306 
U. S. P. R. R. EXP. AND SURVEYS—ZOOLOGY-GENERAL REPORT 
2. Similar to the preceding. The interval between the hoary patches dark 
brown, nearly black. 
3. Above, finely-grizzled gray and black. Anterior half of the body of a 
pure hoary gray cast; posterior half with a strong wash of yellowish, in 
marked contrast. 
4. Color entirely black.. 
2d. Tail about half the length of the body. 
5. On each side of the back two black lines, separated by a white one of about 
equal diameter. Middle of back finely grizzled, without any line. 
B. —Colobotis, Brandt. 
Ears apparently wanting, or with the auricle very slightly developed. Tail 
either very short or half as long as the body, or a little longer ; narrow and 
slender. Soles usually more or less pilose throughout the year. Thumb 
armed with a distinct sharp claw, (not a nail,) though sometimes quite small. 
1st. Ears rather short, but with a small, pointed, and perfectly distinct 
auricle. Tail half as long as the body. Soles pilose in summer. 
6. A distinct white stripe on each side, without any margin of black. 
7. Mottled yellowish gray and brown. Head pure gray, without any tinge 
of yellowish. 
2d. Ears very short, apparently wanting, in the dried shin. Tail variable- 
in size and length of hair. 
8. Tail very long, nearly equal to the body, exclusive of the head ; cylindrical. 
Color yellowish brown, finely pointed with black. Ho blotches or spots... 
9. Tail about two-thirds the length of head and body ; flattened ; well haired, 
though narrow. Above, with continuous lines of yellowish, alternating 
closely with lines of spots of the same color. 
10. Tail as in the preceding. Above, olivaceous brown, with lines of very 
distinct light spots only, these arranged in regular series. 
11. Tail somewhat as in preceding. Above, yellowish chestnut, with nume¬ 
rous more obsolete light blotches, not distinctly arranged in series, most 
conspicuous on the posterior portion of the back. 
12. Tail rather full; nearly half as long as the body. Above, with crowded 
indistinct subquadrate light spots. Top of the head chestnut.. 
13. Tail narrower ; one-third the body. Body uniform yellowish brown, with¬ 
out any spots, blotches, or stripes whatever. 
14. Tail very slender ^cylindrical; length one-fourth the body. Above, with 
numerous crowded obsolete, light, rounded spots or blotches. 
douglasii. 
grammurus. 
couchii. 
lateralis. 
harrisii. 
franhlinii. 
tereticaudus. 
tridecem-lineatus . 
mexicanus. 
spilosoma. 
parryi. 
richardsonii. 
townsendii. 
