DESCRIPTION
Of a full grown but young individual.
Dental formula, incisors, §, canines grinders = 22.
Incisors, much compressed, very strong, and having a deep orange colour on their exterior
surfaces. The first or deciduous grinder is round and very small, the others are precisely
similar in form to the grinders of the Hudson’s Bay squirrel.
Form.—Its head is somewhat narrower and its nose sharper than that of the large gray
American squirrel. Its frontal bone is not so flat between the orbits as that of the Hudson s
Bay squirrel, and has a nearly regular flat elliptical curve from the occipital ridge to the
end of the nose. Its scull is about twice as big as that of a Hudson’s Bay squirrel. Ears
elliptical rounded at the tip, •covered with short fur, and entirely without tufts.
Fur.—The whole fur is black, that on the back being particularly close and having a glossy
hue. When blown aside it appears downy towards the roots, and has a grayish-black colour
without lustre. The fur is much shorter and coarser than that of the gray squirrels. On the
dorsal aspect of the head it is of a shining black colour, without any lighter coloured spots
about the muzzle or behind the ear. On the cheeks and throat it is of a brownish-black.
The tail is clothed with long hair, unmixed with down, except close to the body. The feet
are clothed with a smooth coat of short black hair. The claws are curved, much compressed,
and sharp, exactly resembling those of the gray squirrel. The thumb tubercle is armed with
a rounded nail closely adhering to it. The claws of the hind-feet are somewhat sharper than
the fore ones, but are similar in form and nearly of equal size.
D im e n s io n s
Of the Penetanguisbene Specimen.
Length of the head and body . . 1 3
,, head . , , . 3
„ tail (vertebrae) . . 9
„ tail including fur . . . 1 3
„ palm to the tip of the middle
' fore-claw . . . . 1
,, j third or longest fore-toe and daw 1
lin e s. . I |lcW
0 Length from the thumb to the tip of the middle
0 fore-claw . • • 1
0 „ of the sole, middle hind-toe, and claw 2
0 • > „ middle hind-toe and daw . 1
„ longest daws . • 0
0 „ fur on the back .• • 0
1 fur on the sides of the tail . 2
fur at the end of the tail . -3
38139
66
D im e n s io n s
Of the Scull of the same Spedmen.
Inches. Lines.
Smallest breadth of the os frontis between the orbits . . 0 9
Length of the nasal bones . . • . • . 0 9a
There is a specimen of rather larger dimensions, procured at Fort William, on
Lake Superior, and presented to the Zoological Society by Captain Bayfield. It has
a few white hairs scattered amongst the fur of the body and rather more in the tail,
Lewis and Clark mention their having met with gray squirrels on the
Columbia; but from our ignorance of the species to which they belong, they cannot
be admitted into this work.
[61.] 1. P teromys S a b e in u s . Severn River Flying Squirrel.
G e n u s Pteromys. C u v i e r . Sciuropterus. F. C u v i e r .
Greater Flying-Squirrel. F o r s t e r , Phil. Trans., vol. Ixii. p. 379.
Severn-River Squirrel. P e n n a n t , Hist. Quad., vol. ii. p. 153. Arct. Zool., vol. i. p. 122.
Sciurus Hudsonius. G m e l t n , Sysl., vol. i. p. 153.
Sciurus Siabrinus. Shaw, Zool., vol. ii. pt. i. p. 157-
Pteromys Sabrinus. R ic h a r d s o n , Zool. Journ., No. 12. p. 519, April, 1828.
Pt. {Sabrinus), super ex rubescenti brunneus, cauda planiuscula corpus subcequanti dorsoque concolori, lobulo
mem.brance volitantis rotundato. ' 'i:
Severn River Flying-squirrel, pale reddish-brown above ; tail flattish, nearly as long as the body, and of the
same colour with the back ; flying membrane having a small rounded projection behind the wrist.
This is a very distinct species from the much smaller Assapan, (Pt. volucella)
which is common in the United States. It was first described by Forster, who saw
a specimen brought from Severn River that falls into James’s Bay, and was considered
by him to be the same species with the European flying squirrel, which
it much resembles. I have followed Pennant and Shaw in separating it from
the latter, on account of its longer tail, different coloured fur, and the smallness
of the rounded projection of the flying-membrane behind the wrist.
The Severn River Flying Squirrel does not extend its range further north than
latitude 52° (unless the Rocky Mountain one prove to be only a variety of it.)
Mr. Tod sent me a specimen from Penetanguishene on Lake Huron, and I have
seen others from Moose Factory, at the bottom of James’s Bay.
DESCRIPTION.
Dental formula, incisors f , canines £=?, grinders g = 22.
Head round, nose short and obtuse, covered above with a smooth shining coat of light
gray hair. Incisors nearly even with the end of the nose, anteriorly of a deep orange colour.
Whiskers black, longer than the head. Eyes large, surrounded by a blackish-gray marking
in the fur. Flying-membrane extending from the wrist to the middle of the hind leg, nearly
straight, having only a very slight rounded projection close to the wrist.
The fu r is every where remarkably fine and soft. On the dorsal aspect of the head, body,
and flying-membrane, it is of a deep blackish-gray colour from its roots to its tips, which are
of a pale reddish-brown, and which form the colour of the surface when the fur lies smoothly.
There is no different coloured stripe on the flying-membrane, but the dark colour of the
roots of the fur is more easily seen there. The outer surfaces of the fore and hind-feet are