142 The Camas Rat
PSEUDOSTOMA BOREALIS.---RICH. MSS. [Thomomys bulbivorus] THE CAMAS RAT. [Camas Pocket Gopher] PLATE CXLII.---MALE, FEMALE, and YOUNG. P. Ex cinereo fulvus, cauda longa pilosa; P. bursario minor, et gracilior, dentibus unguibusque minoribus. CHARACTERS. Smaller and of more delicate form than Pseudostoma bursarius, and teeth and claws much smaller. Tail, long, and clothed with hair. Colour, pale yellowish-gray. SYNONYMES. GEOMYS BOREALIS. Rich., MSS. PSEUDOSTOMA BOREALIS. Bach., Jour. Acad. Nat. Sciences Philadelphia, vol. vii, part 1, p. 103. GEOMYS TOWNSENDII. Rich., MSS. DESCRIPTION. Head, of moderate size; ears, consisting of a small round opening margined by an elevated ridge, the highest portion of which is the posterior part, and is about one line in height. The ears not hidden by the fur, but distinctly visible. Body, moderately thick; claws of the fore-feet, slender and rather long; incisors, rather long (but not large for the genus); the upper ones have each a slight longitudinal groove situated close to the inner margin. Tip of nose, naked; feet, bare beneath; inner toe of fore-feet, rather short, outer next in length, middle longest, and the toes on either side of the central one about equal; there is a long brush of stiff white hairs on the inner side of the inner toe. On the hind-feet the central toe is longest, outer toes equal and short. Tail, hairy. COLOUR. General colour, pale gray, the upper parts more or less washed with yellow; inside of pouches, under surface of body, feet, and tail, white. Hairs of the body, dark slate colour at the roots. There is a dusky spot behind the ears; incisors, yellow; claws, white; tail, above, grayish, tinged with yellow. DIMENSIONS. Inches. Lines. From nose to root of tail,. . . . . . 7 6 Tail,. . . . . . . . . . . . . 2 0 Tarsus and claws,. . . . . . . . . 1 1 1/2 Central claw of fore-foot,. . . . . . 0 5 Nose to ear, . . . . . . . . . . 1 6 1/2 The above description was made from three specimens of this pouched Sand-rat, obtained by the late Mr. TOWNSEND, on the Columbia river, two of which appeared to be in summer pelage, and the third in its autumnal coat. Description of another specimen sent by Mr. TOWNSEND, marked in RICHARDSON's MSS. as Geomys Townsendii: Form and size of the animal, nearly the same as in the specimens just described, with the exception of the tail, which is considerably longer. General colour, very pale gray above, with a faint yellowish wash; end of nose, dusky gray; under parts, grayish-white; chin, pure white; tail and feet, white, the former grayish above. Hairs of the back, very pale gray at the roots, pale yellow near the tips, the extreme points cinereous. Teeth, yellowish-white; upper incisors, with a faint groove near the internal margin. Claws and fore-feet, moderate white. DIMENSIONS. Inches. Lines. From nose to tail, . . . . . . . . 7 6 Tail,. . . . . . . . . . . . . 2 9 Tarsus, . . . . . . . . . . . . 1 3 1/2 Central claw of fore-foot,. . . . . . 0 5 Nose to ear, . . . . . . . . . . 1 5 HABITS. The Camas Rat derives its name, according to RICHARDSON, from its fondness for the bulbous root of the quamash or camas plant (Scilla esculenta). Like all the pouched Rats of America, it feeds upon nuts, roots, seeds, and grasses, and makes burrows, extending long distances, but not very far beneath the surface of the ground, throwing up mole-hills in places as it comes to the surface. These animals are generally found to be in a certain degree gregarious, or at least a good many of them inhabiting the same locality, and more or less associated together; and are said to be very common on the plains of the Multnomah river. Mr. DOUGLAS informed Sir JOHN RICHARDSON that they may be easily snared in the summer. We believe that some of the Indians of those parts of Oregon in which this burrowing Rat exists eat them, but have no information concerning the peculiarities they exhibit, the number of young they produce at a time, or the depredations they commit on the fields and gardens of the settlers. In the Fauna Boreali Americana (p. 206), this pouched Rat (if we are not mistaken), is given as Diplostoma bulbivorum--Camas Rat--and under the impression that that name applies to our present animal, we have made the above remarks in relation to it. GEOGRAPHICAL DISTRIBUTION. Specimens were obtained both by DOUGLAS and DRUMMOND, about the same period of time, in the vicinity of the Columbia river in Oregon. GENERAL REMARKS. On a visit to Europe we carried with us three specimens of pouched Sand-Rats, which we regarded as belonging to the same species, but being male, female, and young. Our object was to compare them with specimens taken from this country at the north and west by RICHARDSON, DOUGLAS, DRUMMOND, and other naturalists. RICHARDSON kindly showed us a specimen brought from the Columbia river by DOUGLAS, which, as we thought, appeared to be of the same species as our own. As he was then preparing a monograph of this perplexing genus, we requested him to describe the species, and add it to his monograph; he consequently gave it the above name. He however called another specimen which we had carried with us, Geomys Townsendii. We think his monograph was never published. We have united what he considered two species--Geomys Borealis and G. Townsendii--into one, having added the latter as a synonyme; and we have rejected Diplostoma as a genus, not only because we conceive the characters on which it is founded to be the result of an unnatural disposition of the pouches in the dried skins, but for the reason mentioned above viz., that we consider the so-called Diplostoma bulbivorum to be identical with the animal we have just described as Pseudostoma borealis, although the description given by RICHARDSON has apparently no reference to the latter, but on the contrary describes his Diplostoma as having the true mouth vertical (?). He says: "The lips, which in fact are right and left, and not upper and under," &c. Besides, in the beginning of his article he mentions that the skull is wanting. We think we may therefore reasonably presume, that although the skin had been so twisted and disfigured by putting it into an unnatural form that the appellation which Mr. DOUGLAS gave it, as "the animal known on the banks of the Columbia by the name of the Camas Rat," did not seem to apply to it, we shall be right in rejecting both the generic and specific names given by our friend Sir JOHN RICHARDSON to so very imperfect a specimen, and in believing that the skin was in reality (although much injured and distorted) nothing but the Camas Rat, as DOUGLAS called it.