American Big Game in Its Haunts: The Book of the Boone and Crockett Club. Various

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      Like American deer it has the lower ends of the lateral metacarpals remaining, and the antlers are without a brow-tine, but like Cervus it has an incomplete vomer, and unlike deer in general, the antlers are set laterally on the frontal bone, instead of more or less vertically, and the nasal bones are excessively short. The animal of northern Europe and Asia is usually considered to be distinct from the American, and lately the Alaskan moose has been christened Alces gigas, marked by greater size, relatively more massive skull, and huge antlers. Of the antecedents of Alces, as in the case of the reindeer, we are ignorant. The earlier Pleistocene of Europe has yielded nearly related fossils,[2] and a peculiar and probably rather later form comes from New Jersey and Kentucky. This last in some respects suggests a resemblance to the wapiti, but it is unlikely that the similarity is more than superficial, and as moose not distinguishable from the existing species are found in the same formation, it is improbable that Cervalces bore to AIces anything more than a collateral relationship.

      [Footnote 2: The huge fossil known as "Irish elk" is really a fallow deer and in no way nearly related to the moose.]

      Even to an uncritical eye, the differences between ungulates and carnivores of to-day are many and obvious, but as we trace them back into the past we follow on converging lines, and in our search for the prototypes of the carnivora we are led to the Creodonta, contemporary with Condylarthra, which we have seen giving origin to hoofed beasts, but outlasting them into the succeeding age. These two groups of generalized mammals approached each other so nearly in structure, that it is even doubtful to which of them certain outlying fossils should be referred, and the assumption is quite justified that they had a common ancestor in the preceding period, of which no record is yet known.

      The most evident points in which Carnivora differ from Ungulata are their possession of at least four and frequently five digits, which always bear claws and never hoofs; all but the sea otter have six small incisor teeth in each jaw; the canines are large; the molars never show flattened, curved crests after the ruminant pattern, but are more or less tubercular, and one tooth in the hinder part of each jaw becomes blade-like, for shearing off lumps of flesh. This tooth is called the sectorial, or carnassial.

      Existing carnivores are conveniently divided into three sections: Arctoidea—bears, raccoons, otters, skunks, weasels, etc.; Canoidea—dogs, wolves and foxes; Aeluroidea—cats, civets, ichneumons and hyaenas.

      It is highly probable that these three chief types have descended in as many distinct lines from the Creodonta, and that they were differentiated as early as the middle Eocene, but their exact degree of affinity is uncertain; bears and dogs are certainly closer together than either of them are to cats, and it is questionable if otters and weasels—the Mustelidae, as they are termed—and raccoons are really near of kin to bears.

      Seals are often regarded as belonging to this order, but their relation to the rest of the carnivores is very doubtful. Many of their characters are suggestive of Arctoidea, but it is an open question if their ancestors were bear or otter-like animals which took to an aquatic life, or whether they may not have had a long and independent descent. At all events, doubt is cast upon the proposition that they are descended from anything nearly like present land forms by the fact that seals of already high development are known as early as the later Miocene.

      The difficulty so constantly met with in attempting to state concisely the details of classification, is well shown in this order, for its subdivisions rest less upon a few well defined characters than upon complex associations of a number of lesser and more obscure ones, a recapitulation of which would be tedious beyond the endurance of all but practiced anatomists. For the present purposes it must be enough to say that bears and dogs have forty-two teeth in the complete set, of which four on each side above and below are premolars, and two above, with three below, are molars, but these teeth in bears have flatter crowns and more rounded tubercles than those of dogs, and the sectorial teeth are much less blade-like, this style of tooth being better adapted to their omnivorous food habits. Bears, furthermore, have five digits on each foot and are plantigrade, while dogs have but four toes behind and are digitigrade. These differences are less marked in some of the smaller arctoids, which may have as few as thirty-two teeth, and come very near to dogs in the extent of the digital surface which rests upon the ground in walking.

      In distinction from these, Aeluroidea never have more than two true molars below, and the cusps of their teeth are much more sharply edged, reaching in the sectorials the extreme of scissor-like specialization. In all of them the claws are more or less retractile, and they walk on the ends of their fingers and toes.

      Cats are distinguished from the remainder of this section by the shortness of the skull, and reduction of the teeth to thirty, there being but one true molar on each side, that of the upper jaw being so minute that it is probably getting ready to disappear.

      Civets, genets, and ichneumons are small as compared with most cats; they are fairly well distinguished by skull and tooth characters; their claws are never fully retractile, and many have scent glands, as in the civets. No member of this family is American.

      Hyaenas have the same dental formula as cats, but their teeth are enormously strong and massive, in relation to their function of crushing bone.

      No carnivore has teeth so admirably adapted to a diet of flesh as the cat, and, in fact, it may be doubted if among all mammals, it has a superior in structural fitness to its life habits in general.

      The Felidae are an exceedingly uniform group, although they do present minor differences; thus, some species have the orbits completely encircled by bone, while in most of them these are more or less widely open behind; in some the first upper premolar is absent, and some have a round pupil, while in others it is elliptical or vertical, but if there is a key to the apparently promiscuous distribution of these variations, it has not yet been found, and no satisfactory sub-division of the genus has been made, beyond setting aside the hunting-leopard or cheetah as Cynaelurus, upon peculiarities of skull and teeth.

      True cats of the genus Felis were in existence before the close of the Miocene, and yet earlier related forms are known. Throughout the greater part of the Tertiary the remarkable type known as sabre-toothed cats were numerous and widely spread, and in South America they even lasted so far into the Pleistocene that it is probably true that they existed side by side with man. Some of them were as large as any existing cat and had upper canines six inches or more in length. Cats have no near relations upon the American continent, nor do they appear to have ever had many except the sabre-tooths. Of present species some fifty are known, inhabiting all of the greater geographical areas except Australia. They are tropical and heat loving, but the short-tailed lynxes are northern, while both the tiger and leopard in Asia, and puma in America, range into sub-arctic temperatures, and it is a curious anomaly that while Siberian tigers have gained the protection of a long, warm coat of hair, pumas from British America differ very little in this respect from those of warm regions.

      No other cat has so extensive a range as Felis concolor and its close allies, variously known as puma, cougar and mountain lion, which extends from the Atlantic to the Pacific, and from latitude fifty-five or sixty north, to the extreme southern end of the continent. As far as is known, it is a recent development, for no very similar remains appear previous to post-tertiary deposits.

      Bears of the genus Ursus are of no great antiquity in a geological sense, for we have no knowledge of them earlier than the Pliocene of Europe, and even later in America, but fossils becoming gradually less bear-like and approximating toward the early type from which dogs also probably sprung, go back to the early Tertiary creodonts.

      Cats, as we have seen, are chiefly tropical, while bears, with two exceptions, are northern, one species inhabiting the Chilian Andes, while the brown СКАЧАТЬ