168 U. 8. 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 vertebrae, which, in fact, are only one-fourth the length of head and 



body. In P. noveboracensis, on the other hand, the vertebrae, 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. I am 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 vertebrae, while in the other the tip of the vertebrae 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. ^y* 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 vertebrae, and from P. erminea in possessing twenty-one caudal vertebrae instead of 



nineteen three more vertebrae in all. The caudal vertebrae, applied along the back, extend 



from their base to the first dorsal vertebrae. Skeletons of P. vison and P. frenata, show but 



three sacral vertebrae, 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. 



