24 Four Striped Ground Squirrel
TAMIAS QUADRIVITTATUS.--SAY. [Eutomis quadriuittatus] FOUR-STRIPED GROUND-SQUIRREL. [Colorado chipmunk] PLATE XXV.--MALE, FEMALE, AND YOUNG. T. striis quinque sub nigris longitudinalibus, cum quatuor sub albidis dorso alternatum distributis; corpora magnitudine T. Lysteri minore; lateribus rufo fuscis, ventre albo. CHARACTERS. Smaller than Tamias Lysteri; five dark brown stripes and four light-coloured stripes occupying the whole back; sides, reddish-brown; underneath, white. SYNONYMES. SCIURUS QUADRIVITTATUS, Say, Long's Expedition, vol. v., p. 349. SCIURUS QUADRIVITTATUS, Griffith, Animal Kingdom, vol. v., No. 665. SCIURUS QUADRIVITTATUS, Harlan, Fauna; p. 180. SCIURUS QUADRIVITTATUS, Godman, vol. ii., p. 137. SCIURUS (TAMIAS) QUADRIVITTATUS, Rich., Zool. Journ., No. 12, p. 519, April, 1828; Fauna Boreali Americana, p. 184, pl. 16. TAMIAS MINIMUS, Bach., Journ. Acad. Nat. Sc. Phila., vol. viii., part 1, Young. DESCRIPTION. Head, of moderate size; nose, tapering, but not very sharp. The mouth recedes very much, (as in all the other species of Tamias;) cheek-pouches, of moderate size; whiskers, about the length of the head; eye, small; ears, erect, of moderate length, clothed on both surfaces with very short hairs; body, rather slender; fore-feet, with four toes and a small thumb, armed with an obtuse nail; palms, naked; claws, compressed, and curved like those of Tamias Lysteri. Hind-feet, with five slender toes; soles, covered with short hairs for three-fourths of their length; tail, long, narrow and sub-distichous. COLOUR. Forehead, dark-brown, with a few whitish hairs interspersed; a narow black line from the nostril to the corner of the eye; above and beneath the eye, a line of white, which continues downward to the point of the nose. A dark-brown dorsal line, commencing behind the ears, continues along the back to the insertion of the tail; another line, which is not quite so dark, begins at each shoulder and ends on the buttocks, near the tail; on each flank there is another shorter and broader line, which runs along the sides to near the haunches; on each side of the dorsal line there is a light-coloured stripe running down to near the insertion of the tail. The outer brown stripes are also separated by a line of yellowish-white; thus the whole back is covered by five dark and four pale lines. From the neck a broad line of reddish-brown extends along the sides, terminating at the hips; feet, light yellowish-brown; under surface of the body, and inner surface of the legs, grayish-white. The tail, which is slightly distichous, is composed of hairs yellowish-brown at the roots, then dark-brown, and tipped with reddish-brown; on its under surface they are reddish-brown, then black for a narrow space, and reddish-brown at the tips. DIMENSIONS. A fine Male (killed Aug. 19th, 1843, on the Upper Missouri river.) Inches. Nose to anterior canthus . . . . . . . . . . . . 1/2 Nose to opening of ear . . . . . . . . . . . . . 1 1/8 Height of ear . . . . . . . . . . . . . . . . 1/2 Width of ear . . . . . . . . . . . . . . . . 7/16 Between centre of eyes . . . . . . . . . . . . . 5/8 Length of head and body. . . . . . . . . . . . . 4 3/8 Tail (vertebrae) . . . . . . . . . . . . . . . 3 1/4 Tail to end of hair . . . . . . . . . . . . . . 4 1/4 Heel to end of hind-claws . . . . . . . . . . . . 1 1/16 Palm and fore-feet to claws . . . . . . . . . . . 1 1/16 Weight 4 oz. HABITS. This pretty little species was discovered by Mr. SAY, during Colonel Long's expedition. Mr. SAY does not however appear to have seen much of its habits, and gives us but the following short account of them:-- "It does not seem to ascend trees by choice, but nestles in holes, and on the edges of rocks. We did not observe it to have cheek-pouches. Its nest is composed of a most extraordinary quantity of the burrs of the cactus, and their branches, and other portions of the large upright cactus, and small branches of pine trees and other vegetable productions, sufficient in some instances to fill an ordinary cart. What the object of so great and apparently so superfluous an assemblage of rubbish may be we are at a loss to conjecture; nor do we know what peculiarly dangerous enemy it may be intended to exclude by so much labour. Their principal food, at least at this season, is the seeds of the pine, which they readily extract from the cones." We met with this species as we were descending the Upper Missouri river in 1843; we saw it first on a tree; afterwards we procured both old and young, among the sandy gulleys and clay cliffs on the sides of the ravines near one of our encampments. These Ground Squirrels ascend trees when at hand and offering them either shelter or food, and seem to be quite as agile as the common species Tamias Lysteri. Dr. RICHARDSON, who found this Ground Squirrel during his long and laborious journeyings across our great continent, says of it-- "It is an exceedingly active little animal, and very industrious in storing up provisions, being very generally observed with its pouches full of the seeds of leguminous plants, bents and grasses. It is most common in dry sandy spots, where there is much underwood, and is often seen in the summer, among the branches of willows and low bushes. It is a lively restless animal, troublesome to the hunter, and often provoking him to destroy it, by the angry chirruping noise that it makes on his approach, and which is a signal of alarm to the other inhabitants of the forest. During winter it resides in a burrow with several openings, made at the roots of a tree; and is even seen on the surface of the snow. At this season, when the snow disappears, many small collections of hazel-nut shells, from which the kernel has been extracted by a minute hole gnawed in the side, are to be seen on the ground near its holes." Dr. RICHARDSON further informs us that on the banks of the Saskatchawan, the mouths of the burrows of this species are not protected with heaps of vegetable substances, as described by Mr. SAY, and we have no doubt the animal adapts its nest (as many of our birds do) to the locality and circumstances that surround it. These animals bite severely when captured, and probably resemble Tamias Lysteri in their general habits and mode of living. GEOGRAPHICAL DISTRIBUTION. This species was originally discovered by SAY, who procured it on the Rocky Mountains, near the sources of the Arkansas and Platte rivers. We obtained it on the Upper Missouri, and Mr. DRUMMOND brought specimens from the sources of the Pearl river. It is found as far north as Lake Winnipeg, in lat. 50 degrees. GENERAL REMARKS. When we published Tamias minimus, we had some misgivings lest it might prove the young of the present species. The discoverer however assured us that the two species did not exist within many hundred miles of each other, and that the specimens he sent us were those of full grown animals; we consequently ventured on their publication. Having, however, since procured young specimens of T. quadrivittatus, we are satisfied of the error we committed, and hasten to correct it. In the investigation of species existing in distant and little known portions of country, it always requires a length of time to settle them beyond the danger of error. The traveller who makes these investigations very hastily, and seizes on a specimen wherever there is a moment's pause in the journey, is often himself deceived, and the describer, having perhaps only a single specimen, is very apt to fall into some mistake. The investigation of described species in every branch of natural history, both in Europe and America, occupied much of the time of the naturalists of our generation, who corrected many of the errors of a former age; most fortunate are they who are permitted to live to correct their own.
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