164 
U. S. P. R. R. EXP. AND SURVEYS-ZOOLOGY-GENERAL REPORT. 
PUTORIUS RICHARDSONII. 
Mustela richardsonii, Bonaf. in Charleswort'n’s Mag. N. H. II, Jan. 1838, 38. (“ M. erminea, Rich. F. B. A.”) 
Putorius richardsonii, Bp. in Rich. Zool. Beechey’s Voyage, 1839, Mammalia, 10.* 
Mustela ( Putorius ) erminea, Rich. F. B. A. I, 1829, 46. 
Mustela erminea, Thompson, Hist. Vermont, 1842, 31. 
Putorius agilis, A. ud. & Bach., N. A. Quad. Ill, 1853, 184; pi. cxl. 
Sp. Ch. —Length to tail, 9 inches or less. Tail vertebrae about half this length. Black of tail nearly one-half to one-third 
its length. Outstretched hind feet reach to the middle of the tail, (with hairs,) or a little beyond. In summer, dark chestnut 
brown above; whitish beneath. Whole upper jaw brown. In winter, white. Tail with black tip. 
A specimen in alcohol, which I refer to this species, is much smaller than skins of P. novebo- 
racensis, though perfectly adult. Its colors, moreover, are darker than in the larger species. 
It was caught in the spring of 1855, and consequently may he considered as having attained its 
full growth. The ears are large and somewhat pointed ; the false lobe, however, does not 
extend very high up. The centre of the eye extends rather more than midway between the nose 
and anterior edge of the ear opening. The feet are moderately large ; their under surfaces not 
very densely furred, allowing the tubercles to he readily visible. The hind feet outstretched 
reach midway along the vertehrse of the tail ; these vertebraa being more than half the length 
of body, with the hairs, about five-eighths. 
The upper parts are of a dark chestnut brown, with hut little reddish, this color pervading 
the tail, perineal region, legs and feet. The under parts are white, though much restricted ; 
the line of separation quite low down, beginning at the angle of the mouth, not on the upper 
jaw or nostrils, and extending on the inside of the fore leg to the wrist, and on the thighs. 
The flattened tail throughout is darker than the hack, on its upper surface, and the gradation 
into the black tip imperceptible, although the terminal half above, and nearly as much below, 
are entirely black. The hairs at the end of the tail, though long, do not, in this summer 
specimen, form a brush as in some other species ; indeed, the tail in the parallelism of its sides 
and depressed shape is not dissimilar to that of Tamias. 
In an alcoholic specimen from Middleboro’, (2316,) of rather small size, the body is seen to 
he of very slender and delicate proportions, much resembling those of P. cicognanii. The verte¬ 
hrse of the tail are about half as long as the head and body. The outstretched hind feet reach 
to the middle of the tail, hairs included. The tail is decidedly depressed, and distichous. The 
colors are much as in the Boston specimen. The upper lip is entirely brown, without white 
edge, as in other ermines. The legs are entirely brown. The black tip to the tail is nearly 
half its length on the under side. 
The feet are much smaller, more slender and delicate than in the P. noveboracensis; the 
tubercles larger. Although actually larger in body, the feet are relatively smaller than in 
P. cicognanii. The tail, of course, is considerably longer. The ears are higher and narrower 
at the base than in the last mentioned species. 
A summer specimen from Steilacoom (654) agrees very well with those from Massachusetts, 
excepting in having the peculiar reddish tinge to the under parts, so generally seen in western 
weasels. The whole upper lip is brown. 
A much stretched winter skin from Halifax, N. S., decidedly larger than No. 2316, appears 
to belong to this same species. It is pure white, with a strong sulphur yellow tinge beneath, 
