15 Oregon Flying Squirrel
PTEROMYS OREGONENSIS.--Bachman. [Glaucomys sabrinus] OREGON FLYING SQUIRREL. [Northern Flying Squirrel] PLATE XV.--MALE AND FEMALE. P. magnitudine inter P. volucellam et P. sabrinum medius, supra fuscus, subtus luteo-albus; auribus P. sabrini auriculis longioribus; vellere densiore, membrana volatica largiore, pedibus grandioribus.
CHARACTERS. Intermediate in size between P. volucella, and the Northern species, P. sabrinus; ears, longer than in the latter, and far more compact; lobe of the flying membrane joining the fore-feet, much longer in proportion, making that membrane broader. Foot larger; general colour above, brown; beneath, yellowish-white. SYNONYME. PTEROMYS OREGONENSIS; Oregon Flying Squirrel, Bach., Jour. Acad. of Nat. Sciences, Phil., vol. viii., pt. i., p. 101. DESCRIPTION. This species differs from P. sabrinus, in several very striking particulars; the arm which supports the flying membrane is 11 1/2 lines in length, whilst that of the latter is only 9. Thus the smaller of the two has the largest flying membrane. The fur of P. sabrinus is much the longest, and is white, whilst that of P. Oregonensis has a yellowish tinge. The hairs on the tail of the former are only slightly tinged with lead-colour at the roots, whilst in the latter that colour extends outwardly, (towards the tips,) for half their length. The different shape of the ear, it being longer and narrower in our present species than in P. sabrinus, is a sufficient distinctive character. P. Oregonensis differs from the common flying squirrel (P. volucella) so entirely, that it is hardly necessary to give a particular comparison. Besides being much larger than the latter, and not possessing the beautiful downy-white on the belly, it, may be distinguished from P. volucella by the hairs on that species being white to the roots, which is not the case with the Oregonensis. Whiskers, numerous, and very long. COLOUR. Fur, deep gray at the base, on the back tipped with yellowish-brown; tail, pale-brown above, dusky toward the extremity; beneath, brownish-white; whiskers, chiefly black, grayish at the tips. Hairs covering the flying membrane, mostly black, slightly tipped with pale-brown; feet, dusky; around the eyes, brackish; ears, with minute adpressed brown hairs externally, and brownish-white internally. DIMENSIONS. Inches. Lines. Length from point of nose to root of tail . . . . 6 8 Tail, to point of fur . . . . . . . . . . . 6 0 Height of ear posteriorly. . . . . . . . . . 0 7 Breadth between the outer edges of the flying membrane . . . . . . . . . . . . 8 0 Longest hind-toe, including nail . . . . . . . 0 5 1/4 Longest fore-toe, including nail . . . . . . . 0 5 1/2 From heel to point of nail . . . . . . . . . 1 6 1/2 From nose to ear. . . . . . . . . . . . . 1 6 HABITS. The habits of this handsome Flying Squirrel, we regret to say, are almost unknown to us; but from its general appearance, it is undoubtedly as active and volatile as our common little species; and much do we regret that we have never seen it launch itself into the air, and sail from the highest branch of one of the enormous pines of the valley of the Columbia river, to some other tall and magnificent tree. Indeed, much should we like to know the many works of the Creator that yet remain to be discovered, examined, figured, and described, in the vast mountain-valleys and forests beyond the highest peaks of the great Rocky Chain. We hope, however, to obtain a good deal of information through various sources ere the conclusion of this work, from the remote portions of our Continent that have not yet been well explored by naturalists, and we shall then perhaps be able to say something more in regard to the subject of this article, of which we can now only add, that Mr. TOWNSEND remarks, that it inhabits the pine woods of the Columbia, near the sea, and has the habits of P. volucella. GEOGRAPHICAL DISTRIBUTION. Dr. RICHARDSON (Fauna Boreali Americana, p. 195) speaks of a Flying Squirrel which was "discovered by Mr. DRUMMOND on the Rocky mountains, living in dense pine-forests, and seldom venturing from its retreats except in the night." This animal he considers a variety of P. sabrinus, (var. B. Alpinus.) The locality in which it was found, and parts of his description, however, on the whole incline us to suppose that the specimen procured by Mr. DRUMMOND was one of our present species, although of a very large size. Dr. RICHARDSON says, "I have received specimens of it from the head of Elk river, and also from the south branch of the Mackenzie." So that if this supposition be correct, we may conclude that it inhabits a very extensive tract of country, and is, perhaps, most common on, and to the west, of the Rocky Mountains; in which last locality Mr. TOWNSEND met with it in the woods on the shores of the Columbia river. GENERAL REMARKS. There are no accounts of this species of Flying Squirrel, or of the larger one, P. sabrinus, in LEWIS and CLARKE'S Journal. Those travellers not having, as we suppose, heard of either, although they traversed a considerable portion of the country in which both species have since been found. We hope, when presenting an account of the habits of P. sabrinus, to be able to identity the variety above-mentioned, (P. sabrinus, var. B. Alpinus of RICHARDSON,) and if necessary, correct any error in our account of the geographical distribution of the present species (P. Oregonensis.)