The Living Animals of the World, Volume I: Mammals

Marsupials and Monotremes 379 in number, on their backs, are denizens of tropical South America. One of these, named the

PHILANDER OPOSSUM,

attains to the somewhat larger size of about 2 feet in total length, the long prehensile tail representing, however, the greater moiety of these dimensions.

THE SELVA.

South America has one other marsupial the SELVA an animal which, while possessing the dimensions and much of the aspect of an ordinary rat, is remarkable as differing so materially in the character of its teeth and other structural points that it cannot be referred to any existing marsupial family. On the other hand, this type is found to coincide in the above particulars with species hitherto only known in the fossil state, and excavated from the same tertiary deposits in Patagonia which have been productive of Photo by Dr. R. W. Sliufeldt] the distant ally of YOUNG OPOSSUM (NATURAL SIZE). , as it is reproduced life-size, and gives an excellent idea of the animal in itsthe Tasmanian wolf. This is an interesting photograph native land. It is yet hoped by zoologists that the discovery of other interesting and possibly some supposed extinct mammals may reward the thorough exploration of the vast South American forests. The capture in the flesh of some form allied to the huge ground-sloths, such as the Mylodon and Megatherium, is, however, now considered to be quite beyond the pale of possibility.

of the World38o The Living Animals

MONOTREMES, OR EGG-LAYING

MAMMALS. WITH this group or order of the Mammalian Class we arrive, as it were, on the borderland between the mere typical Mammals and Keptiles. In the last group, that of the Marsupials, it was observed that the young were brought into the world at an abnormally early and helpless phase of their existence, and usually consigned, until able to see and walk, to a variously modified protective pouch. With the Monotremes a yet lower rung in the evolutional ladder is reached, and we find that the young are brought into the outer world as eggs, these being in the one case deposited in a nest or burrow, and in the other carried about by the parent in a rudimentary sort of pouch until they are hatched. The living representatives of this singular mammalian order are but few in number, being restricted, in point of fact, to only two distinctly differentiated family types the Echidna or Porcupine Ant-eater, and the Platypus. These monotremes, moreover, like the majority of

Photo by W. Saville-Kcnt, F.Z.S.] [Milford-oii-tiea. the existing marsupials, are limited in their WOOLLY AMERICAN OPOSSUM. distribution to the Australasian region. TheThis animal is about the size of a large mouse. It carries its young on its back, their tails being entwined round that of their parent. single species of the Platypus is only found in Tasmania and the southern and eastern districts of the Australian Continent, while the Echidna numbers some three recognised species, two of which belong to Australia and Tasmania and the third to New Guinea.

THE ECHIDNA.

The ECHIDNA, PORCUPINE ANT-EATER, or "PORCUPINE," as it is commonly called by the Australian colonists, would seem at first sight to represent an animal in which the characters of the hedgehog and the common porcupine are interblended, the innumerable spines being longer than those of the former, but less in length than those of the last-named animal. The head, with no externally visible ears and remarkable elongated beak-like snout, however, at once proclaims it to be altogether distinct from these. The animal has no teeth, and the tiny mouth at the termination of the beak-like snout simply constitutes an aperture for the extrusion of the worm-like glutinous tongue, wherewith, after the manner of the true ant-eaters, it licks up the inhabitants of the ants' nests upon which it feeds. For tearing down the ants' nests and obtaining its customary food, as also for its inveterate burrowing propensity, the feet, and more especially the front ones, are provided with strong, blunt, and very powerful claws. The male animal is in addition armed on the hind feet with a peculiar supplementary spur, which is, however, still more conspicuously developed in the platypus.

Three distinct species of the echidna are recognised by zoologists. The one peculiar to the cooler climate of Tasmania is remarkable for its more slender spines, the much greater abundance of the long bristle-like hairs, and the thickness of the seal-brown under-fur, as compared with the typical Australian form. In North-west New Guinea the largest and most aberrant form is met with. Normally it has only three toes in place of five to each foot, the spines are very long and thick, the body is deeper and more compressed, and the animal stands comparatively high upon its feet.

Marsupials and Monotremes 381

The writer, during his residence in Tasmania, had several examples of the local species as domestic pets. For the first few days they were very shy and untractable, burrowing into the earth and seeking to escape, or presenting an impenetrable chcval de frise of sharp-pointed spines to the hands that sought to caress them. After a short interval, however, the creatures became entirely reconciled to human society and the small amount of restraint to which they were subjected. They would follow their owner about the garden, or, flattening their bodies and spreading out their limbs to the greatest extent, lie basking in the sun close to where he might be seated. They also apparently appreciated being carried, slung across their owner's arm after the manner of a lap-dog. Living in the near vicinity of unreclaimed bush-land, it was found possible to keep these echidnas well supplied with their customary food; they were, in fact, permitted to forage on their own account. Liberated amidst their normal surroundings, they would walk leisurely from one ant-hill to another, tearing down the side of it with their powerful front claws, and appropriating its living contents with the greatest relish. It was observed, however, in this connection that the echidna paid attention entirely to the succulent white larvae and pupal phases of the insects with which the inner chambers of the ant-hills are customarily crowded, and that adult ants, as they abounded in the tracts near at hand or elsewhere, were altogether neglected. In addition to this natural food these animals were supplied daily with a saucer of either well-softened bread or porridge and milk, for which they evinced a decided appreciation, assimilating this food dexterously, though somewhat slowly, with the aid of their long protrusile tongues. Allowed to wander about the house, they displayed a most inquisitive turn of mind, peering into every crevice, and climbing upon every accessible article of furniture.

The echidna usually produces only one egg at a time; it is relatively small, not larger than a sparrow's egg, but equally and obtusely rounded at both extremities, and with a white is carriedleathery shell like that of a reptile. For some time previous to hatching, this egg in a skin-fold or rudimentary pouch in the parent's abdomen, much similar to that possessed is also retained in this pouch for some weeksby many of the marsupials. The young one it is between three and fourafter escaping from the egg. When finally leaving the pouch, inches in length, and the spines are in an altogether rudimentary condition.

Examples of the Australian echidna have on several occasions been " in residence " at the Zoo; while the Hon. Walter Rothschild has been fortunate in keeping living specimens of both this and the very rare three-toed New Guinea variety in his admirably appointed menagerie at Tring.

THE PLATYPUS.

The egg-laying mammal known as the DUCK-BILLED PLATYPUS differs very essentially from the echidna both in aspect and habits. It is adapted especially for an amphibious life, and for feeding on molluscs, worms, and insects, which it abstracts from the muddy bed or banks of the rivers that it frequents. isThe somewhat depressed ovate body covered with short dense fur much resembling in colour and texture that of an otter. The tail is short and flattened like that of a beaver, but in place of rhotobyW.saviae-Kc,it,F.z.a.} being naked and scaly, as in that animal, COMMON OR VIRGINIAN OPOSSUM. animal found north of Mexico.is COVered, On the Upper Surface more The only marsupial

of the World382 The Living Animals

particularly, with long, coarse, bristle-like hairs that intercross one another in all directions. Neither is this tail used, as with the beaver, as a mason's trowel, it being simply subservient as a steer-oar. The feet are all four distinctly webbed, the membranes of the front feet in particular projecting to some distance beyond the extremities of the claws, and so communicating to these members a singular resemblance to the feet of a duck. The head of the platypus tapers off from the body without any conspicuous neck, and terminates in a most remarkable duck-like beak, having at its base a supplementary membranous ferrule-like structure which would seem to serve the purpose of limiting the distance into which the beak of the for its accustomed food, and at the sameanimal is thrust into the mud during the quest time protecting the creature's eyes. The mouth of the adult platypus contains no teeth, simply a few horny plates; but, singularly to relate, rudimentary teeth exist temporarily in the young animals. These provisional teeth, moreover, correspond in a marked manner with those of some ancient types of mammals which occur as fossils in the tertiary deposits of North America. The platypus, with relation to the obliteration of its teeth in the adult state, is regarded as a very exceptionally modified form and not as the immediate prototype of the ordinary mammals. is found in Tasmania and in the south and eastern districts of Australia The platypus only, being altogether unknown in the west and north. Being especially shy and retiring, and to a large extent nocturnal in its habits, it is not frequently seen even in districts where it may be rather abundant. The animal excavates burrows of so great a length as from thirty to fifty feet in the river-banks that it frequents, and at the extreme end of these burrows it constructs a loose nest of weeds and root-fibres, which it uses as its retreat, and also for the production of its eggs and young. There are invariably two entrances to these burrows, the one being under water, and the other usually opening into a tangle of brushwood at some little distance from the water's edge. As many as from one to four eggs and young may be produced at a time, but two is the more general number. From the first it would appear that the eggs and young are deposited and nursed in the nest, not being retained or carried about in a pouch, as observed of the echidna.

The late Dr. George Bennett, of Sydney, New South Wales, has probably placed on record it didthe most detailed account of the ways and life-habits of these remarkable animals, though not fall to him to solve the much-vexed question as to whether or not they were oviparous. This discovery, as applied also to the like phenomenon in the case of the echidna, was the outcome within quite recent years of the researches of Mr. Caldwell. After much indefatigable exploration, in which he was ably assisted by the natives, Dr. Bennett obtained from the extremity of an exceptionally long burrow a mother and pair of half-grown young. The young ones survived several weeks, and proved most droll and interesting pets. In playful habits they much resembled puppies, chasing and rolling one another over, and pretending to bite with their toothless bills. They were also much addicted to climbing every scalable article of furniture, including even a tall book-case, which they would negotiate by "swarming" up behind it as a sweep climbs a chimney,