162 U. S. P. R. R. EXP. AND SURVEYS—ZOOLOGY—GENERAL REPORT. 
the characters of the species. The most important fact ascertained is that the winter pelage is — 
entirely white, with a yellowish tinge, except the terminal two-fifths of the tail, which is black, 
about one-third of this on the vertebra, the rest projecting beyond. The species, therefore, 
forms no exception to the general law in regard to change of color in northern ermines. 
Among these specimens, various grades of color, from pure white to brown, may be observed; 
acommon form of change is to have the tail, (except the black tip,) and sometimes the legs, 
white. The middle of the back is the last to change color. 
The species is readily distinguished from the other American weasels by the small size, and 
the tail, which, with the hairs, is rather less than half the body. P. pusillus, nearest to it in 
size, has a considerably shorter tail, with the tip only slightly dusky, not black. 
The Putorius cicognanii is one of the most strongly marked and easily identified American 
species, although not accurately described until this was done by Audubon and Bachman, in 
1842. It was first defined, in 1838, however, by Bonaparte, as quoted above, and although 
he does not give any very accurate description, yet his comparisons with European species are 
such as to leave no doubt that he meant the animal subsequently named P. fuscus by Audubon 
and Bachman. His diagnosis is as follows : : 
“¢ Mustela cicognanii.—M. ruto-cinamomea, subtus flavo-albida; cauda corporis dimidio sub- 
breviori ; apice nigricante.’’ 
The only American species to which this description can apply is that described in the present 
article. Including the entire length of the tail to end of hairs, as the author does, the statement _ 
of ‘‘ tail rather less than half the body,’’ applies exactly. The larger species have the whole 
tail more than half the body, while the smaller P. pusillus has it much less than half the body, 
and the tip is merely dusky, not black. 
There would be no confusion whatever in the case but for the reference by Richardson, in 
Zoology of Beechey’s Voyage, 1839, 10*, of Mustela cicognanii to his M. vulgaris, as given in 
Fauna Boreali-Americana. In this, however, he is clearly in error. Bonaparte, while imposing, 
in Charlesworth’s Magazine, new names on the large ermines described in the “ Fauna,”’ in 
the same article speaks of I. cicognanii as intermediate between I. erminea and boccamela, and 
places the If. vulgaris of Europe after boccamela. He also mentions expressly the distinct black 
tip to the tail, not found in the true Putorius vulgaris, nor its American analogue, P. pusillus, 
described under that name by Richardson. 
The distribution of this species is not well ascertained. The Smithsonian speciméns come 
entirely from Massachusetts, with the exception of one from Illinois. 
Nore.—Just as this article is passing through the press, a series of hunters’ skins of weasels has been received from Dr, 
Gilpin of Halifax, among which are several that agree very well with typical specimens of M. cicognanii from Massachusetts. 
Others again, though considerably larger, preserve the same proportions in the length of the tail, as well as the other charac- 
teristics, and I cannot very well hesitate to extend the supposed limits of size, as well as of geographical distribution, considerably 
beyond those suggested in the preceding paragraphs. The same may be said of skins from Fort Vancouver and Puget Sound, 
as indicated in the list of specimens, though these are more nearly the size of those first described. Still the whole subject is 
one involved in uncertainty, and can only be settled by the examination of many additional specimens from numerous localities, 
accurately measured before skinning. 
