The Cambridge Natural History Part 34

_Amphicyon_, forming the type of another sub-family, Amphicyoninae, though usually placed among the Dogs, presents us with {424} many Bear-like features in its organisation. The feet, for instance, were plantigrade and five-toed. The ulna and the radius are specially compared with the same bones in the Bear tribe. The skull on the other hand is as distinctly Dog-like in form. The molars are large, broad, and crushing, and Bear-like.

The largest known species, _A. giganteus_, is of about the size of the Brown Bear. _Amphicyon_ is a Miocene genus. Eocene and allied to it is _Pseudamphicyon_. This genus has, like _Amphicyon_, the complete dent.i.tion of forty-four teeth. In the Amphicyoninae generally the feet are five-toed, the humerus has an entepicondylar foramen and the femur a third trochanter.

The upper molars are large.

The closely allied and American genus _Daphaenus_ has also plantigrade feet, and has in its structure many reminiscences of the Creodonts. So, too, has the Eocene _Uintacyon_.

_Cynodesmus_ is closely allied to _Cynodictis_. It has ancient features combined with quite modern ones. The skull is described as being Creodont-like, but the dent.i.tion is that of the microdont modern Dogs. In accordance with its age the cerebral convolutions of this Dog are much simpler than in existing Dogs, and the hemispheres do not cover the cerebellum so much.

THE BEAR-LIKE CARNIVORA OR ARCTOIDEA.--That division of the Carnivora which is typically represented by the Bears embraces three recent families, which are united by a number of characters. These Carnivora are always plantigrade or nearly so. They have nearly always five toes. The claws are not retractile, or at most semi-retractile as in the Panda. In the skull the tympanic bulla is often depressed, and is not so globular and obvious as in the Cats. Its cavity is not divided by a septum. The paroccipital processes are not applied to it. The carna.s.sial tooth is less emphasised in this group than in the Cats.

These characters, however, have to be used with caution, as they are hardly universally applicable. A fairly typical Arctoid bulla is seen in such a form as _Cercoleptes_. The bulla itself is a little more swollen than in _Ursus_, but it is flattened off in the same way towards the bony meatus.

The paroccipital processes, slightly developed, are at a distance of -inch from the posterior margin of the bulla. In the Racc.o.o.n the bullae are much more swollen, and the paroccipital processes are closer to them. In the Marbled Polecat, _Putorius sarmaticus_, the bullae are fairly {425} swollen, and there is but little flattening towards the meatus: the paroccipital processes, though slight, are in contact with the bullae basally, though their free tips are turned away from them. Finally, in _Ictonyx_ the bullae are much swollen; there is but little flattening towards the meatus, and the paroccipital processes, themselves much swollen, are pressed closely against the bullae. The Mustelidae, therefore, in this as in other characters, approach the Aeluroids.

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FIG. 212.--Section of the left auditory bulla and surrounding bones of a Bear (_Ursus ferox_). _am_, External auditory meatus; _BO_, basioccipital; _Car_, carotid ca.n.a.l; _e_, Eustachian ca.n.a.l; _g_, glenoid ca.n.a.l; _Sq_, squamosal; _T_, tympanic; _t_, tympanic ring. (From Flower, _Proc. Zool.

Soc._ 1869.)

There is no caec.u.m, a feature which marks off the Arctoidea from all Carnivora except the Viverrids _Nandinia_ and _Arctictis_ (occasionally).

The brain is characterised by the possession of what Dr. Mivart has described as the "ursine lozenge," a tract about the middle of the hemispheres, defined posteriorly by the crucial sulcus, and formed by the emergence on to the surface of the brain of the hippocampal gyrus.

The Arctoidea are very widely distributed. But there are some curious exceptions. Thus there are no representatives of the group (as might be expected) in the Australian region; they are completely absent from Madagascar; while the true Bears (family Ursidae) are totally absent from Ethiopian Africa, and are only represented by a single species, _Ursus ornatus_, in the Neotropical region.

It is noteworthy that the Arctoidea never show spots or {426} cross stripes (save rings on the tail), which are so common a feature of the coloration of the Cat-like forms.

In bracketing together the three families which are described in the following pages, emphasis is laid upon a number of undoubtedly common features. Palaeontology seems, however, to suggest that the Mustelidae come nearer to the Viverridae. That the Bears and Dogs are connected by extinct annectent genera does not interfere with their present distinctness.

The systematic arrangement of these Carnivora is not easy. It may be useful, however, to give a method of arrangement for the convenient placing of the genera.

The most primitive group is perhaps that of the true Bears, family Ursidae; for in them the molars are two above and three below, and have thus not become diminished in number as in some of the other members of the order.

Moreover, the Bears have lobate kidneys, which character, often occurring in the young of animals which when adult have smooth kidneys, may be looked upon as a primitive character. The feet furthermore are completely plantigrade. This family will contain only three genera, _Ursus_, _Melursus_, and _Aeluropus_.

Next comes the family Procyonidae, in several members of which one molar is lost below, though in others the more archaic formula is retained. The kidneys are simple. This family contains the American genera _Procyon_, _Nasua_, _Ba.s.sariscus_, _Ba.s.saricyon_, _Cercoleptes_, and the Old-World form _Aelurus_.

The third family, Mustelidae, has the molar formula reduced to 1/2 or 1/1.

The kidneys are simple except in the Otters. To this family are a.s.signed the following genera:--_Arctonyx_, _Conepatus_, _Meles_, _Mephitis_, _Taxidea_, _Mydaus_, _Mellivora_, _Helictis_, _Ictonyx_, _Mustela_, _Galictis_, _Grisonia_, _Putorius_, _Gulo_, and the aquatic _Lutra_, _Enhydris_, and _Aonyx_.

FAM. 6. PROCYONIDAE.--This family is mainly American in range, the genus _Aelurus_ alone being a native of the Old World. But Zittel would include with the genera of this family the Viverrine and Oriental genus _Arctictis_, a proceeding which is perhaps hardly admissible, though the occasional absence of a caec.u.m in that animal is so far in favour of such an alliance. The largely vegetable nature of its food and its arboreal habits cause a certain amount of likeness to some of the members of the present group of Carnivores. The Procyonidae have two {427} molars in either half of each jaw. The carna.s.sial teeth are not typically developed, and the molars are broad and tuberculate. The tail is long, often prehensile, and often ringed in the disposition of its colour pattern. The alisphenoid ca.n.a.l is absent save in the aberrant _Aelurus_. Both condyloid and postglenoid foramina are present. The members of this family are plantigrade.

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FIG. 213.--Racc.o.o.n. _Procyon lotor._ 1/5.

The genus _Procyon_ includes at least two species of Racc.o.o.n, the northern form, _P. lotor_, and the South American, _P. cancrivorus_. To these may possibly be added a third, _P. nigripes_. This genus is characterised by the length and the mobility of the fingers, and indeed it uses its hands greatly. It has no median groove upon the muzzle, which is found in many other Arctoids; the ears are moderately large; the tail is not long, being about one-third of the entire length of the animal, including the tail. The soles of the feet are naked. Its limbs are very long (for an Arctoid), and this gives to the animal a bunched-up appearance when walking. There are four premolars and two molars on each side of each jaw. There are fourteen pairs of ribs, of which ten pairs reach the sternum. The latter is composed of nine pieces.

The first-named species has received its name from the fact--of which there is abundant proof--that it dips its food into water. As a matter of fact, the animal frequents the margins of streams, and hunts in the shallow water beneath stones for {428} crayfish, and it also captures fish. Not only is this animal partially aquatic, but it can climb well--"they make their homes in trees, but carry on their business elsewhere." The animal can be readily tamed, but is a tiresome pet on account of its insatiable curiosity and its skill in the use of its hands, which enables it to unlatch doors and generally to pry about everywhere. The Racc.o.o.ns are mostly nocturnal creatures.

The genus _Ba.s.saricyon_[296] includes two species, both American, _B.

alleni_ being from Ecuador, and _B. gabbii_ from Costa Rica. They have so much the aspect of a Kinkajou that a specimen, which arrived at the Zoological Gardens, was presented and entered as one of those animals.

Nevertheless there are many differences between the two genera. The tail of _Ba.s.saricyon_ is not prehensile, and the animal, as will be seen from Fig.

214, has a sharper snout; the brain is more like that of _Ba.s.sariscus_. The likeness to _Cercoleptes_ can hardly perhaps be regarded as an example of "mimicry" since the forms are so nearly related, and the advantage of such an imitation remains to be proved. The muzzle of _Ba.s.saricyon_ is grooved; the ears are fairly large; the soles of the feet are naked; there is but a single pair of teats. There are two molars and four premolars to each half jaw.

[Ill.u.s.tration]

FIG. 214.--Ba.s.saricyon. _Ba.s.saricyon alleni._ 1/5.

The dorsal vertebrae are thirteen in number; nine of the ribs reach the sternum. The slenderness and convexity of the lower margin of the lower jaw, as well as the feeble angular process, distinguish this genus from its undoubtedly near ally _Cercoleptes_. The dental formula also is different.

_Ba.s.sariscus_ has a ringed tail like a Racc.o.o.n, and is also American in range; it furthermore agrees with the Racc.o.o.n in {429} being nocturnal and mainly arboreal in habit. There are apparently three species, of which _B.

astutus_ is the best known, having been on several occasions exhibited at the Zoological Society's Gardens, the last examples so lately as 1900. The animal was for a long time believed to be allied to the Oriental Paradoxures, and its occurrence in America was therefore puzzling. The real affinities of the creature were, however, definitely set at rest by Sir W.

Flower, and later accounts of its anatomy have confirmed this opinion.[297]

The vertebrae are more numerous than in _Procyon_, and the teeth are slightly different; otherwise it presents many likenesses to its nearest ally. The ears are long; the nose is grooved; and the palms and soles are naked.

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FIG. 215.--Cunning Ba.s.sarisc. _Ba.s.sariscus astutus._ 1/5. (From _Nature_.)

The Kinkajou, _Cercoleptes_, is likewise an American Arctoid. It ranges from Central Mexico down to the Rio Negro in Brazil. It was at one time confounded, and, considering its external appearance, not unnaturally, with the Lemurs. Sir R. Owen dispelled this view by a careful dissection of the creature. Nevertheless, there are certain anatomical features in which it differs {430} from Carnivora and resembles Lemuroids.[298] It has been pointed out that the form of the lower jaw "much resembles that of the Lemuroid _Microrhynchus_." There is, however, no doubt that it is rightly placed in the present group. The tail is very prehensile, and the animal is therefore, as might be supposed from this circ.u.mstance, purely arboreal. It has some twenty-eight vertebrae. This genus has a median groove upon the nose. The claws are long and sharply pointed, and the palms and soles of the feet are naked. The premolars are three, the molars two. There are fourteen dorsal vertebrae, of which nine are united to the nine-jointed sternum by ribs. There is but one species, _C. caudivolvulus_, of a uniform yellowish-brown colour.

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FIG. 216.--Kinkajou. _Cercoleptes caudivolvulus._ 1/6.

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FIG. 217.--Coati. _Nasua rufa._ 1/6.

_Nasua_, the Coati, ranges from Texas to Paraguay, and has two species. In Guatemala it reaches a height of 9000 feet on the mountains. The nose is produced into a short and very {431} mobile proboscis, hence its name. The native Mexican name for the creature is "Quanhpecotl."

The Coati is largely arboreal, and hunts iguanas in large bands, some of them being on the trees and some on the ground beneath. It also grubs up worms and larvae, for which purpose its long snout is suited. The molars of the genus resemble those of _Procyon_.

There is not a median groove upon the nose. The palms and soles are naked.

Six teats occur. There are thirteen dorsal vertebrae. _Nasua nasica_[299]

and _N. rufa_ are the best known and perhaps the only species. The colour of the fur varies a good deal, and has led to the use of other names for supposed species.

_Aelurus_, the Panda, is a largish animal found in the south-eastern Himalayas up to a height of 12,000 feet. It has a glossy fur of a reddish colour, and a "white somewhat cat-like face." The molar formula which distinguishes it from the New-World Arctoids belonging to the Procyonidae, as well as from its possible ally _Aeluropus_, is Pm 3/4 M 2/2. The anatomy of the animal has been described by Sir W. Flower.[300] Dr. Mivart has pointed out that the muzzle though short is upturned in a way distinctly recalling that of _Nasua_. The animal inhabits forests, and feeds almost entirely upon vegetable food. It eats eggs, however, and insects. Though living to a great extent upon the ground, it is also arboreal, and has sharp semi-retractile claws. It is said to be dull of sight, hearing, and smell, and yet with these disadvantages is also unprovided with cunning or ferocity. Its habits have been compared with those of a Kinkajou.

FOSSIL PROCYONIDAE.--In addition to several of the existing genera, the remains are known of various extinct forms of Procyonidae. _Leptarctus_, with one species, _L. primaevus_, is of Pliocene age, but is known only by one ramus of the lower jaw. It appears to "offer a number of transitional characters between the more typical Procyonidae and the aberrant _Cercoleptes_."[301]

FAM. 7. MUSTELIDAE.--Contrary to what has been stated with regard to the habits of the Procyonidae, the Mustelidae are for the most part "bloodthirsty robbers," and are spread over the {432} whole surface of the world, with the exception of Australia and Madagascar. The molar teeth are generally reduced to one in the upper jaw, and sometimes to one in the lower jaw, which thus gives "a sort of _prima facie_ resemblance to the feline dent.i.tion." There is no alisphenoid ca.n.a.l; postglenoid and condyloid foramina are found.

SUB-FAM. 1. MELINAE.--Of this sub-family there are representatives both in the Old and New Worlds.

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FIG. 218.--Badger. _Meles taxus._ 1/6.

_Meles_, the Badger, is exclusively Palaearctic in range.[302] Dr. Mivart says that _Meles_ has a relatively longer dorsal region than any other Carnivore, and that it is most nearly approached by its allies _Ictonyx_ and _Conepatus_. The molar formula is, as in _Arctonyx_, _Mydaus_, and _Helictis_, Pm 4/4 M 1/2. The molars differ from those of any other Carnivore in the much greater size of the first molars than of the last premolars. The nose is not grooved; the soles of the feet are naked. The claws of the fore-feet are much longer than those of the hind-feet.

The genus _Arctonyx_ is a "pig-like badger" from Hindostan, a.s.sam, and North China. The epithet "pig-like" is derived from the long and mobile snout, which is truncated and has terminal nostrils. It is remarkable for having a part of the palate formed by the pterygoids, as in Whales and certain Edentata (e.g. _Myrmecophaga_). There are sixteen dorsal vertebrae.