| OCR Text |
Show 680 LIEUT.-COL. J. BIDBULPH O N T H E [June 16, Both types of the North-American Sheep have a large dirty-white posterior disk, which is very conspicuous except in the old males in summer, when the whole of the body becomes nearly white ; they have also a dorsal stripe, which is more or less conspicuous. In O. nivicola there is no disk showing above the tail ', though the posteriors are white and the dorsal stripe is wanting. There are other characteristics in which O. nivicola differs from the southern race of the Bighorn, but which it sbares with the northern race. In all three the horn is smoother, less wrinkled, and more goat-like in character than in other known species of true Wild Sheep ; but both O. nivicola and the northern race of the Bighorn have the horns less massive, and in both the points turn out abruptly, so that the tips are sharp and seldom broken, and point outwards ; while the southern race of Bighorn has the horns massive at the base, the tips blunt, generally broken, and pointing forwards. The ears in O. nivicola are very small and rounded, giving the idea that they have been cut, and are thickly furred to the edges. In the northern race of Bighorn the ears are also small and thickly furred, but have blunt points instead of being rounded. In the southern race of Bighorn the ears are broad, pointed, and deerlike, moderately coated with hair, and are, if anything, rather larger than in any of the known species of Asiatic Argali, measuring in the dried skin fully an inch longer than those of the northern race. Another point of distinction between the two races of Bighorn is in the size of the skull, the soutbern race having a skull averaging from an inch to an inch and a half longer, and from half an inch to one inch broader than the northern race. There are also considerable apparent differences in colour between the two races of Bighorn ; but I have not been able to examine a sufficient number of specimens to be sure how far these differences are constant. I have failed to find any specimens of the southern race with the dark winter coat like the specimen from Liard's River, nor can I find any mention of their ever assuming it. There appear to be also slight differences in the distribution of the colour on the legs. The northern race also has the hair between the ears at the back of the horns growing into a long curly tuft, which also happens in O. nivicola, but not in the southern race of Bighorn. The subjoined table contains some comparative measurements of specimens of the heads of the two races of the Bighorn. 1 This is clearly shown in Eschscholtz's figure of 0. nivicola (Zool. Atlas). |
