145 Townsend's Shrew Mole
SCALOPS TOWNSENDII.--BACH. [Scapanus townsendii] TOWNSEND'S SHREW-MOLE. [Townsend's Mole] PLATE CXLV.--MALES. S. Magnitudine S. aquatico duplo major, supra rufo-fuscus. Dentibus XLIV. CHARACTERS. Double the size of the common Shrew-Mole, with eight more teeth than that species; dark liver colour. SYNONYMES. COMMON MOLE. Mackenzie's Voyage to the Pacific, &c., p. 314. MOLE. Lewis and Clark, Journey, vol. iii. p. 42. SCALOPS CANADENSIS. Rich., Fauna Boreali Americana, p. 9. SCALOPS TOWNSENDII. Bach., Jour. Acad. Nat. Sci., vol. viii., part 1, p. 58. DESCRIPTION. 2 6-6 4-4 Dental Formula.--Incisive -; Canine ---; Molar --- = 44. 4 6-6 3-3 In the upper jaw the incisors are large, and a third higher than the canine teeth usually termed false molars, which immediately follow them; these are succeeded by three small teeth of a nearly conical shape, increasing in length from the first to the third; the fourth false molar on each side is the smallest; the fifth is a little larger in size, and slightly compressed; the sixth still larger, and has a considerable posterior projection; the four posterior cheek teeth, or true molars, are much larger and higher than the anterior ones; the first of these (which we have called a canine tooth) is rather small, and bilobed, with a small internal tubercle; the second and third are the largest and nearly resemble each other, exhibiting three distinct points, two external and posterior, and one anterior, the external ones being the longest, and the last molar being the smallest, and of a triangular form; in the lower jaw there are two very small incisors in front; next to these are two of a considerably larger size, which, although we have called them incisors, are nearly of the same shape and appearance as those which succeed them. The canine or false molars, six on each side, are nearly the same size, and incline forwards; the three true molars, which succeed, are large, nearly uniform in size, and correspond with those in the upper jaw, although they are smaller. Body, thick and cylindrical, shaped like the Shrew-Mole (Scalops aquaticus); the limbs are short, being concealed by the skin of the body nearly down to the wrist and ankle-joints. Palms, naked, very broad, furnished with moderately long nails which are channelled beneath; tail, rather thick, tapering from the root to the tip, and nearly naked, being very sparingly clothed with short hairs; the vertebrae are equally four sided; fingers, very short, united to the roots of the nails; nails, slightly curved; hind-feet, more slender than the fore-feet, and distinctly webbed to the nails; the feet are thinly clothed above, with short hairs. The whole of the body, both upper and lower surface, presents a velvety appearance. COLOUR. The body is dark liver brown colour above, changing with the light in which it is viewed to silvery or black shades; the hair when blown aside exhibits a grayish-black colour to near the tips, which in some of the points are white, others brown black, producing the changeable colours above described. One of the specimens which we have seen--the one figured in our plate--has a whitish-yellow stripe about two lines wide, running in a somewhat irregular line along the under surface of the body to within an inch and a half of the insertion of the tail; there is also a white streak commencing on the forehead, spreading over the snout and around the edges of the mouth and lower jaws. The teeth are white; feet, point of nose, and tail, flesh colour; nails, light brown. DIMENSIONS. Inches. Lines. Length of head and body, . . . . . . 8 6 Length of tail, . . . . . . . . . 1 6 Breadth of palm,. . . . . . . . . 0 7 HABITS. We were informed by NUTTALL and TOWNSEND, who mistook this species for our common Shrew-Mole (Scalops aquaticus), that they dug and formed galleries, and threw up little mounds of earth precisely in the manner of that animal. They are well known to the farmers and settlers in the valleys of Oregon, as they traverse their fields and gardens, cutting up the ground in some places to an injurious extent. GEOGRAPHICAL DISTRIBUTION. This species is found in considerable abundance near the banks of the Columbia and other rivers in Oregon, where our specimens were obtained. We are unable to say what is the northern limit of this animal. It has not yet been found on the eastern side of the Rocky Mountains, and we have not been able to determine positively that it exists in California but we have little doubt that it is the most common Shrew-Mole on the Pacific side of the North American continent, where our common species (Scalops aquaticus) does not appear to have been discovered. GENERAL REMARKS. Sir JOHN RICHARDSON, who first described this animal from a specimen preserved in the museum of the Hon. Hudson's Bay Company, obtained by Mr. DAVID DOUGLAS, does not seem to have made a comparison between this Mole and our common Atlantic species. HARLAN had described the skull of the species which we have since described and figured as Scalops Brewerii, having forty-four teeth, and another which had thirty-six. RICHARDSON was thus induced to suppose that authors had varied in their descriptions of the Scalops from their having mentioned edentate spaces between the incisors and grinders, and had consequently described the young in those specimens which had only thirty-six teeth. The young, however, of our common aquaticus (or as CUVIER has called it, Scalops Canadensis) has only thirty teeth, the adult thirty-six, whilst the present species has forty-four. On our pointing out to Sir JOHN RICHARDSON these particulars, he expressed himself gratified to have an opportunity of correcting the error into which he had inadvertently fallen.