PUTORIUS PUSILLUS.--Dekay.
                               [Mustela nivalis]

                               THE SMALL WEASEL.
                                 [Least Weasel]

                                  PLATE LXIV.


     P. erminia tertia parti minore; cauda breviuscula. Supra rufo-fuscus subtus
albus.

                               CHARACTERS.

     A third smaller than the Ermine; tail rather short; Colour, brown above
while beneath.


                                   SYNONYMES.

     MUSTELA (PUTORIUS) VULGARIS, Bach., Fauna Bor. Am., vol. i., p. 45.
     P. VULGARIS, Emmons, Mass. Report, 1840, p. 44.
     MUSTELA PUSILLA, Dekay, Nat. Hist. N. Y., p. 34.


                                  DESCRIPTION.

     This is much the smallest of all our species of Weasel, if we are to judge
from two specimens that are in our possession, which appear to be full grown.
The tail is about one-fourth the length of the body, and is a little longer than
that of the common Weasel (M. Vulgaris) of Europe.  It is, however, a still
smaller animal, and differs from it in several other particulars:  its ears are
less broad, its feet smaller, the colour on the back is a shade darker, the
white on the under surface extends much farther along the sides, towards the
back, and the dividing line between the colours on the upper and lower surface
is more distinct.  The head is small, neck slender, and the body vermiform.
Whiskers the length of the head, ears very small, toes and nails slender,
covered with hairs.


                                    COLOUR.

     We are inclined to believe that this species does not become white in
winter.  We kept a small weasel alive throughout a winter in our boyhood, but
cannot now decide whether it was this species or another, (P. Fuscus,) which we
will describe in our next volume.  That species underwent no change in winter.
It is more glossy than the ermine in summer pelage and a shade paler in colour.
It is light yellowish brown on the head, neck, and the whole of the upper
surface; this colour prevails on the outer portions of the fore-legs to near the
feet, the outer sur face of the hind-legs, the rump, and the whole of the tail,
which is not tipped with black as in the ermine.  The white on the under
surface, commences on the upper lips and extends along the neck, inner surface
of the legs, rises high up along the sides, including the outer and inner
surfaces of the feet.  The moustaches are white and black, the former colour
predominating.


                                  DIMENSIONS.
                                                                   Inches.
     Length from point of nose to root of tail,.  .  .  .  .  .  .  7
     Head and neck, .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  3
     Tail (vertebrae), .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  2
     Tail including fur,  .  .  .  .  .  .  .  .  .  .  .  .  .  .  2 1/8


                                     HABITS

     From the form and structure of this species, we might naturally presume
that it possesses all the habits of the ermine.  It feeds on insects, eggs of
birds, and mice, but from its diminutive size we are led to suppose that it is
not mischievous in the poultry house, and would scarcely venture to attack a
full-grown Norway rat.


                           GEOGRAPHICAL DISTRIBUTION.

     The specimens from which our descriptions were made, wore obtained in the
State of New-York, one at the Catskills, and the other at Long Island.  If it
should prove to be the species we once had in captivity, it exists also in the
northern part of New-York, where we captured it.  RICHARDSON asserts that it
exists as far to the North as the Saskatchewan river, and Captain Bayfield
obtained specimens at Lake Superior.


                                GENERAL REMARKS.

     Sir John RICHARDSON states that this species, like the ermine, becomes
white in winter in the fur countries.  We are disposed to believe that this is
not the case in the latitude of New-York.  This fact, however, is no evidence
that the species in those widely separated localities are different.  The ermine
in the northern part of Virginia seldom undergoes a perfect change, and in
Carolina remains brown throughout the whole year.  Sir John RICHARDSON states
(p. 45) that the specimens presented to the Zoological Society by Capt.
BAYFIELD, agreed in all respects with the common weasel of Europe.  We, however,
examined these specimens and compared them with the European weasel, and found
no difficulty in discovering characters by which the species are separated.  We
have an indistinct recollection that the prince of Musignano named the specimen
in the Zoological Society; but as be did not, as far as we know, describe it, we
have, according to our views on these subjects, assigned to Dr. DEKAY the credit
of the specific name.