RODENTIA-SCIURINAE-SPERMGPHILUS TRIDECEM-LINEATUS. 
317 
Arciomys hoodii, Griffith’s, Cuvier, LEI, 1827, 186 ; plate (original figure.)— Ib. Y, 1827, 247. 
Fischer, Synopsis, 1829, 544. 
Wagner, in Schreber Saugt. IV; pi. ccx, C. (no text.) 
ArcUmys (Spermophilits hoodii,) Rich. F. B. Am. I, 1829, 177 ; pi. xiv. 
Sperrnophilus hoodii, F. Cuv. Suppl. Buff. I, Mammif. 1831, 337. 
Prince Max. Reise in das innere Nord-Amerika, I, 1839, 449. 
Wagner, Suppl. Schreb. Ill, 1843, 251. 
Sp Ch.—A bout tbe size of Sciurus hudsmius. Ears very short. Tail vertebras about half the length of body, or a little 
longer Claws long ; that of thumb rather diminutive. Above dark brown, with light stripes and lines of light spots alter¬ 
nating with each other, six of the former and five of thelatter generally very distinct. Tail with a brownish yellow margin 
and tip, and within this a border of black. Length, 5 to 6 inches. Tail vertebra), 3.50 to 4 inches. Hind foot, 1.30 to 1.40. 
This species is in a measure intermediate between the form typified by S. ludovicianus and 
that of S. beecheyi. The ears are short and reduced to a mere rim, as in S. franlclinii, which, 
indeed, it resembles in many other respects. The claws are very long ; that on the thumb 
being very short, though decidedly claw-like, and not a mere nail. The soles are sparsely 
covered with long hair. The tail varies in length, though generally about half the length of 
the body, or a little more. 
The general color above is of a dark brown, sometimes nearly black, the lower parts of the 
sides and under parts light yellowish brown. The upper parts are longitudinally and symmet¬ 
rically striped with continuous yellowish white lines and lines of spots, the number distinctly 
traceable varying with the specimen. On each side of the vertebral line there are three well 
defined lines, most distinct on the middle of the body, with indistinct traces of one or two below 
these. The vertebral line itself is occupied by a row of spots, and all the spaces between the 
continuous lines described are similarly traversed, although two on each side the median line 
are all that are distinct. Anterior to the shoulders, the spots in each line generally become 
confluent. The top of the head is occupied pretty uniformly by spots. In some specimens 
there is a slight or obsolete interruption at intervals to the continuity of the stripes, caused by 
the darker tips of the hairs^ The tail is brownish yellow, with a broad subterminal band of 
black, the hairs being each so marked. In some specimens the central portion of the tail has a 
chestnut tinge, although the yellowish margin and tip, with the black line within this, are 
usually distinctly visible. 
In comparing an extensive series of specimens of this species from various parts of the country, 
those from Wisconsin are seen to differ quite materially from those further west, in a consider¬ 
ably larger size and darker color. The ground color between the stripes is of a very dark brown, 
almosj; black, and the stripes are rather further apart. The under parts, too, are perhaps a 
little more dusky. I do not, however, find any other characters of importance. The spots and 
lines are not so large in proportion as in the lighter prairie specimens. 
Measurements of slculls. 
No. 
Locality. 
Length. 
Width. 
No. 
Locality. 
Length. 
Width. 
1264 
Racine_ 
1. 59 
. 90 
835 
R. A. Jacques, Minn 
. 96 
919 
1. 68 
1. 00 
1303 
Head of Arkansas 
1. 40 
' . 82 
920 
_do______ 
1. 63 
1. 95 
1304 
__do 
1. 46 
.86 
1351 
Fort Kearney. 
1. 56 
