RODENTIA-SCIURINAE-ARCTOMYS LEWISII. 
347 
name of Ardomys monax, and eays that they agree exactly with the figure by Audubon and 
Bachman of A. prxdnosa, (the same one just described.) The paws of the Asiatic specimens he 
states, however, to he yellowish brown, instead of black, although the intermixture of single 
blackish brown hairs suggests the possibility of their varying to this extent. From the analogy 
of Spermophilus parryi, it would seem highly probable that the same species might inhabit the 
adjacent shores of the North Pacific. 
MiddendorfF is inclined to think that Ardomys caligala of Eschscholtz may be distinct from 
the A. pruinosus, as its color is much lighter, and the tail measures ten inches in length, or about 
half the length of the body, both according to Eschscholtz’ description and a skin brought sub¬ 
sequently from California by Wosnes’ens’kij, a taxidermist in the employ of the Academy of 
Sciences of St. Petersburg, who spent several years in the Russian possessions on the Pacific. 
ARCTOMYS LEWISII, Aud. & Bach. 
Lewis’ Marmot. 
Jlrctomys lewisii, Aud. & Bach. N. Am. Quad. Ill, 1853, 32; pi. cvii. 
“ Sp. Ch. —Size of the gray rabbit; shape of head and body similar to that of Jlrclomys monax. Tail, with the hairs, about 
one-fifth the head and body. Nose and nails black. Upper surface and ears reddish brown, the softer dense under fur being 
light yellowish brown, the longer interspersed hairs blackish brown at the tips. On the haunches the hairs are interspersed with 
black and yellowish brown; feet and belly light salmon red. Tail from the root, for half its length, reddish brown; the other 
half to the tip, soiled white. Above the nose, edges of ears, and along the cheeks, pale reddish buff. There is a white band 
across the toes, and another irregular one behind them; there is an irregularly defined dark brown line round the back of head 
and lower part of the chin, marking the separation of the head from the throat and neck.” 
Inches. 
Length from nose to root of tail____ 
16 
Tail, (vertebras)___.._ 
2 
Tail, with hairs_ 
3 
Nose to Gar___ 
3 
Nose to eye___ 
1 
Heel to middle claw__ _ 
H 
The specimen described as above was found by the authors in the museum of the Zoological 
Society, where it is labelled “ Ardomys brachyura? No. 461.” It was received from some of 
western British fur posts, and supposed to have been collected somewhere in the vicinity of the 
Columbia river. 
From the description, as well as the figure, I should be inclined to consider this animal rather 
as a prairie dog ( Cynomys ) than as a true marmot {Ardomys). The tail and feet are much 
shorter in their proportions than in our other Ardomys , but agree very closely with the other 
genus. Thus, in a fresh specimen of the Missouri prairie dog, (No. 1803,) the head and body 
measure 13 inches ; the head alone, 3|; nose to ear, 2| ; the hind foot, 2.38. The tail is 
nearly twice as long as in A. lewisii . A very little stretching of the skin, which it could 
scarcely fail to receive after stuffing, and especially if prepared as hunters’ skins usually are, 
would bring these measurements to. 16 inches for the length to root of tail, and one-eighth of 
an inch added to the hind feet would make up three inches. Now, in a fresh specimen of A. 
