MAMMALIA. 211
(66.] 1 . A p l o d o n t ia l e p o r in a . (Richardson.) The Sewellel*
SewelleL L ewis and Clark,, vol. iii. p. 39. ,
Anisonyx ? rufa. Raftnesgi^e-Smaltz. Desmarest, Mamm., p. 330, m notis.
Arctomys rufa. Harlan, Fauna, p. 308. Gr if f it h ’s Anim. Kingdom, vol. v. p 245. sp. 636.
'Marmot, No. 17. Hudson’s B at Museum.
Aplodontia leporina. R ic h a b d s o n , Zool .J w m . January, 1829. No. 15. p. 335.
Plate xviii C. Fig. 7 to 14.
D E S C R I P T IO N . .
Form.—The Sewellel stands very low on its legs, and has a short thick body like that of a
rabbit, with a rather large head. The nose is thick and obtuse, and is covered with a dense
coat of very short fur. The nostrils are like those of a rat, small and roundish, and are
separated by a narrow furrowed septum, but the fur comes close to their margins. The
mouth is rather small, considering the size of the incisors, the lips are thick, clothed with
stiff hairs, and a stiff brush of white hair projects into the mouth from the upper lip, near
its union with the lower one. Whiskers very strong, longer than the head, partly black,,
partly white. There are also some long stiff hairs over the eye and on the cheek. The eye
is very small, the opening between the eyelids not exceeding two lines in length. The.
external ear strongly resembles the human one in form. I t rises about four lines above the
auditory opening, has a small fold of the anterior part of its base inwards, and is prolonged
posteriorly and beneath the opening in form of a narrow thick margin representing the lobe
and anti-tragus. There are also folds and eminences in the concavity of the auricle, such as
exist in the human ear. The whole of the ear is clothed with a very short, close and fine
coat of pale hairs, and on its inner side there are some longer and darker ones, which
project beyond its margin.
• The stump of the tail is scarcely half an inch long, and has a slender cylindrical form. It
is covered with fur of the same'colour and length with that od the rfeighbouring parts, and is
scarcely perceptible, so that the animal on a cursory view might be considered to be tail-less.
■ The legs are very short, and are covered down to the wrists and heels with fur similar to
that on the body. A little above the wrist joint, on the inner .side, there is a small tuft of
stiff white hairs. The feet are shaped somewhat like those of a marmot.
Fore-feet.—.The palms and under surfaces of the toes are naked, There are three small
callous eminences,at the root of the toes, disposed as in the marmots, one of them being
common to the two middle toes, one proper to the fore-toe, and the third to the little toe.
There is a large prominent callus at the root of the thumb, and one nearly of the same size
l E i