kangaroos species molars hind limbs true australia incisors premolars upper
KANGAROO. When captain Cook, during his first memorable voyage of discovery, was detained, for the purpose of refitting his ship at Endeavour river, on the north-east coast of Australia, a strange-looking animal, entirely unknown to them, was frequently seen by the ship's company; and it is recorded in the annals of the voyage that, on the 14th of July 1770, " Mr Gore, who went out this day with his gun, had the good fortune to kill one of the animals which had been so much the subject of our speculation, . . . and which is called by the natives kanguroo," I a name which, though it does not appear to be now known to any of the aboriginal tribes of the country, has been adopted for this animal in all European languages, with only slight modifications of spelling. With the exception of a passing glimpse in the beginning of the same century by the Dutch traveller Brnyn of some living examples of an allied species, to be referred to presently, this was the first introduction to the civilized world of any member of a group of animals now so familiar. The affinities of the species, skins of which were brought home by Captain Cook and subsequent voyagers, were recognized by Schreber as nearer to the American opossums (then the only known intrsupials) than to any other mammals with which zoologists were acquainted, and consequently it was placed by him, in his great work on the Mammalia, then in the course of publication, in the genus Didelphis, with gigantea for a specific designation, - the latter having been bestowed upon it by Zimmerman under the impression that it was a huge species of jerboa. Soon afterwards (1791) Dr Shaw very properly formed a new genus for its reception, which he named 3facropus, in allusion to the peculiar length of its hind foot. By the name thus formed, Afacropus giganteus, this kind of kangaroo has ever since been known in zoological literature.
Further explorations in Australia and the neighbouring islands have led to the discovery of a very considerable number of species, which are now included in the family Macropodidie, one of the subdivisions of the order Alarmpialia, for the characters of which see MAXMALIA.
The Macropodida, or kangaroos, taken as a whole, form a very well marked family, easily distinguished from the remaining members of the order by their general conformation, and by peculiarities in the structure of their limbs, teeth, and other organs. They vary in size from that of a sheep down to a small rabbit. The bead, especially in the larger species, is small, compared with the rest of the body, and tapers forward to the muzzle. The shoulders and fore limbs are feebly developed, and the hind limbs of dispro portionate strength and magnitude, which gives them a peculiarly awkward appearance when moving about on all fours, as they occasionally do when feeding. Rapid progression is, however, performed only by the powerful hind limbs, the animal covering the ground by a series of immense bounds, during which the fore part of the body is inclined forwards, and balanced by the long, strong, and tapering tail, which is carried horizontally backwards. When not moving they often assume a perfectly upright position, the tail aiding the two hind legs to form a sort of supporting tripod, and the front limbs dangling by the side of the chest. This position gives full scope for the senses of sight, hearing, and smell to warn of the approach of enemies, from which they save themselves by their bounding flight. The fore paws have five distinct digits, each armed with a strong, curved claw. The foot of the hind limb is quite different, and very peculiar in construction, being extremely long and narrow, and (with only one, lately discovered, exception) without any hallux or great toe. It consists mainly of one very large and strong toe, corresponding to the fourth of the human or other typically developed foot, ending in a strong curved and pointed claw. Close to the outer side of this lies a smaller fifth digit, and to the inner side two excessively slender toes (the second and third), bound together almost to the extremity in a common integument. The two little claws of these toes, projecting together from the skin, may be of use in scratching and cleaning the fur of the animal, but the toes must have quite lost all connexion with the functions of support or progression.
The dental formula, when completely developed, is incisors 1, canines 11,-, premolars molars 4- on each side, giving a total of thirty-four teeth. The three incisors of the upper jaw are arranged in a continuous arched series, and have crowns with broad cutting edges ; the first or middle incisor is often larger than the others. Corresponding to these in the lower jaw is but one tooth on each side, but it is of great size, procumbent or directed horizontally forwards, narrow, lanceolate, pointed, and with sharp edges. Owing to the laxity of the union of the two rami of the lower jaw at the symphysis, in many species the two lower incisors can be made to work together like the blades of a pair of scissors, a very remarkable arrangement not known to occur in other mammals. The canines are absent or rudimentary, always so in the lower jaw, and often deciduous at an early age in the upper jaw. The premolars are compressed, with cutting longitudinal edges, the anterior one is always deciduous, being lost about the time the second one replaces the milk molar, so that both premolars are never found in place and use in the same individual. The true molars have quadrate crowns, provided with two strong transverse ridges, or with four obtuse cusps. In Macropus giganteus and its immediate allies, both premolars and one or two of the anterior true molars are shed during the lifetime of the animal, so that in old examples only the two posterior molars and the incisors are found in place. The milk dentition, as in other marsupials, is confined to a single molar tooth on each side of each jaw, the other molars and incisors being never changed. The dentition of the kangaroos, functionally considered, thus consists of sharp-edged incisors, most fully developed near the median line of the mouth, for the purpose of cropping the various kinds of herbage on which they feed, and ridged and tuberculated molars for crushing it, there being no tusks or canines for offensive or defensive purposes.
The number of vertebrae is - in the cervical region 7, dorsal 13, lumbar 6, sacral 2, caudal varying according to the length of the tail, hut generally from 21 to 25. In the fore limb the clavicle and the radius and ulna are well developed, allowing of considerable freedom of motion of the hand. The pelvis has large epipubic or " marsupial " bones. The femur is short, and the tibia and fibula of great length, as is the foot, the whole of which is applied to the ground when the animal is at rest in the upright position.
The stomach is of large size, and very complex, its walls being puckered up by longitudinal muscular bands into a great number of sacculi, like those of the human colon. The alimentary canal is long, and the ccum well developed. All the species have a marsupium or pouch formed by a fold of the skin of the abdomen, covering the mammary glands with their four nipples. In this pouch the young (which, as in other marsupials, leave the uterus in an extremely small and imperfect condition) are placed as soon as they are born ; there their growth and development proceeds ; and to it they resort temporarily for the purpose of shelter, concealment, or transport, for some time after they are able to run and jump about the ground and feed upon the same herbage which forms the nourishment of the parent. During the early period of their sojourn in the pouch, the blind, naked, helpless young creatures (which in the great kangaroo scarcely exceed an inch in length) are attached by their mouths to the nipple of the mother, and are fed by milk injected into their stomach by the contraction of the muscle covering the mammary gland. In this stage of their existence the respiratory organs are modified much as they are permanently in the Cetacea, the elongated upper part of the larynx projecting into the posterior nares, and so maintaining a free communication between the lungs and the external surface, independently of the mouth and gullet, thus averting all danger of suffocation while the milk is passing down the latter passage.
The kangaroos are all vegetable feeders, browsing on grass and various kinds of herbage, the smaller species also eating roots. They are naturally timid, inoffensive creatures, but the larger ones when hard pressed will turn the sharp claws of their powerful hind legs, sustaining themselves meanwhile upon the tail. The great majority are inhabitants of Australia and Tasmania, forming one of the most prominent and characteristic features of the fauna of these lands, and in the scenery of the country, as well wanting in Australia. They were very important sources of food-supply to the natives, and are hunted by the colonists, both for sport and with a view to their destruction, on account of the damage they naturally do in consuming the grass, now required for feeding cattle and the Australian province, beyond the bounds of which none have been found either existing or in a fossil state.
The Maeropodidx are divided into two well-marked sections--(1) the true kangaroos (Macropodinx), and (2) a group consisting of smaller animals, commonly called rat-kangaroos, or (improperly) " kangaroo-rats," or sometimes potoroos.
I. In the Nacropodinte (see fig. 3) the cutting edges of the upper incisors are nearly level, or the first pair but slightly longer than the others. The canines are rudimentary and often wanting. The premolars are usually not longer (from before backwards) than the true molars, and less compressed than in the next section. The crowns of the molars have always two prominent transverse ridges. The fore limbs are small with subequal toes, armed with strong, moderately long, curved claws. Hind limbs very long and strongly made. Head small, with more or less elongated muzzle. Ears generally rather long and ovate.
Upwards of thirty species of this group have been described, and many attempts have been made to subdivide it into smaller groups or genera for the convenience of arrangement and description, but these have generally been based upon such trivial characters that it is preferable to speak of most of them as sections of the genus Macropus, reserving generic rank only to two forms somewhat aberrant both in structure and geographical distribution. According to this arrangement the genera will be as follows :- ruficollis, AL ualabatus, bf. dorsalis' Ai. egilis, derbianus, thetiells, AL billardieri are the best known. AL brachyurus is remarkable for its comparatively short and slender tail and small ears. The earliest known species of kangaroo, referred to before, AI. brunii (Schreber), may perhaps belong to this section. Several examples were seen by Bruyn in 1711 living in captivity in the garden of the Dutch governor of Batavia, and described and figured in the account of his travels (Reizen over Moskovie, &c.) under the name of " Filander." It was quite lost sight of, and its name even transferred by S. Muller to another species (now known as Doreopsis miilleri, Schlegel) until rediscovered in 1865 by Rosenberg, who sent a series of specimens to the Leyden Museum from the islands of Amu and Great Key, thus determining its true habitat. Quite recently three other species of true kangaroo have been discovered out of Australia:-211 papuanus, Peters, from the eastern extremity of New Guinea, near Yule Island; Af. erassipes, Pierson-Ramsay, from near Port Moresby ; and Al. browni, Pierson-Ramsay, from New Ireland. D. Onychoyalea, Gould, with a hairy muffle and long and slender tail, furnished with a horny nail-like organ at the apex. AI. ainguifer, AI. frtenalus, and AL lunatus. E. Lagorchestes, Gould, hare-kangaroos, a group of small hare-like animals, great leapers and swift runners, which mostly affect the open grassy ridges, particularly those of a stony character, sleeping in forms or seats like the common hare. Their limbs are comparatively small, their claws sharp and slender, and their muffle clothed with velvet-like hairs. 1. faselatus, 16i. loperoides, AL Airmails, M. conspieillabus, &c. F. Petrogale, Gray. These differ from all the others in having the tail cylindrical and bushy towards the apex instead of tapering. The muffle is naked, the hind foot comparatively short and stout, and densely clothed with coarse hairs, the nails short. These are the "rock kangaroos," making their retreats in caverns and crevices, leaping with surprising agility from one narrow ledge to another, and browsing upon the scanty herbage that the neighbourhood of such situations affords. .11f. xauthopus, 11f. penicillatus, M latcralis, Al. COILCi111111.8, 11f braehyotus, M. inornatus, Dendrolagus, Sal. Miiller. - A genus formed for the reception of two species, D. ursinus and D. inustus, commonly known as " tree kangaroos," both inhabitants of New Guinea, and which differ greatly from all the foregoing in being chiefly arboreal in their habits, climbing with facility among the branches of large trees, and feeding on the bark, leaves, and fruit. In accordance with this habit their hinder limbs are comparatively shorter than in the true kangaroos, and their fore limbs are longer and more robust, and have very strong curved and pointed claws. These differ from all the preceding, and agree with the next genus, in some details of the structure of the molar teeth, and in the circumstance that the fur of the back of the neck is directed forwards or in a reverse position to that of the remainder of the coat.
Dorcopsis, S. Mtiller. - Of this genus two species are at present known, both from New Guinea, D. multeri, and another lately discovered by D'Albertis, D. luetuosa. . In some respects they resemble the last, but they differ from them and all the other Afaeropodime, and agree with the next section, in the great size and peculiar form of the premolar teeth.
II. The second section or sub-family, the frypsiprymninx (see fig. 4), have the first upper incisor narrow, curved, and much exceeding the others in length. Upper canines always persistent, flattened, blunt, and slightly curved. Premolars of both jaws always with large, simple, compressed crowns, with a nearly straight or slightly concave free cutting edge, both outer and inner surfaces usually marked by a series of parallel, vertical grooves and ridges. Molars with quadrate crowns, having a blunt, conical cusp at each corner, the fourth notably smaller than the third, sometimes rudimentary or absent. Fore feet narrow; three middle toes considerably exceeding the first and fifth in length ; their claws long, compressed, and but slightly curved. Hind feet as in Afacropus. Tail long, sometimes partially prehensile, being used for carrying bundles of grass with which they build their nests.
The potoroos or rat-kangaroos are all small animals, none of them exceeding a common rabbit in size. They inhabit Australia and Tasmania, are nocturnal, and feed on the leaves of various kinds of grasses and other plants, as well as roots and bulbs, which they dig up with their fore paws. About ten species are known, presenting a considerable range of diversity in minor characters, and admitting of being grouped in four principal sections, which may perhaps be allowed the rank of genera. These are Hypsiprymnus, Illiger. - Head long and slender. Auditory hallw somewhat inflated. Ridges on premolars few and perpendicular. Large palatine foramina. Tarsus short. Muffle naked. Ii. murinus, H. apicalis, H. gilberti, H. platyops.
Bettongia, Gray. Head comparatively short and broad. Auditory bulln much inflated. Tarsus long. Large palatine foramina. Ridges on premolars numerous and oblique. Muffle naked. B. penicillatns, B. euniculus, B. gaimordii, B. ogilbyi, B. grayii, B. campcstris, &c.
zgpyinynnus, Garrod. - Head short and broad. Auditory bulhe not inflated. No palatine foramina. Tarsus long. Muffle hairy. IE. rnfescens.
In seeking among the other marsupials for the nearest allies to the kangaroos, using this word in the •omprehensive sense as above, two most striking points in their organization must be borne in mind, the structure of the hind foot and the dentition. Of the former the essential peculiarity is the great predominance of the fourth digit, and the remarkable character of the second and third, which while retaining a considerable length, are of extreme tenuity, and buried up to the claws in a common integument. Snell a structure of foot is quite unknown out of the marsupial order, but in that order it is found in the Phalangistidx in a very modified form, associated with a large opposable hallux, and a broad sole of the foot,„ appropriate for climbing trees ; and again, in almost the same form as in the kangaroos, in the ground-dwelling Peramelidm, which in their dentition and digestive organs are so widely different. The Australian carnivorous marsupials, Dasyuridw, and the American opossums or Didelphida, show no trace of this singular conformation. It is therefore only with the former families, the Phalangistidm and the Peramelidx, that the kangaroos are allied by this character.
The chief peculiarity of the dentition consists in the presence of three pairs of incisors in the upper jaw, the first or middle one of which is generally the largest, opposed to a single pair in the lower jaw, strong, sharp, and procumbent. These are followed by an interval, in which may be, in the upper jaw only, a canine, but always so small, as to be of little functional importance. The premolars are compressed and cutting, and the true molars ridged or tuberculated. Such a dentition is found among the Phalangistidx alone of existing marsupials. In this respect the Peramelidm are completely separated from the kangaroos, their numerous small incisors, large canines, and cuspidated molars resembling those of the Dasyuridce and Didelphidx. On the whole then, the kangaroos and the phalangers are groups most nearly allied in essential characters, having both dentition and extremities formed upon the same fundamental type, though with modifications of the latter to snit their respective terrestrial and arboreal habits.
Remains of numerous extinct species of true kangaroos, many of them of much larger size than any now existing, are abundant in the Pleistocene deposits of Australia, and have been described and figured by Professor Owen in the Philosophical Transactions. Hitherto they have been found in no other part.of the world. Other animals of gigantic size, the Diprotodon, as large as a rhinoceros, and the Sototherium, but little inferior, with dentition of the same general type, but the structure of whose feet is not yet known, lived with these kangaroos in the same land. An extraordinary modification of the Ilypsipryninus type, with the great premolar characteristic of that genus immensely exaggerated in size, and the true molars equally reduced, misnamed Thylacoleo carnifex, was another contemporary. Beyond these, which all belong to the most recent geological epoch, we have no knowledge. of any extinct animals which can be said to be nearly allied to kangaroos, or to connect them with any other forms of mammals. The only marsupials discovered in European Tertiaries resemble the existing opossums of America, and except in their common marsupial characters have no affinities with the kangaroos.
It is, however, a most remarkable fact that in the Pinjaws of small mammals (to which Dr Falconer gave the affinity of the still more ancient Ilypsiprymnopsis (Boyd would carry back the type to an extraordinary antiquity.
Literatirrc. - G. R. Waterhouse, Kat. Hist. of the PTammaUa, vol. i., " Marsupiata," 1846; J. Gould, Mammals of Australia; R. Owen, article "Marsupialia " in Cyclop. of Anatomy and Physiology ; various memoirs " Ou Extinct Mammals of Australia " in Philosophical Transactions; " Mesozoic Mammalia," Paixonto. graphical Society, 1871; H. Falconer, " On Plagiaulax," Quart. fourn. Geol. Soc., August 1857 and November 1862; W. H. Flower, "On the Development and Succession of the Teeth in the Marsupialia," Phil. Trans., 1867; " On the Affinities and Probable Habits of Thylacolco," Quart. Journ. Geol. Soc., August, 1868; A. H. Garrod, " On .Dorcopsis luctuosa and its Affinities," Proc. Zool. Soc., 1875, p. 48. (W. H. F.) • KANGRA, a district in the lieutenant-governorship of the Punjab, India, lying between 31° 20' and 33° N.
Doabs, across two distinct Himalayan ranges, far into the heart of Thibet. It naturally falls into three parts - the sub-Himalayan country of Kangra proper, the central valleys of Kullu and Bangahal, and the rugged outer region of the verse ridge, form four main basins, in each of which a great comparatively dense population ; while the bare and sterile eastern glens are sparsely inhabited by a Tibetan race.
The census of 1868 disclosed a population of 743,882 (393,571 males and 350,311 females),-83 to the square mile. The Hindus numbered 693,505; Mahometans, 48,613; Sikhs, 1314 ; Christians, 277; and " others," 173. The six municipal towns with their population are - Ninpur, 7151 ; Kingra, 6344 ; Haripur, 3839 ; Sujanpur Tira, 3393 ; Jaw6.1a-mukhi, 2847 ; Dliarmsala, 2024. The famous Hindu temple. of NAgarkot at Kiingra town is one of the oldest and most wealthy shrines in India, and twice exposed the district to the plunder of the Mahometans.
The cultivated area of the district is returned at 681 square miles, or less than one-thirteenth of the entire surface. The staple crops include wheat and barley for the spring; and rice and maize for the autumn harvest. Rice is the principal crop of the upper valleys, while maize composes the ordinary food of the upland people for six months of the year. Sugar-cane covers a large area in the neighbourhood of Kiingra town. Tea cultivation has taken root as an important industry, both in Kangra proper and in Kullu. In 1872-73 the district contained twenty-eight plantations, producing a gross out-turn of 428,655 lb of tea, valued at £65,000. Potatoes also constitute a considerable crop. In LahL and Spiti barley is the agricultural staple ; but the former tract does not grow a sufficient quantity of grain for its own consumption, being largely supplied by importations from Kullu.
Agricultural produce forms the staple of the export trade ; the imports consist of grain, cotton, tobacco, and European piece goods. The Palampur fair, established by Government with a view to fostering commerce with Central Asia, draws together a small concourse of Yarkandi merchants. The LalrLis carry on an enterprising trade with Ladakh and countries beyond the frontier, by means of pack sheep and goats. The total imperial revenue in 1872-73 amounted to £71,434, of which the land-tax contributed £62,443. Crime is rare, but education is still in a very backward state, only 2936 children being under instruction in 1872-73. The endemic diseases of the district include fever and goitre, but scurvy also prevails to a large extent. The widespread cultivation of rice, by which the whole Kangra valley is converted into a swamp, has a very prejudicial effect upon the general health. The average annual rainfall varies from 148 inches at Dharmsala to 76 at Ktingra, 52 at Hamirpur, and 108 at Palampur. The mean temperature in the Himalayan station of Dharmsala, in 1874-75 was 70'35 in May, 73•5 in July, and 52°•85 in December.