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Show 526 ON ASIATIC S H E E P . [June 15, z. Skull and horns in East-Indian Museum, presented by Mr. Hodgson. The orbital surface slightly convex at base, but becomes gradually flat; frontal surface slightly convex ; the nuchal surface convex. The fronto-nuchal and nuchal edges strongly marked ; the fronto-orbital edge rounded. Terminal axis directed upwards, outwards, and forwards. Conclusion.-M. Alphonse Milne-Edwards, in his ' Recherches pour servir a 1'Histoire Naturelle,' has indicated the probability of the Himalayas having been the birthplace of the Caprine Antelopes ; the same conclusion has suggested itself to our minds with reference to the Argali in studying their present distribution and differentiation. Taking the outlying forms of the group as regards geographical distribution, we find that we are led, either through intermediate or allied forms, to the great mountain-chain which forms the watershed between the Indian region and Central Asia. Ovis poli oi the Pamir, separated from Ovis hodgsoni of Thibet by the impassable glacier system of the Karakorum, which stretches over three degrees of longitude, from Hunza Nagar on the west to the Karakorum Pass on the east, is connected with that species by species of intermediate characteristics, which are distributed over intermediate ranges. The succession would be as follows:-Ovis poli, Pamir; Ovis karelini, Thian Shan as far eastward as Tengri Khan ; Oris ammon, the Altai from Tengri Khan as far as the Sea of Baikal on the east, and then southward over the great ranges at the sources of the Hoang-ho and Yang-se-kiang, its exact range in this latter direction being as yet very imperfectly known ; Ovis hodgsoni, Nepaul and Little Thibet. With reference to the three imperfectly known species, Oris brookei, Ovis heinsi, and Ovis nigrimontana, nothing at present can be conjectured. Ovis nivicola oi the Stanovoi Mountains and Ovis montana of North America, the two most isolated forms as to distribution, possess characters in common in which they differ markedly from all the other species ; and this fact, the facts of peculiarity of form and isolation of distribution being found side by side, appears to strengthen the probability of the hypothesis that these two species are the offshoots of the group whose early home and birthplace was in the Himalayas. The probability of this hypothesis is also strengthened by its applicability to the differentiation and distribution of the smaller forms of Sheep. Ovis musimon oi Corsica and Sardinia, and Ovis ophion of Cyprus, are undoubtedly very closely allied to Ovis gmelini ( = Ovis orientalis) of Asia Minor, and appear to us to be nothing but insular derivatives of that species. Ovis gmelini, on its part, so closely resembles Ovis vignei of Ladak that the horns of the two species cannot be distinguished apart. The exact distribution of this form is not perfectly known; but we possess a very fine specimen from Ararat, and Mr. Blanford's collection contained a male specimen from the Elburz Mountains, south of the Caspian Sea. Lastly, the sharply triangular-horned Sheep, of which Oris cycloceros is the type, are distributed from the mountains of Southern Persia and Beloochistan, through the Sulimani and Salt ranges, as far north as Thibet; and we possess specimens from these different ranges. |