PTEROMYS SABRINUS.--PENNANT.


                         SEVERN RIVER FLYING-SQUIRREL.
                           [Southern Flying Squirel]

                             PLATE CXLIII.--FIG. 1.


     P. Magnitudine P. volucellum tertia parte excedens; cauda corpore curtiore,
patagio lumbari pone carpum in lobum rotundatum excurrente, colore
flavescente-cano obscuriore inumbrato.


                                  CHARACTERS.

     One third larger than P. volucella; tail, shorter than the body; flying
membrane having a small rounded projection behind the wrist.  Colour, dull
yellow gray, irregularly marked with darker.


                                   SYNONYMES.

     GREATER FLYING-SQUIRREL.  Forster, Philos. Trans., vol. lxii. p. 379.
     SEVERN RIVER FLYING-SQUIRREL.  Pennant, Hist. Quad., vol. ii. p. 153.
     SEVERN RIVER FLYING-SQUIRREL.  Pennant, Arctic Zoology, vol. i. p. 122.
     SCIURUS HUDSONIUS.  Gmel., Syst,, vol. i. p. 153.
     SCIURUS SABRINUS.  Shaw, Zool., vol. ii., part 1, p. 157.
     PTEROMYS SABRINUS.  Rich., Zool. Jour., No. 12, p. 519.
     PTEROMYS SABRINUS.  Rich., F. B. A., p. 193.


                                  DESCRIPTION.

     Head, short and somewhat rounded; nose, short and obtuse; eyes, large;
flying membrane, extending from the wrist to the middle of the hind-leg, nearly
straight, having only a slight rounded projection close to the wrist; tail,
depressed, slightly convex on its upper surface, but quite flat, or even
somewhat concave, beneath; it is broadest about an inch from the body, and then
tapers gradually but very slightly towards the extremity, which is rounded; the
flattened form of the tail, and its distichous arrangement, is given to it in
consequence of the fur on its sides being much longer than that on its upper
surface; the extremities are small; the fore-legs connected with the flying
membrane down to the wrist; the feet are hairy both above and below.  There are
four short toes on the fore-feet, and the claws are small, compressed, curved,
and sharp pointed; under their roots there is a compressed callous space,
projecting from the end of each toe, and there is a callosity in place of a
thumb, armed with a very minute nail.
     There are five hind toes; the claws resemble those of the fore feet, and
are almost concealed by the hair of the toes; the soles are covered with a dense
brush, like the feet of a rabbit or hare.  The fur is soft, long, and silky on
all parts.


                                    COLOUR.

     Incisors, deep orange; whiskers, black; a dark gray marking around the eye.
The hairs on the upper surface of the head and body are of a deep blackish-gray
colour from the roots to near the tips, which are pale reddish-brown, but
distinctly presented only when the fur lies smoothly; on the flying membrane the
colour is a shade darker in consequence of the under colour not being concealed
by the lighter colour of the tips; the outer surfaces of the feet are pale
bluish-gray; the margins of the mouth, sides of the nose, cheeks, and whole
ventral aspect of the body, white, with a tinge of buff under the belly, and
particularly under the flying membrane.  Tail, nearly the colour of the back,
with an intermixture however of black hairs; beneath, it is buff; hair on the
soles, yellowish-white.


                                  DIMENSIONS.

                                            Inches.        Lines.

     Length of head and body,  .  .  .  .  .  8            0
     Tail, including fur,.  .  .  .  .  .  .  5            9
     Height of ear,.  .  .  .  .  .  .  .  .  0            5 1/2
     Heel to end of claw,.  .  .  .  .  .  .  1            5 1/2
     Longest hind-toe and nail,.  .  .  .  .  0            4 3/4
     Fore-toe and nail,  .  .  .  .  .  .  .  0            5


                                    HABITS.

     We found this interesting Flying-Squirrel in abundance at Quebec, and many
of them were offered for sale in the markets of that city during our sojourn
there.  It appears indeed to take the place of the common small Flying-Squirrel
of the United States (P. volucella) in Lower Canada, where we did not observe
the latter east of Montreal.
     We heard that one of these pretty animals was caught alive by a soldier who
saw it on the plains of Abraham, and ran it down.
     A brood of young of this species, along with the mother was kept in
confinement by an acquaintance of ours, for about four months, and the little
ones, five in number, were suckled in the following manner:  the younglings
stood on the ground floor of the cage, whilst the mother hung her body
downwards, and secured herself from falling by clinging to the perch immediately
above her head by her fore-feet.  This was observed every day, and some days as
frequently as eight or ten times.
     This brood was procured as follows:  a piece of partially cleared wood
having been set on fire, the labourers saw the Flying-Squirrel start from a
hollow stump with a young one in her mouth, and watched the place where she
deposited it, in another stump at a little distance.  The mother returned to her
nest, and took away another and another in succession, until all were removed,
when the wood-cutters went to the abode now occupied by the affectionate animal,
and caught her already singed by the fire, and her five young unscathed.
     After some time a pair of the young were given away to a friend.  The three
remaining ones, as well as the mother, were killed in the following manner:
     The cage containing them was hung near the window, and one night during the
darkness, a rat, or rats (mus decumanus), caught hold of the three young through
the bars, and ate off all their flesh, leaving the skins almost entire, and the
heads remaining inside the bars.  The mother had had her thigh broken and her
flesh eaten from the bone, and yet this good parent was so affectionately
attached to her brood that when she was found in this pitiable condition in the
morning, she was clinging to her offspring, and trying to nurse them as if they
had still been alive.
     This species is said to bear a considerable resemblance to the European
Flying-Squirrel.  It was first described by FORSTER, who not having
distinguished it from the European animal, PENNANT stands as its discoverer.
     We did not observe any of these Flying-Squirrels on the borders of the
Yellow Stone or Upper Missouri, and have no further information as to their
habits.
     In our first volume (pp. 134, 135), we mentioned that Sir JOHN RICHARDSON
speaks of a Flying-Squirrel which he considered a variety of P. sabrinus, and
called var. B. alpinus.  We then remarked that we hoped to be able to identify
that variety when presenting an account of the habits of P. sabrinus, and in our
next, article shall have the pleasure of doing so, having named it P. alpinus.


                           GEOGRAPHICAL DISTRIBUTION.

     The northern range of this species is about latitude 52 degrees; it has
been captured on the shores of Lake Huron, and at the bottom of James Bay, at
Moose Factory.  We obtained specimens in the neighbourhood of Quebec, where in
the autumn they were exceedingly abundant.
     We have not a doubt it is found in the United States south of the river St.
Lawrence, but at present have no evidence to that effect.  It does not appear to
exist on either slope of the Rocky Mountains, nor have we in fact been able to
find any of our smaller Rodentia of the Atlantic States in those regions.


                                GENERAL REMARKS.

     As long as only two species of Flying-Squirrel were known in North
America--the present species (P. sabrinus) and the little P. volucella--there
was no difficulty in deciding on the species, but since others have been
discovered in the far west, the task of separating and defining them has become
very perplexing.  We will however endeavour, in our next article, in which we
shall describe P. alpinus, to point out those characters which may enable
naturalists to distinguish the closely allied species.