
Racine. Wisconsin. 
Dr. P. R. Hoy..... 
Skin. 
P553 1 
1673 
0 ! 
.50 
.83 
1.04 
3.00 
2.17 
2.33 
.42 
.70 
.97 
.44 
2667 
V 
In alcohol... 
.48 
.80 
1.00 
3.18 
2.22 
.34 
.74 
.40 
2668 
.. ! 
.45 
.85 
2.82 
1.82 
1.9$ 
.30 
.70 
.50 
P2669 
.do... 
. ! 
.44 
.85 
.30 
.68 
.43 
650 
West Northfield, Ill 
April 18,1855 
R. Kennicolt.... 
Skin. 
739 
May 13,1855 
-do ..... 
2756 
In alcohol... 
.43 
.75 
.99 
2.70 
1.70 
.35 
.68 
.44 
2757 
Q 
.48 
.82 
1.43 
3.03 
1.92 
2.02 
.30 
.70 
.48 
2758 
d0 .. 
.do .. 
....do. 
.45 
.78 
1.00 
2.95 
2.02 
.30 
.68 
.45 
2759 
1.10 
3.20 
2.25 
2.33 
.35 
.70 
.48 
2760 
s 
.do . T ,. 
.50 
.85 
1.05 
2.94 
2.45 
.32 
.71 
.48 
2761 
s 
_ do. 
.46 
.78 
1.04 
2.85 
2.20 
2.37 
.30 
.46 
2763 
g 
.52 
.87 
1.05 
3.43 
2.55 
2.72 
.36 
.70 
.55 
2764' 
3 
.45 
.75 
.96 
2.92 
2.05 
.30 
.65 
.50 
2765 
3 
.51 
.87 
1.10 
3.20 
2.19 
2.35 
.35 
.75 
.48 
2766 
$ 
.do. 
.45 
.82 
2.90 
2.08 
2.26 
.30 
.65 
.48 
2771 
g 
..do. 
.50 
.85 
1.08 
3.32 
2.18 
2.32 
.70 
782 
3 
Tremont, Ill. 
W. J. Shaw. 
Skin. 
645* 
1796 
Sf. Louis, Mo.,... 
Dr. Engelmann.. „ 
.,..do. 
.84 
3 00 
1.84 
2.00 
.9' 
646° 
1797 
.do. 
_do. 
1.08 
2.93 
1.93 
12.00 
701* 
1864 
.do. 
.84 
2.60 
2.00 
12. 11 
.90.... 
...... 
1 Measured before skinning. Fore arm, .55 ; from elbow to end of claws, .90; longest fore and hind claws, each, .06; from knee joint to end of 
claws, 1.42; tibia, .83; mamm$ 4 abdominal, two pectoral. 
2 Measured before skinning. 
HESPEROMYS CALIFORNICUS. 
Mus californicus, Gambel, Pr. A. N. Sc. Phila. IV, August, 1848, 78, (Monterey.) 
Sp. Ch.—V ery large. Size of third grown rat. Ears very long, angular. Tail rather longer than body. Color above, 
sooty brown, passing on the sides to fulvous. Under parts white, tinged with fulvous and ashy. Feet white. Tail 
brown, a littler darker on the dorsal line. Soles entirely naked. 
This is one of the largest, if not the largest, of the North American Hesperomys, with the 
exception of the IT. palustris of Georgia. The ears are enormously large, in this respect cer¬ 
tainly exceeding any other species; they are considerably higher than broad, and, instead of 
being rounded uniformly at the tips, are cut at nearly a right angle with the corners rounded. 
They are uniformely coated with short white hairs, which do not form a fringe, as on Neotoma. 
The hind feet have the soles naked from the heel. The tail is considerably longer than the 
body, very thick and stout, as in the rats. The fur is very soft and full. 
The middle of the hack of this species is a mixed black and grayish plumbeous, the former 
greatly predominating ; towards the sides there is less black, and light brownish yellow makes 
its appearance, forming quite a conspicuous stripe on the lower part of the sides, less distinct 
on the cheeks. The dusky extends to the wrist and heel, though the upper surfaces of the feet 
are entirely white. The under parts are dull whitish, strongly tinged in places with fulvous, 
