123 The Sewell
APLODONTIA LEPORINA.--RICH. [Aplodontia rufa] THE SEWELLEL. [Mountain Beaver] PLATE CXXIII.--MALE. A. Fuscescens, magnitudine Leporis Sylvatici, corpore brevi robusto, capite magno, cauda brevissima.
CHARACTERS. Size of the gray rabbit (Lepus Sylvaticus). Body, short and thick; head, large; tail, very short. Colour, brownish. SYNONYMES. SEWELLEL. Lewis and Clark, vol. iii. p. 39. ARCTOMYS RUFA. Harlan, Fauna, p. 308. ARCTOMYS RUFA. Griffith, Cuv. Animal Kingdom, vol. v. p. 245, species 636. APLODONTIA LEPORINA. Rich, Zool. Jour., No. 15, p. 335. January, 1829. APLODONTIA LEPORINA.--SEWELLEL. Rich, Fauna Boreali Americana, p. 211, pl. 18 c, figs. 7-14, cranium, &c. DESCRIPTION. Body, short, thick, and heavy, nearly reaching the ground; legs, short; head, large; nose, thick and blunt, densely covered with hair to the nostrils, which are small and separated by a narrow furrowed septum concealed by the hair. Mouth, rather small; incisors, large and strong; lips, thick, and clothed with rigid hairs; a brush of white hair projects into the mouth from the upper lip near its union with the lower one; whiskers, strong, and longer than the head; a few stiff hairs over the eyes, on the cheeks, and on the outer sides of the fore-legs; the eye is very small; the external ear rises rather far back, and is short and rounded; it rises about four lines above the auditory opening, has a small fold of the anterior part of its base inwards, together with a narrow thick margin, representing a lobe. There are also folds and eminences in the cavity of the auricle; the ear is clothed on the outer surface with short and fine hairs, and on the inner, with hairs a little longer; tail, short, slender, and cylindrical, and almost concealed by the hair of the rump; legs, covered down to the wrists and heels with short fur; feet, shaped like those of the marmots; palms and under surfaces of the fore feet, naked; there are three small callous eminences at the roots of the toes, disposed as in the marmots, one of them being common to the two middle toes, one proper to the third toe, and the other to the little toe. At the root of the thumb there is a large prominent callosity, and on the opposite side of the palm another one nearly the same size; the thumb is of sufficient length to be used in grasping, and is terminated by a smooth rounded nail; claws, large and very much compressed, slightly arched above, and nearly straight below; hind feet, more slender than the fore feet, and their claws one half smaller, rather more arched, and less compressed; soles, longer than the palms, and naked to the heel; they are furnished with four callous eminences situated at the roots of the toes, and two placed farther back, all more conspicuous than those on the hind feet of the spermophiles of America. The hair is soft, and somewhat resembles the finer fur of the muskrat; the under fur is soft, tolerably dense, and about half an inch long; the longer hairs are not sufficiently numerous to conceal the under fur. The hair on the feet only reaches to the roots of the claws, which are naked. A specimen of a young Sewellel brought by DOUGLAS and examined by RICHARDSON, in which the dentition was the same as in the adult, exhibited a new set of molar teeth, which had destroyed the greater part of the substance of the old teeth, leaving merely a long process before and another behind in each socket, resembling fangs. COLOUR. Incisors, yellow; claws, horn colour; general hue of the back, brownish, the long scattered hairs being tipped with black; belly, grayish, with many of the long hairs tipped with white; nose, nearly the colour of the back; lips, whitish; in some specimens there is a spot of pure white on the throat. The hairs on the back, when blown aside, exhibit a grayish colour from the roots to the tips, which are brown. DIMENSIONS. Inches. Lines. Length of head and body, . . . . . . 14 0 Length of tail, . . . . . . . . . 0 6 Wrist joint to end of middle claw, . . . 1 9 Middle claw, . . . . . . . . . . 0 6 Length of head, . . . . . . . . . 3 4 HABITS. LEWIS and CLARK, who discovered this species during their journey across the Rocky Mountains to the Pacific, give us the following account of it: "Sewellel is a name given by the natives to a small animal found in the timbered country on this coast. It is more abundant in the neighbourhood of the great falls and rapids of the Columbia than on the coast. The natives make great use of the skins of this animal in forming their robes, which they dress with the fur on, and attach them together with the sinews of the elk or deer. The skin when dressed is from fourteen to eighteen inches long, and from seven to nine in width: the tail is always separated from the skin by the natives when making their robes." "This animal mounts a tree, and burrows in the ground, precisely like a squirrel. The ears are short, thin, and pointed, and covered with a fine short hair, of a uniform reddish-brown; the bottom or the base of the long hairs, which exceed the fur but little in length, as well as the fur itself, are of a dark colour next to the skin for two thirds of the length of this animal; the fur and hair are very fine, short, thickly set, and silky; the ends of the fur and tip of the hair are of a reddish-brown, and that colour predominates in the usual appearance of the animal. Captain LEWIS offered considerable rewards to the Indians, but was never able to procure one of these animals alive." Mr. DOUGLAS gave Dr. RICHARDSON an Indian blanket or robe, formed by sewing the skins of the Sewellel together. This robe contained twenty-seven skins, selected when the fur was in fine order. They are described by Dr. RICHARDSON as all having the long hairs so numerous as to hide the wool or down at their roots, and their points have a very high lustre. The doctor appears to think there were skins of two species of Sewellel in this robe. We did not hear of this animal ever being found to the east of the Rocky Mountains. Our figure was drawn from a fine specimen in London. We are inclined to think from the form of the Sewellel that it is a great digger; but LEWIS' account of its mounting a tree seems to us to require some modification; the Maryland marmot, to which it is somewhat allied in form and in the shape of its claws, when hard pressed will mount a tree for a little distance to avoid the pursuit of a dog, but is very awkward and soon descends; we presume the climbing properties of the Sewellel can scarcely be greater than those of the marmot. From the number of mammae exhibited in the female, we conclude that it produces five or six young at a tune, and from the nature of the animal, these are probably brought forth, like those of the marmots, in nests within their burrows. GEOGRAPHICAL DISTRIBUTION. This singular species has been observed on the western slopes of the Rocky Mountains, in the valleys and plains of the Columbia, at Nisqually, and at Puget's sound, where it is said to be a common animal. It has also been procured in California. GENERAL REMARKS. The history of this species, of which, however, little is known, is somewhat curious. LEWIS and CLARK appear to have been the only individuals who gave any notice of it until a very recent period, when DOUGLAS procured a specimen, and RICHARDSON gave a scientific account of the animal. The account LEWIS and CLARK gave dates back to 1804, and we have given the whole of their article above; these travellers, however, brought no specimens. After the journal of their adventurous expedition was published, RAFINESQUE ventured to give to the Sewellel the name of Anysonix Rufa, HARLAN named it Arctomys Rufa, and GRIFFITH introduced it into the animal kingdom under the same name; in 1829, RICHARDSON obtained a specimen, and the Sewellel was now for the first time examined by a naturalist. Believing that no one who had not seen or examined a species had a right to bestow a specific name, RICHARDSON rejected both the generic and specific names of previous writers, established for it a new genus, and gave it the name it now bears, and which it will doubtless preserve in our systems of Zoology. There are two specimens of this animal in the Patent Office at Washington city, which were procured by the Exploring Expedition under command of Captain WILKES. We were recently politely refused permission to take them out of the glass case (in which they have for some time past remained) to examine their fur and measure them. We will not take the trouble to make any further remarks on this subject, as we have in a note at page 211 of our second volume mentioned the obstructions thrown in our way by the directors of the National Institute at Washington, the officers in charge of the collection informing us that by high authority the specimens were "tabooed."