CARNIVORES or CARNIVORA, members of the order of flesh-eating mammals which includes the most powerful and ferocious beasts of prey, as the lion, tiger, leopard and jaguar, numerous fur-bearers, as the seal, fox and sable, the domesticated cat and dog and other well-known animals. In general, their teeth, especially the four long, piercing canine teeth, are adapted for tearing flesh, and the toes of many species are provided with strong sharp claws for seizing prey. For the most part, the carnivores are very active, intelligent and courageous animals, with a keen sense of sight and smell. In size carnivores vary greatly, ranging from small weasels to huge bears, which may weigh a ton. There are about 30o species which, in their rela tionships form four well-marked groups : the catlike, the doglike, the bearlike and the seallike or marine carnivores. Among those comprising the catlike group are the true cats, the lion, leopard, puma, lynx, domestic cat, etc., and also the civets, genets, mon gooses, and hyaenas. In the doglike group are found the dogs, wolves, jackals and foxes. Besides the true bears, the bearlike group includes the raccoons, coatis, weasels, otters, martens, badgers, and the panda. In the seallike group are the true seals, the sea-lions and the walruses. The carnivores are well repre sented in all parts of the world except the Australian region, which contains only the dingo, a wild dog, doubtfully native. The polar bear and the polar fox range further north than all other land mammals, while sea-lions are found in both arctic and ant arctic waters. However, some important groups are restricted in their distribution. The numerous civets, for example, are confined to the Old World; the raccoons, except the panda, occur only in America, while in most of Africa none of the true bears are found. Though some carnivores are destructive to domestic animals, and even to human life, many are valuable fur-bearers, as the sable, otter, marten, mink, fox and fur-seal, and they also hold in check various animals, as rodents, which, if unrestricted in numbers, would become exceedingly injurious to agriculture. Besides, the dog and the cat, which have been household animals since ancient times, the cheeta or hunting leopard, the ferret and the mongoose are domesticated. (See articles on the various ani mals mentioned.) (X.) The term Carnivora, suggesting that all the animals so desig nated are flesh-eaters, is not entirely appropriate. Certain highly organized species of the cat, wolf and weasel kind live almost wholly upon the flesh of warm-blooded animals, for the capture of which their habits and structure are admirably adapted; but others, like most bears, are almost wholly vegetable feeders and quite unfitted for the chase. The great variation in diet and mode of life exhibited by the order is accompanied by a corresponding variation in the limbs and other external organs and by the teeth and skeleton. No single character absolutely distinctive of the group can be named; but by the combination of a number of structural features, it may be distinguished from other orders of mammals.
There are never fewer than four toes on each foot ; and the first is never opposable to the rest ; the digits are typically armed with compressed claws, never with nails or hoofs; there are typically two tufts of tactile vibrissae on each cheek; the tail is never absent ; the anus and genital organs open by separate apertures, and the mammae are never wholly pectoral. The cranial portion of the skull is always tolerably capacious as compared with the facial portion and the brain is well or moderately well convoluted. There are two sets of teeth, milk and permanent, differentiated into incisors, canines and cheek-teeth. The incisors are typically six in number above and below, the centrals never being larger than the laterals. The canines are almost always long and piercing in both jaws. The cheek-teeth are rooted, never of persistent growth, and the enamelled crown is raised into simple or blade-like cusps. The two halves of the uterus are separate and the placenta is deciduate and generally zonary.
Rhinarium.—The nostrils are typically surrounded by a con spicuous area of naked, glandular skin, the rhinarium, continued in front to the edge of the upper lip as a strip of grooved skin, the philtrum. It is subject, however, to considerable variation with habits.
Ear.—There is typically a well-developed erect external ear, or pinna, attached by a broad hollowed base of which the walls are strengthened by cartilaginous ridges. One of these, the supratragus, is sometimes valvular, helping to close the ear orifice. Another character of importance is the bursa, a pocket formed by a supple mentary flap low down on the posterior margin of the ear. Feet.—In the generalized, and probably primitive, type there are five digits tolerably evenly spaced and forming with their tips a strongly and fairly evenly curved series, the third and fourth being the longest, the second and fifth shorter and subequal, and the first the shortest. Each is supplied with an inferior digital pad behind the claw ; and they are united by a flap of integument, or web, which extends nearly to the digital pads. The sole is provided with a plantar pad composed of four united lobes. Behind the plantar pad there is on the f ore-foot a pair of large, lobate carpal pads ; and on the hind-foot there is a pair of elongated metatarsal pads, which extend nearly to the heel. This type of foot, called subplantigrade, passes by imperceptible gradations into feet contrasted as digitigrade and plantigrade. The typical plantigrade foot is broad and short, the plantar pad is considerably wider than long, the digits are nearly equal in length and their pads form a lightly curved row. The typical digitigrade foot is longer and narrower than the subplantigrade foot and has the first digit short and raised off the ground or absent ; the plantar is three-lobed and the area above it is hairy.
There are two types of claw in the digitigrade foot, the short blunt claw of the dogs and hyaenas and the sharp, retractile claw, found in some civets and most cats, which is modified for lacera tion of prey. The terminal bone of the digit is retracted by an elastic ligament and the sharp point of the curved claw is protected from wear by lobes of skin which ensheathe it. In the seals the feet are converted into paddles, but their structure suggests that they also are modifications of the subplantigrade foot.
Anal Glands.—The rectum is typically provided with a pair of glands opening, usually by a single aperture, just within the anal orifice. The secretion probably acts in normal cases as a lubricant or disinfectant ; but in some genera, especially of Mustelidae, like the skunks, the secretion is abundant and nauseous and its forcible discharge is an important means of defence. In the bears (Ursidae) the glands are developed to a negligible extent ; and they are quite absent in the seals.
External Genitalia.—The perinaeal area, lying between anus and generative orifice, varies greatly in extent, especially in the males. It may be small, the penis being short and close to the scrotum. But in most families the perinaeal area is large, the penis being long, with the prepuce remote from the scrotum.
On the palate there is a pair of orifices, the posterior palatine foramina, which are typically situated on the maxillo-palatine suture but may be in advance of it.
The bone containing the ear capsule, is covered by the auditory bulla, composed either wholly or partly of the tympanic bone, which always forms its anterior part. The posterior part is occa sionally cartilaginous, but it may be ossified from a separate centre, the entotympanic. In this type of bulla its cavity is always divided into two chambers by a bony partition, which passes from the line of junction of the two bones.
Behind the bulla there is an expansion of the occipital bone, the paroccipital process, and behind the auditory orifice another process, called the mastoid. Low down on the inner wall of the temporal fossa there is frequently a bony channel, the alisphenoid canal, through which passes a branch of the carotid artery. Its incidence is remarkable, and it has been much used in classification.
The Carnivora are usually divided into two sub-orders : the Pinnipedia, or seals, with paddle-like feet and the cheek-teeth all alike, and the Fissipedia, or typical forms with paw-like feet and dissimilar cheek-teeth. And the Fissipedia are further divided into two tribes : the Arctoidea, comprising the dogs, bears, raccoons, weasels and their allies, and the Aeluroidea, or Herpestoidea, corn prising the cats, hyaenas, civets, mongooses and others. But the feet and the cheek-teeth are too variable and plastic to be used as a basis for the primary division of the order into Pinnipedia and Fissipedia. The whole organization of the seals points to their affinity with and descent from the Arctoid group of carnivores. The old classification must, therefore, be abandoned and the seals referred to the Arctoidea.
The Carnivora, then, may be divided into two sub-orders, the Aeluroidea and the Arctoidea, which are mainly distinguished by cranial characters.
The single species of this genus, N. binotata, sometimes called the two-spotted palm civet, is a spotted, omnivorous, arboreal animal the size of a small cat, restricted to the forest region of west Africa. It is an extremely interesting primitive type, re sembling in many cranial and dental characters, especially in the structure of the bulla, the extinct Miacidae of the Eocene.
Viverridae.—The civets, genets and their allies composing this family differ from the Nandiniidae in having the auditory bulla divided by a partition, the wall of its posterior chamber completely ossified and its posterior surface applied to the paroccipital process, which projects downwards, and in the relatively small size of the mastoid process. Also the scent glands, when present, are either wholly or partly perinaeal, never entirely abdominal in position. The family exhibits great range in structural variation and is divisible into several sub-families.
The Paradoxurinae, the Oriental palm civets, closely resemble Nandinia in external form and habits, but in the male the prepuce is far in advance of the scrotum, the intervening area being usually occupied by a large but simple scent-pouch, and in the female the vulva is surrounded by the scent-gland. This group, ranging from India to the Philippines and Celebes, is represented by the genera Paradoxurus, Paguma and Macrogalidia. In a related form, Arctogalidia, the scent-gland is absent in the male, and in the binturong (Arctictis) the tail is prehensile and the teeth, as in Arctogalidia, are not so trenchant as in the typical palm civets.
In the three Oriental genera of Hemigalinae (Hemigalus, Diplo gale, Chrotogale) the teeth are sharper cusped than in the last, the feet are more digitigrade and the scent-pouch is reduced in size in both sexes.
The otter-civet (Cynogale), the type of the Cynogalinae, is a fish-eater adapted for aquatic life. The vibrissae are numerous and rigid, the rhinarium is on the summit of the muzzle, which is very wide, and the tail is short. The scent-gland is reduced and the teeth are modified for holding fish and crushing the shells of crabs and mussels. The genus ranges from the Malay States to Borneo.
The Viverrinae, represented in tropical Asia by the civets (Viverra, Viverricula) and in Africa by the typical civet cat (Civettictis) and the genets (Genetta, Poland), differ from the Paradoxurinae in being digitigrade, generally with retractile claws, in having more elaborate scent-glands and more trenchant teeth.
In the Galidictinae or Madagascar mongooses (Galidia, Gall dictis, Hemigalidia), the scent-gland is restricted to the female, the feet are narrow with non-retractile claws, the jaws are short, the teeth sectorial and the bulla has a bony tubular meatus not found in the other sub-families.
In the preceding groups the scent-gland is present in one or both sexes. In the following three it is absent : Fossa, the sole representative of the Fossinae, is a civet-like animal inhabiting Madagascar; digitigrade but with non-retractile claws; Eupleres, the only known form of the Euplerinae, also comes from Mada gascar, is remarkable for the degenerate character of the teeth and feeble jaws, and the feet are subplantigrade and fossorial; and the linsangs (Prionodon and Pardictis), representing the Prionodontinae, elegant genet-like animals found in south-eastern Asia, with digitigrade feet and retractile claws, are the only mem bers of the Viverridae in which the penis is small and close to the scrotum.
Herpestidae.—The mongooses differ from the Viverridae in possessing a glandular circumanal sac into which the anus and anal glands open by separate orifices, and in the absence of the bursa on the ear. They have no perinaeal glands, the penis is short and close to the scrotum and there is a tubular auditory meatus in the skull. The feet are digitigrade or subplantigrade with fossorial non-retractile claws and the toes may be reduced to four on each foot. The teeth also vary, sometimes being bluntly, sometimes sharply cusped and trenchant. The family contains a large number of genera and species found mostly in India and Africa. The best known are Herpestes, the typical mongoose; Mungos, the banded mongoose; Iclineumia; Suricata, and others.
Cryptoproctidae.—The fossa (Cryptoprocta), found in Mada gascar, externally somewhat resembles the palm civets of Asia, but differs in the absence of perinaeal scent-glands, the posses sion of a capacious circumanal sac and of a large bone in the penis, this organ being highly complex in structure. The jaws of the skull are short and the teeth are sectorial, closely resembling those of the Felidae.
Hyaenidae.—The hyaenas (Hyaena, Crocuta) differ from all the other families of Aeluroidea in the large size of the tym panic bone which composes nearly the whole of the bulla, the partition of the cavity lying far back. The feet are digitigrade, like those of a dog, but there is no pollex. The anal glands open into a capacious subcaudal pouch. There are no perinaeal glands and the prepuce is far in advance of the scrotum. The skull is massive and the teeth which are sectorial in type are very power ful. The genus Hyaena is represented by the striped hyaena of south-western Asia and northern Africa and by the brown hyaena of south-western Africa. Crocuta, the spotted hyaena, which differs in the structure of the teeth and genital organs, is re stricted to Africa. Hyaenas are mostly scavengers, feeding upon the carcases of big game.
Protelidae.—The aard-wolf (Proteles) of tropical and southern Africa, resembles a small striped hyaena in external characters, except for the presence of a pollex on the forefoot. It differs, however, from the hyaenas in the normal structure of the bulla and from all the land carnivores in its remarkable dentition, the cheek-teeth being widely spaced, all alike and peg-like, with the jaws correspondingly weak. It eats carrion and white ants. Felidae.—The cats are distinguished by the position of the posterior palatine foramina on the maxillo-palatine suture and the invariable absence of the interramal tuft of vibrissae. As in the linsangs (Viverridae), the penis is small and close to the scrotum, the vulva close to the anus, and there are no perinaeal glands or glandular pouch above or around the anus ; but although the feet have retractile claws, they are more digitigrade than in the linsangs, the pollex being more elevated, the hallux absent and the plantar pad three-lobed. In the skull the jaws are short and the teeth highly sectorial, the important cheek-teeth being the two blade-like carnassials. There are three sub-families:— the Pantherinae, containing the lion (Panthera leo), the tiger (P. tigris), the leopard (P. pardus), the jaguar (P. onca), and the snow-leopard (P. uncia), which have the larynx loosely attached to the skull by the largely ligamentous suspensorium of the hyoid; the Felinae, containing a large number of genera, Neo f elis, the clouded leopard (N. nebulosa) ; Leopardus, the ocelot (L. par dalis) ; Puma, the puma (P. concolor) ; Felis, the wild cat (F. sylvestris) ; Lynx, the lynx (L. lynx) ; and many others which have the suspensorium of the hyoid normally ossified ; and the Acinonychinae, containing the cheetah (Acinonyx jubatus), which is distinguished by the absence of integumentary sheaths to the claws, the hyoid being as in the Felinae.
Arctoidea.—In the sub-order Arctoidea, containing the rest of the existing carnivores, the ethmo-turbinals are excluded from the anterior orifice of the nasal chambers by the enlarged maxillo turbinals. The wall of the auditory bulla is composed solely of the tympanic bone and its cavity is typically undivided. Cowper's glands are present in the male.
The families fall into two series, the Fissipede arctoids, con taining the dogs, bears, raccoons, weasels and their allies, and the Pinnipede arctoids, containing the sea-lions, walruses and seals.
In the Fissipede arctoids the feet and the teeth are structurally and functionally similar to those of the Aeluroidea. Only in the sea otter are the hind-feet paddle-like.
Canidae.—The dogs, wolves and foxes differ from the rest of the Arctoids in possessing a caecum and a duodeno-jejunal flexure in the intestine, as in the Aeluroids. Also they are completely digitigrade and typically the formula of the cheek-teeth is PI, M 3, with the carnassials large and secant. The teeth, however, vary. The genus Canis, containing the dogs, wolves and jackals, many related genera from South America, and the foxes (Vulpes) have the teeth as recorded above; but the Asiatic dholes (Cuon) and the South American bush dog (Speothos) have lost the third lower molar. The most aberrant dentition, however, is found in the fox-like African genus Otocyon in which there are not only f our lower and three, occasionally four, upper molars, but the carnassial teeth are not differentiated from the rest either in size or function. Another somewhat aberrant type is the African hunt ing-dog (Lycaon) in which the ears are large and rounded and the pollex is absent.
Ailuropodidae.—The giant panda (Ailuropoda melanoleuca), inhabiting Tibet and southern China, resembles a black and white bear in appearance, but differs from all the Ursidae in the pres ence of a digit-like bone rising on the inner side of the fore-foot, and associated with a corresponding expansion of the plantar pad, and in the absence of the alisphenoid canal and the structure of the teeth. The premolars are not reduced and the molars are even larger and supplied with numerous supplementary cusps.
Ailuridae.—The common panda (Ailurus fulgens), which occurs in southern China and north-eastern India, is a small, long-tailed, arboreal species, with subplantigrade, sharp-clawed, hairy feet with greatly reduced pads, the supplementary bone on the f ore f oot being quite small. It also differs from the giant panda in the loss of the third lower molar, in the cheek teeth forming graduated series and being simpler in pattern and in the presence of the alisphenoid canal. The anus is encircled by a glandular pouch and the penis is small and close to the scrotum as in some Aeluroids.
Procyonidae.—This family, confined to America, differs from the Ailuridae in having the penis long, the prepuce remote from the scrotum and the anal sac and alisphenoid canal absent, in the normally developed pads on the feet and the differentiation of the upper carnassial from the third premolar. There are several sub-families.
The Potosinae or kinkajous (Potos) are arboreal vegetable feeders, with a prehensile tail and ventral scent glands; the jaws are massive and the molars flat-crowned.
The Nasuinae or coaitis (Nasua) have webbed feet, with f os sorial claws, a very long tail, an exceedingly mobile probing snout, slender jaws and smaller cheek-teeth than the raccoons but larger tusk-like canines.
The Bassariscinae, the cacomistles (Bassariscus) are active, predacious, genet-like animals with small paws, a long tail and trenchant dentition.
The Bassaricyoninae (Bassaricyon) closely resemble the kinka jous superficially but the tail is not prehensile and the cranial and dental characters are more like those of the raccoons.
Mustelidae.—This family differs from the Procyonidae in the invariable absence of the second upper molar and in the pres ence, except in the sea-otter, of a wide angular emargination, in stead of a notch or slit, between the median and posterior cusps of the upper carnassial. The genera of this family exhibit greater range in structural variation and habits than any family of Car nivora. They are referred to many sub-families, which, setting the otters on one side, may be conveniently assigned to two series.
In the first the upper carnassial is not larger than the molar and has a large inner lobe and a more bluntly cusped blade, and the feet are fossorial.
The Melinae, or badgers, are heavily built, with short legs and tail and a glandular subcaudal pouch. The upper molar is much larger than the carnassial, and the bulla is undivided and does not open into the mastoid. The true badgers (Metes) are found in temperate Europe and Asia and the hog-badgers (Arctonyx) in Burma and southern China.
The Mydainae, containing the teledu (Mydaus), found in Java, Borneo, etc., differs from the badgers in the absence of the sub caudal pouch, the skunk-like development of the anal glands, the disc-like rhinarium, divided upper lip, united toe-pads, reduced ear and the opening of the bulla into the mastoid.
The Taxideinae, or American badgers (Taxidea) are shown by the structure of the skull to be unrelated to the Melinae. The up per carnassial is larger than the molar, the bulla opens into the mastoid, the metatarsus has no pads, the carpal pad is single and peculiar glands are associated with the external genital organs in the male and female.
The Mephitinae, or skunks, restricted to America and repre sented by three genera (Mephitis, Conepatus, Spilogale), are pe culiar in having the mesopterygoid fossa long and the penis with out a bone. There are no special cutaneous glands but the anal glands are excessively developed and their nauseous defensive discharge, associated with the conspicuous pattern and fearless behaviour of the skunks, has made these mammals the stock in stance of warningly coloured species.
In the second series the upper carnassial is never smaller than the molar and has a cutting blade and a small inner lobe.
The Mellivorinae, or ratels (Mellivora), occurring in tropical Asia and Africa, are badger-like in build and habits, but the anus is sunk in a pouch, and its glands are developed as in the skunks, the ear is reduced and the teeth are sectorial.
The Ictonychinae, or African zorillas (Ictonyx, Poecilictis), resemble skunks superficially and differ from Mellivora in being long-tailed, lightly built, more digitigrade, and in having a well developed ear, less sectorial dentition and no circumanal pouch.
The Grisoninae, containing the American Grison and Grison ella, differ from the two preceding sub-families in having the bulla low with the tympanic ring in contact with its roof, and its cavity small and divided. They are superficially like polecats and the offensive discharge of their anal glands is associated with warning coloration.
The Tayrinae. The South American marten-like Tayra differs essentially from the grisons in having the cavity of the bulla inflated, undivided and not communicating with the mastoid. The ear has no marginal bursa, and the feet are naked with con fluent tarsal and metatarsal pads in contact with the plantar pad.
The Martinae, containing the martens and sables (Mantes, Charronia), are found in Europe, Asia and North America. They differ principally from Tayra in having the metatarsus hairy, the carpal pads separated from the plantar pad, small claws and a well developed marginal bursa on the ear. The wolverene (Gulo) is a modified type of this group (q.v.).
The Mustelinae, or stoats (Mustela), weasels (Ictis), polecats (Putorius, Vormela) and other genera occurring in Europe, Asia and America, closely resemble the martens in the structure of their feet but differ from them in the shortness of the muzzle, more sectorial and numerically reduced dentition and in the spongy texture of the wall of the auditory bulla with which the tympanic ring is in contact.
The Lutrinae, or typical otters, represented by many genera (Lutra, Aonyx, Pteronura, etc.), differ from the preceding sub families mainly in their structural adaptations to aquatic life, and particularly in having the hind-feet larger than the fore feet, with long distensible digits. The kidneys also are lobulate. The skull in shape resembles that of the Mustelinae, but the upper molar is as large as the carnassial. The family ranges all 'over the world apart from Madagascar and Australia.
The Enhydrinae, or sea-otter (En/iydris), which is restricted to the North Pacific, differs from the Lutrinae in the structure of the feet. The fore-feet have the digits very short and tightly fused, and the hind-feet very large and paddle-like with the digits progressively increasing in length from the first to the fifth. Also the cusps of the teeth are all bluntly rounded.
The pinnipede arctoids are characterized by the shortness of the upper portion of the limbs and the development of the feet as swimming paddles, especially the hind-feet, which have the first and fifth digits stouter and longer than the rest. The cheek teeth also are all alike. There are three families.
Otariidae.—This family comprises the sea-lions and fur seals; these have small external ears and progress on land in quadru pedal fashion by applying the naked soles of all four feet to the ground. The incisor teeth are present, the canines are of normal size and the cheek-teeth have compressed crowns with one main cusp. They feed mostly on fish. There are seven well-marked species, each of which has received a generic name based on cranial characters. Steller's sea-lion (Eumetopias stelleri) and the northern fur seal (Callonhinus ursinus) are found in the north Pacific ; the Californian sea-lion (Zalophus tali f ornianus) ranges from California to Japan ; the Australian sea-lion (Neo phoea cinerea) inhabits Australia ; the Patagonian sea-lion (0t aria jubata) frequents the coasts of South America; the southern fur seal (Arctocephalus pusillus) occurs in the South American, South African and Australian seas; and Hooker's sea-lion (Pho carctos hookeri), also in the Australian seas. The family is thus restricted to the Pacific and southern oceans.
Odobaenidae.—This family contains the walrus (Odobaenus), restricted to the northern oceans. Its limbs are like those of the Otariidae, but the external ear is absent and the skull is remark ably modified to carry the huge tusk-like upper canines, while the cheek-teeth are flat-crowned for crushing the shells of mus sels and oysters upon which the walrus mainly feeds.
Phocidae.—This family comprises true seals. They are also without external ears, but the hind-limbs are stretched backwards to act as a tail-fin and their soles, which like those of the fore-limb are hairy, are incapable of being applied to the ground. The variation in cranial and dental characters is greater than in the Otariidae, the common seals (Phoca) and the elephant seals (Macrorhinus) exhibiting the extremes. In Phoca the claws are all well developed, the digits of the fore-flippers are subequal and the first and fifth of the hind-flippers only slightly exceed the rest and the integument is not produced beyond their tips; the ,incisors are 3-, the cheek-teeth are cusped and mostly two-rooted, the muzzle is normal, its orifice is small and encircled by the long nasals and premaxillae which are in contact. In Macrorhinus the digits of the fore-flippers decrease in length from the first to the fifth, those of the hind-flippers have no claws and the fourth and fifth digits greatly exceed the rest and are lengthened by skin-lobes; the muzzle of the male is developed into a dis tensible proboscis; the incisors are i , the small cheek-teeth have simple crowns and one root, and the premaxillae and nasals are short and widely separated and do not surround the dilated nasal aperture. Phoca and its allies, e.g., Halichaerus, the grey seal, are found in the northern oceans. Macrorhinus, the largest of the pinnipedes, reaching a length of 20 ft., ranges from the Ant arctic to California; but there are many structurally intermediate genera occurring in the northern and southern oceans.
Fossil remains of the majority of the common modern genera of Carnivora are found in the Pleistocene formations along with a number of extinct types which were known to prehistoric man. Among these the most remarkable are the sabre-tooth tigers or machaerodonts (see MACHAERODUS), the Arctotherium or short faced bear of South America. The great cave-bear of Europe and the giant tiger Felis azrox of North America much exceeded any living species of Ursus and Felis in size ; and the geographic range of hyaenas, lions, Cyon, was then extended to northern Europe, while conversely the wolverine and other northern Carnivora have been found as far south as Arkansas.
All of the families of modern Carnivora are represented in the formations of the later Tertiary epochs, most of them by a wider variety of types than those that survive today, and the ancestry of many of the modern genera can be traced back through the Pliocene, Miocene and Oligocene into or towards a common an cestral stock which appears to be fairly represented by the Eocene family Miacidae of the Primitive Carnivora or Creodonta (see CREODONTA). The Miacidae, alone among the creodont families, have acquired the true carnassial or shearing teeth of the fissiped Carnivora, in the upper and in the lower jaw being enlarged and specialized for this purpose; and on this account they are transferred by some authorities to the Fissipedia. But they have not acquired the consolidated scapholunar bone of the wrist nor the completely ossified auditory bulla of the Fissipedia, and for these and other reasons may best be regarded as pro-fissiped creodonts. (See Matthew, 'gm Memoirs Amer. Mus. Nat. Hist., vol. ix., part vi., pp. In the Oligocene numerous genera of primitive fissiped Carniv ora are known from Europe, North America and Central Asia. They all appear to be rather nearly related, but the beginnings of the distinctions between viverroid, musteloid and cynoid groups can be perceived and the felids are already distinct. The faunas of the three regions have much in common and these Oligocene fissipeds are evidently descended from Holarctic Miacidae of the Eocene. They had apparently not yet reached Africa, although the Creodonta had preceded them into that region, at least as far as Egypt. Neither creodonts nor fissiped Carnivora are found in South America at this time; the Carnivora did not reach the Neotropical region until the Pliocene, their place being taken by carnivorous marsupials in the older Tertiary of South America.
All of these Oligocene Carnivora have the scaphoid and lunar bones united. Most of them have the tympanic ring expanded into a complete bulla, but the bulla is not infrequently loosely artic ulated to the skull and is then usually lost in the fossil specimens.
The cynoid group has the dentition the teeth behind 3•I.4.3 the carnassial moderately reduced and of crushing type. Cynodic tis with only two upper molars leads through a number of inter mediate stages (Nothocyon, Upper Oligocene, Cynodesmus, Lower Miocene, Galecynus and Tephrocyon, Upper Miocene) into the modern Canidae ; while Daphaenus with three upper molars leads (through Daphaenodon of the Lower Miocene) into the Miocene Amphicyons or bear-dogs with enlarged crushing and reduced shearing teeth. These equalled the modern bears in size, but were still largely digitigrade with legs of moderate length and long heavy tail. They are connected with the true bears through Hemicyon (Miocene), Hyaenarctos and Indarctos (Pliocene) in which the teeth progressively assume the fully specialized crushing type of the true bears, the limbs become long and straight, the feet plantigrade and the outer digit of manus and pes the largest. How near this series comes to being a direct line of ances try is not yet settled, but it unquestionably indicates that the bears are derived from primitive Oligocene cynoids. The raccoons also appear to be derived from this primitive cynoid stock, through Cynodon of the Oligocene and Phlaocyon of the Lower Miocene, but it is probable that the modern Procyonidae are several independent parallel branches from this stock rather than a single group.
The Oligocene musteloids have the post-carnassial teeth more reduced than in the cynoids and of more or less cutting type.
Their dental formula is 3 I 4-3.2—I • None of them have acquired 3.1.4-3.2 the expansion of the inner half of m' nor the flattened tympanic bulla that characterize modern Mustelidae ; these characters ap pear in a very rudimentary stage in most of the Lower Miocene and more fully developed in the Middle and Upper Miocene mustelines, but are assumed independently in a number of separate series that lead up more or less directly into the martens, weasels, wolverines, otters, skunks and badgers.
The viverroid group is hardly distinguishable in the Oligocene by tooth characters, but it shows in contradistinction to the cy noids and musteloids a certain tendency to extend the bulla back ward and expand the paroccipital process over its posterior end. The well-developed parastyle on the upper carnassial, character istic of most modern Viverridae and Felidae, is small and incon stant in their Oligocene ancestors, and is moreover not uncom monly found in Tertiary cynoids and musteloids (Aelurodon, etc.) . In the Miocene Viverridae the limitation of the post carnassial teeth to two above and one (the second true molar) below, both well developed, becomes more definite, the bulla more characteristic and the division between viverrine and her pestine genera begins to be distinguishable.
A number of intermediate genera in the Miocene and Lower Pliocene (Ictitlierium, Lepthyaena, Palhyaena) are transitional to the hyaenas, which are fully developed in the Lower Pliocene and are clearly derivable from primitive civets, although the known species of these intermediate genera are not directly an cestral. Hyaenas and civets are found only in the Old World Tertiaries, although fragmentary remains of hyaenoid Canidae from the Tertiary of North America have several times (Aeluro don, Borop/iagus, "Prohyaena," Chasmoporthetes) been mis takenly referred to these Old World families. The Tertiary canids, on the other hand, are chiefly North American, while the Muste lids and ursids are Holarctic.
The Felidae are quite distinct in the Oligocene, and all of them show, but in differing degree, an enlarged and compressed upper canine, reduced lower canine and flanged or angulate chin. They appear to fall into two series ; in one these characters and associated special adaptations in skull and skeleton are decidedly more marked and are progressively increased in the Lower and Upper Miocene to culminate in the Sabre-tooth Tigers of the Pliocene and Pleistocene (see MACHAERODUS). In the other series the above noted peculiarities, already much less developed, are progressively reduced to the nearly normal condition of the modern Felidae in which upper and lower canines are nearly equal, and the chin has lost its flange. The clouded tiger of Malay sia is the most primitive living species in these as in some other particulars. Dinictis of the Oligocene, Nimravus and Archaelurus of the Lower Miocene, Pseudaelurus of the later Miocene, are the successive stages in the ancestry of the Felidae, while Hoplopho neus and Eusmilus of the Oligocene and Machaerodus of the Miocene lead into the more highly specialized sabre-tooths Smilo don and Meganthereon of the Pliocene and Pleistocene. In both the feline and machaerodontine series there is also a progressive specialization of the shearing teeth and reduction of the premolars, these teeth in Dinictis being not far beyond the stage reached in the modern viverrid genus Cryptoprocta. (W. D. M.)