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Show 418 MR. R. LYDEKKER ON THE [Apr. 6, conclusion that all the living forms have been differentiated from one another at a very recent epoch indeed, and probably in the Old World. On the whole, then, I am inclined to regard the various members of the group, with the exception of the Tibetan Blue Bear, as subspecies rather than species'. It is true that in some of the North American Bears the front claws are longer and straighter than in their Old World relatives, but this character does not serve to separate all the American forms as a species apart from all the latter. Neither, if I unite the Old World Bears, can I admit the right of all the American forms to stand as distinct species. I take this opportunity of mentioning that I am inclined to regard many mammals having representative forms in the two hemispheres as subspecies. This, I think, is the case with the Foxes, the Wolves, and the Weasels ; while the Asiatic Wapitis (Cervus eustephanus and the allied C. luehdorfi) are probably only races of the American C. canadensis. And I also think that the host of species recently made in North America out of the form which used to be known as Tamias asiatlcus will come under the same category. I am fully aware that in this view I shall be running atilt at all the modern school of American zoologists ; but I have, at least to some extent, on m y side men like Messrs. Blanford and Mivart, to whose opinions I attach the very highest value. And I also side with Huxley that it is a far less important error to overlook differences than not to see resemblances. In the following list 1 have endeavoured to arrange the Bears of the Ursus arctus group according to m y ideas of wdiat their classification should be. I have not attempted to give the whole synonymy, as in several cases I am at loss where to place synonyms. I. UBSUS ARCTUS.-Brown Bear. Ursus arctos, Linn. Syst. Nat. ed. 12, vol. i. p. 69 (1766). Ursus arctus, Blanford, Fauna Brit. Ind., M a m m . p. 194 (1888). Under this name I include all the brown, greyish, and grizzled existing Bears. In all these the cheek-teeth are large, the inner tubercle of tbe upper carnassial is large, the last lower molar has a large talon, and there is a considerable interval between the fourth lower premolar and the canine, in wdiich are situated the three anterior premolars in young individuals. The first lower premolar is very small, and the fourth large and generally furnished with two small tubercles on the inner side, one in advance of and the other behind the main cusp. The lower carnassial is also a large and complex tooth, generally with accessory cusps on the inner border of its talon. With regard to the two inner tubercles on the fourth lower premolar, a few words are necessary. As is well known to palseont- 1 If they are regarded as species, Ursus ought to be split up into several genera. |