OCR Text |
Show APPENDIX C.- MAMMALS. 813 thighs. The dorsal line is inconspicuous, except on the darker tips of the short mane. Circumference of horn at the base 17 inches. Length of horn along the convexity 86} " Distance between the tips of horns 18 " The bighorn, at one time erroneously supposed to be the same as the old- world argali, is common in the ranges and hills belonging to the Rocky Mountain system. COLLECTED BY LIEUTENANT ABERT. 1. PSEUDOSTOMA CASTANOPS, Baird. This beautiful species was collected by Lieutenant Abert along the prairie road to Bent's Fort. In general colour it is of a pale yellowish- brown, with an ample patch of light chestnut on the side of the head and face, deepest above. The dorsal line is not darker than the rest of the fur. In size it is intermediate between P. borealis and bursarius. The colour of the fur above is slightly grizzled, and much lighter than in P . bursariu* ; beneath, paler. . Throat, space between the forelegs and sides of arms, pale rusty. The chestnut marking, on the side of the head, is very strongly defined, occupying on each side a nearly circular space of about one and three- quarter inches in diameter, with the nearly obsolete ear as a centre. These chestnut spaces do not quite meet on the crown and occiput, but leave a rectilinear interval, coloured like the rest of the back, of about one- eighth of an inch in width. On the muzzle, however, from above the eyes, the colour of opposite sides is confluent. The hind feet and toes are thinly covered with whitish hairs, which on the fore feet appear more ferruginous. The claws are white, but sufficiently transparent to allow the coagulated blood in the phalanges to show through them. Length to base of tail ( approximate) 8 inches. Tail 2| " Hand ( along the palm) 1^ " Length of exposed . part of middle anterior claw. } " Hind feet ( along sole) from heel 1^ " Middle daw \\ " |