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recognized species of American Ermines, P. noveboracensis, De Kay, P. 
rickardsont, Bonaparte (=agilis Aud. & Bach.), and P. cicognani of Bona- 
parte (= fuscus A. & B.), concludes that the American Ermines are of 
two forms in size alone, and these grade insensibly into each other; also,. 
that no question of coloration, stoutness of body, shape of ear, furriness of 
feet, character of pelage, can be considered with reference to Specific va- 
riation, these details depending on fortuitous circumstances of sex, age, 
season and locality, as merely normal individual variability ; moreover 
that within certain defined limits neither the length of the animal, of 
the tail absolutely or relatively to the body, nor length of the black por- 
tion absolutely or relatively to length of tail, have any value in specific 
diagnosis. 
Description of Haxternal Characters—The extreme length, cylindrical 
body, shortness of the limbs, exceptionally long neck, suggests a group 
of carnivores, fitly called “vermiform”; these features, taken with the 
low forehead, flat, triangular head, bent forward upon the uplifted and 
outstretched neck, and small, penetrating eyes full of cunning, suggests 
the serpent almost as fully as they do the quadruped. 
The greatest circumference of the body is little more than half its 
length; the head is shorter than the neck, bulged at the sides by the 
masses of temporal and masseteric muscles; the head, across the ears, is 
two-thirds its length; the small eyes, glittering with changing hues, are 
midway of the nose and ear; the nostrils are small and circular ; the gape of 
the thin-lipped mouth extends to below the eyes; the ears are high above 
the fur, rounded, furred inside and out; the whiskers are few, the longest 
exceeding the head; a few siender bristles grow over the eye and on the 
cheek. The limhs are stout, tapering to the wrist and ankle; the digits 
are all clawed, the claws sharp, slightly curved, and moderately stout, 
adapted for climbing, but not effective in the chase; the feet are densely | 
furred or not, according to the season and latitude; the foot is so densely 
hairy, in boreal specimens, that, as in the Hare, or Ptarmigan, the palmar 
tubercles are invisible; the pads are ten on each foot, under each toe are 
(5), four palmar (9), and one at the wrist (10); these may be readily 
seen in summer or southern specimens. The extremely variable tail is 
furred throughout, and has a terminal pencil of black hairs. 
As to its fur, like that of its group, it increases in softness, fineness, 
and density toward the north, and in winter in all latitudes. In the 
summer, and southward, it is thinner, stiffer, and harsh from admixture 
of long, bristly hairs. In its summer dress, the Hrmine illustrates the 
‘bicolor” pattern, the upper parts ranging from a uniform dull yellow- 
