168 U. S. P. R. R. EXP. AND SURVEYS—ZOOLOGY—GENERAL REPORT. 
the most striking is to be found in the tail, which (including the hairs) in P. erminea is about 
as long, or a little longer, than half the body. The hairs on the extremity are very long and 
bushy, measuring from one inch and three-quarters to two inches and a half, and being nearly 
two-thirds as long as the tail vertebra, which, in fact, are only one-fourth the length of head and 
body. In P. noveboracensis, on the other hand, the vertebrz, exclusive of the hairs, are nearly 
half the length of the body; the projection beyond the tip, from one inch to one inch and a half, 
or about one-fourth of the length of the vertebral portion. Iam unable to make any actual 
comparison of the feet, owing to the shrivelled condition of all the specimens on hand, The 
ears of the American species appear decidedly larger. 'The naked portion of the nose is larger 
also, and the septum is broader and descends further towards the mouth. The coloration again 
is decidedly different, in the much greater extension of the light colors over the lower parts in 
P.erminea. Here the line of separation is higher up on the flanks, while the inside of all the 
limbs, the entire feet, and the under surface of the tail, including the region of the groin and 
nates are yellowish white. In the American species the entire limbs, except the upper portion 
of their interior surfaces, the nates, groin, and entire tail, except at the tip, are chestnut brown, 
like the back. The black of the tail begins more abruptly in P. erminea, at a short distance 
before the end of the vertebre,‘while in the other the tip of the vertebre falls in about the 
middle portion. InP. erminea again, the dividing line of color passes high up on the cheek, nearly 
bisecting the side of the head, and passing but a short distance below the orbit, (about half its 
diameter,) the whole upper lip being white. In the American species this line is much lower 
down or on a level with the angle of the mouth, only a small edging of the upper lip being 
white. I have not noticed in any American specimen the white edging of the ears seen in 
Swedish specimens. This may, however, be merely an incipient change of coloration. The 
winter dresses differ in the greater comparative extent of the black tip to the tail in P. erminea. 
The skeleton of No. az; from Carlisle, has of vertebrae: seven cervical, fourteen dorsal, six 
lumbar, four sacral, and twenty-one caudal—fifty-two. It differs from most weasels in having 
four sacral vertebree, and from P. erminea in possessing twenty-one caudal vertebrie instead of 
nineteen—three more vertebre in all. The caudal vertebrae, applied along the back, extend 
from their base to the first dorsal vertebra. “Skeletons of P. vison and P. frenata, show but 
three sacral vertebrz, as in most species, with the probably necessary assignment of all the far 
western large ermine weasels of America to the Putorius longicauda, the range of Putorius 
noveboracensis becomes much more limited than heretofore supposed, especially if the northern 
one be the Putorius richardsonii. Thus far we cannot trace it north of Massachusetts nor west 
of Wisconsin.. Fort Smith, Arkansas, and Pennsylvania, are the more southern localities. 
It probably extends through most of the southern and southwestern States. 
I have seen no pure white skins of this weasel, and do not feel sure that it changes except in 
the most northern portions of the United States. 
I do not consider it as by any means certain that Dekay in his article on P. noveboracensis 
does not describe, at least in part, the P. richardsonii. The figure of the winter specimen is 
almost exactly this last species. The description and figure of the summer specimen give no 
indications of any white border to the upper lip. If this be really a character of P. richardsonii, 
it will settle the question. In the necessary uncertainty it will be best, however, to retain and 
strengthen the name of Dekay, rather than to reduce it to a synonym by the application of a 
new one. 
