288 University of California Publications in Zoology. \|Vou.5 
is no patchy appearance, except in one (no. 8259), the molt 
appearing to proceed regularly commencing at the nose. 
The form trepidus is distinguished by certain leading char- 
acters from any previously described similar species known to 
the writer. From wortmani (Allen, Bull. Am. Mus. Nat. Hist., 
VII, November 8, 1895, p. 335, type locality Kinney Ranch, 
Bitter Creek, Wyoming) it is differentiated by the presence 
dorsally of the broad inner lateral black stripe; from lateralis 
(Say, Long’s Exped. Rocky Mountains, II, 1823, p. 46, type 
locality ‘‘Near the Source of the Arkansas River, Colorado’’) 
by the much broader inner lateral black stripe (dorsal) ; from 
cinerascens (Merriam, N. Am. Fauna, no. 4, Oct., 1890, p. 20, 
type locality Helena, Montana) by a number of color differences 
and much smaller size; from castanurus (Merriam, l. c¢., p. 19, 
type locality Park City, Wahsateh Mountains, Utah, altitude 
7000 feet) by the ochraceous instead of chestnut color of the 
under surface of the tail; and from chrysodeirus (Merriam, l. c., 
p. 19, type locality Fort Klamath, Oregon), by the differences 
above outlined. 
In the original description of wortmani (1. c.) Allen makes 
the assertion that the new form (7.e., wortmani) combines in a 
singular manner the characters of the two “‘couplets’’ into which 
Merriam a few years since (N. Am. Fauna, no. 4, Oct., 1890, p. 
18) separated the lateralis group. This statement may seem- 
ingly be even more appropriately applied to trepidus. In eranial 
characters it much resembles the castanurus group, but certain 
external characters point strongly in the direction of the lateralis 
group. For example it has the inner lateral black stripe on the 
back narrower than the outer, and possesses a distinet second 
lateral black band (concealed) on the tail. It should perhaps 
be noted in passing that specimens of chrysodeirus in the Museum 
have the bases of the lateral tail hairs plumbeous or black. One 
individual (no. 3301) possesses the second lateral band (con- 
cealed) somewhat as in lateralis. 
DIsTRIBUTION.—Specimens of the Nevada golden-mantled 
ground squirrel were collected as follows: Big Creek Ranch, 
16; Big Creek, 10; Leonard Creek, 2; Duffer Peak, 4; Alder 
