14 



MUSEUM OF ANIMATED NATURE. 



[Opossums. 



MAESUPIALIA. 



Most zoologists of the present day, and among them 

 the "first comparative anatomists, concur in regard- 

 ing the marsupial animals (Marsupialia or Marsu- 

 piata*) as a distinct group, or sub-class of the 

 Mammalia. They differ essentially from all others 

 in their organization, yet comprehend genera fed 

 by every variety of nutriment. Some are insecti- 

 vorous or carnivorous, others herbivorous, and others 

 again frugivorous; some are diurnal, others noc- 

 turnal in the habits. Accordingly we find a cor- 

 responding modification of the teeth and • digestive 

 organs, as well as of those of progression and pre- 

 hension. Hence may we trace in them analogies 

 to the groups of the ordinary mammiferous quadru- 

 peds, viz., to the Carnivora, the Insectivora, the Ro- 

 dents, and the Edentata, as was well observed by 

 Cuvier, whose opinions have been abundantly con- 

 firmed. It is on physiological grounds that. the. 

 distinctness of the Marsupials rests, that is, on their 

 structure and economy connected with the repro- 

 duction of their species, on the abbreviated term of 

 gestation, and on the immature condition of the young 

 at their birth, which are generally received into the 

 marsupium or pouch, in which nidus the unde- 

 veloped being attaches itself to the teats, receives 

 nutriment, and grows, till at length it is ca,pable of 

 acting for itself. In some instances the marsupium 

 is nothing more than a fold of skin, and some- 

 times it is wanting ; but two bones, situated on 

 the anterior part of 'the pelvis, and termed the mar- 

 supial bones, are never absent. These grounds of 

 distinction have been extended by the researches of 

 anatomists, and among them in particular Professor 

 Owen, who has pointed out several never-failing 

 accordances in the structure of other organs, as the 

 heart and the brain, and also has cleared up many 

 points respecting which doubts had previously ex- 

 isted. Into the' series of facts and deductions so 

 luminously treated by that philosophic investigator 

 of nature the plan of this work forbids us to enter : 

 we refer our readers, however, to the ' Phil. Trans.,' 

 part ii., 1834; the 'Proceed. Zool.Soc. Loud.,' 1831, 

 1833, 1838, and 1839 ; 'Phil. Trans.,' part i., 1837; 

 « Annals of Nat. Hist.,' Nov., 1839 ; 'Proceed. Geol. 

 Soc. Lond.,' vol. hi., 1838-9, &c. 



The Marsupial animals are ail restricted to two 

 portions of the globe, namely, America and Aus- 

 tralia, including certain islands of the Indian Ar- 

 chipelago. The American species were the first 

 known to European naturalists, and, indeed, the 

 only ones with which Linnaeus was acquainted. 

 Captain Cook introduced the kangaroo of Australia 

 to science, and subsequent researches in that re- 

 gion, the newest continent, have made us now 

 familiar with its Fauna and Flora. Upwards of 

 seventy species of Marsupials are known as_ Aus- 

 tralian, besides about eighteen species belonging to 

 other groups of quadrupeds, as the dingo dog, cer- 

 tain seals, a few bats, and Rodents. The marsupial 

 sub-class contains the following families, viz. : 

 1. Didelphidse. 2. Dasyuridae. 3. Myrmecobiidas. 

 4. Peramelidse. 5. Macropidae. 6. Phalangistidse. 

 7. Phascolomyidse. 8. Mo'notremata. Of each of 

 these family sections we shall give examples. 



OPOSSUMS. 

 60, 61. — The Virginian Opossum 

 'Didelphis Virginiana). The genus Didelphis, of 

 which the Virginian opossum is an example, is 

 restricted to America. It contains about twenty 

 species, some of which are very small. 



The teeth are as follows : — upper incisors ten, of 

 which the two middle are longer than the rest, _ and 

 somewhat separated from them ; lower incisors 

 eight ; canines as usual ; molars on each side above, 

 seven, the three first false, triangular, compressed ; 

 molars below, seven, the three first false ; the true 

 molars both above and below crowned with sharp 

 tubercles. Of all terrestria mammalia, the Myrme- 

 cobius excepted, the teeth are in these animals 



the most numerous, amounting to fifty : Incisors _ > 



b 



canines 1 — , molars 5=^ = 50. (See figure 62.) 



1—1 7—7 



The limbs are short, the feet plantigrade, the toes 

 five on each foot, armed with sharp strong curved 

 claws, excepting the inner toe or thumb on the 

 hinder feet, which is opposable, and destitute of a 

 nail. The soles are covered with a naked skin en- 

 dowed with great sensibility. The tail is scaly and 

 naked, except at its base, and constitutes an organ 

 of prehension, not, however, to the same extent in 

 every species. The head is long and pointed, the 

 profile straight, The eyes are small, dark, promi- 

 nent, and undefended by eyelids, but furnished 

 with a nictitating membrane.. The ears are large, 

 thin, naked, and rounded. The tongue is rough 

 with horny papillae. The snout is long ; the muzzle 



* Marsupium, a purse or pouch. 



pointed, naked, and moist ; the nostrils are lateral ; 

 the mouth extremely wide ; and the expression of 

 the physiognomy. peculiar and unpleasant. In one 

 division of this genus the females have a pouch for 

 their young ; in another division the pouch is rudi- 

 mentary, consisting of a slight fold of skin. 



In the figure (63) of the skeleton of the Virginian 

 opossum, the marsupial bones (uj are seen. 



The Virginian opossum, and its immediate rela- 

 tives, are slow in their movements, and nocturnal 

 in their habits ; they reside habitually on the 

 branches and in the hoRows of trees, remaining 

 torpid during the day. At night they prowl about, 

 and feed upon insects, eggs, birds, reptiles, and 

 small mammalia, adding also fruits and roots to 

 their diet. Their sense of smell is in high perfec- 

 tion. Like our pole-cat, as respects voracity, though 

 not activity, they often invade the precincts of the 

 farm-house, destroy poultry and other domestic birds, 

 and retreat on the first appearance of dawn, leaving 

 their slaughtered victims behind. Their odour is 

 disgusting, especially when alarmed or irritated. 



The Virginian opossum is common in many parts 

 of North America, from Mexico to the southern 

 provinces of the United States. It is one of the 

 largest and most robust of the genus, and equals a 

 cat in size, being about twenty-two inches in the 

 length of the head and body measured over the 

 curve of the back ; the tail is fifteen inches long. 

 The under fur is deep and woolty, traversed by 

 long straight whitish hairs, often tipped with brown. 

 The ears are large and black, margined at the tip 

 with white. The scaled portion of the tail of a 

 whitish tint. The general colour of the fur is dirty- 

 white, with a slight yellow hue ; the legs are dusky- 

 brown, a tint of which surrounds the eyes. Hairs 

 of moustaches long and white, with a few of a black 

 colour intermixed. 



There is notliing pleasing either in the appear- 

 ance or habits of the Virginian opossum : in cap- 

 tivity it is slothful in the extreme, and becomes 

 inordinately fat, eating both animal and vegetable 

 diet. Whatever may be its cunning in a state of 

 liberty, it evinces but little intelligence when caged 

 in our climate, but appears to be a. compound of 

 indolence and apathy, not unmixed with timidity. 

 In its native woods it suffers from the attacks of 

 birds and beasts of prey, and is also hunted by man 

 for the sake of the flesh and fat. " As soon as the 

 opossum discovers the approach of his enemies, he 

 lies perfectly close to the branch, or places himself 

 snugly in the angle where two limbs separate from 

 each other. The dogs, however, soon announce the 

 fact of his presence by their baying, and the hunter, 

 ascending the tree, shakes the branch upon which 

 the animal is seated with great violence, so as to 

 alarm and cause him to relax his hold." In this 

 way, driven from branch to branch, he is obliged 

 at last to drop to the ground, where, unless the dogs 

 are vigilant, the animal escapes ; for, as is asserted, 

 it steals slowly and quietly to a little distance, and 

 gathering up "itself into a small compass, assumes 

 the stillness and attitude of death. This artifice, 

 under the obscurity of night, and amidst dense rank 

 herbage, or tangled underwood, often proves suc- 

 cessful. In the ' Perfect Description of Virginia,' 

 1649, it is noticed as a beast " that hath a bagge 

 under her belly, into which she takes her young 

 ones, if at any time affrighted, and carries them 

 away." Lawson states that the 'Possum is found 

 nowhere but in America. She is the wonder of all 

 the land animals, being the size of a badger, and 

 near that colour. The female doubtless breeds her 

 young at her teats, for I have seen them stick fast 

 thereto, when they have been no bigger than a 

 small raspberry, and seemingly inanimate. She 

 has a paunch or false belly, wherein she carries her 

 young, after they are from those teats, till they can 

 shift for themselves. Their food is roots, poultry, or 

 wild fruits. They have no hair on their tails, but a 

 sort of a scale, or hard crust, as the beavers have. 

 If a cat has nine lives, this creature surely has nine- 

 teen ; for if you break every bone in their skin, and 

 mash their skull, leaving them for dead, you may 

 come an hour after, and they will be gone quite 

 away, or perhaps yjQl may meet them creeping 

 away. They are a very stupid creature, utterly- 

 neglecting their safety. They are most like rats of 

 anything. I have, J0v necessity in the wilderness, 

 eaten of them. Their flesh is very white, and well 

 tasted ; but their ugly fails put me out of conceit 

 with that fare. Theylffimb trees as the racoons do. 

 Their fur is not esteemed nor used, save that the 

 Indians spin it into girdles and garters." The pre- 

 hensile power of the t£il serves the animal in 

 more ways than one, for it is stated that the little 

 ones when advanced in* growth leap upon their 

 mother's back if they are'frightened, and, twisting 

 their tails round hers, escape, with her assistance, 

 the threatened danger. * 



This animal climbs wilii great facility, and will 



hang suspended from the, branches by its tail, and 



1 by swinging its body contrive to fling itself to the 



adjoining boughs. It is often observed hanging 

 motionless tor a considerable time with its head 

 downwards. 



The opossum produces several young, sometimes 

 as many as sixteen at a birth. She. makes a thick 

 nest of dry grass, in some obscure retreat, in which 

 to conceal herself. When first born the young are 

 in a most rudimentary state, minute, blind, naked, 

 and shapeless. Yet even in this state they are al- 

 ways found adhering to the teats of the mother, 

 shrouded in her pouch. There they remain until 

 they have attained the size of a mouse, which is 

 not until the fiftieth day, at which period their eyes 

 are opened, and their bodies are covered with hair. 

 They now venture occasionally from their hiding- 

 place, returning to it on the least appearance of 

 danger ; nor is it until they have attained to a con- 

 siderable size that they finally quit their anxious 

 parent. The period of gestation is said to be twenty- 

 six days. 



64. — Merian's Opossum 

 (Didelphis dorsigera). Among the opossums, in 

 which a fold of the skin of the abdomen forms only 

 a rudimentary pouch, must be enumerated Merians 

 opossum. Though the other opossums with com- 

 plete marsupial pouches occasionally carry their 

 young on the back, with their tails twined round 

 that of the parent, still it is in these pouchless spe- 

 cies that this curious habit most usually prevails ; 

 hence the term dorsigera, which, though applied to 

 the present animal, might with equal propriety 

 be given to other species, as Didelphis brachyura, 

 cinerea, tricolor, and murina. 



Merian's opossum is a native of Surinam, and in 

 its habits it agrees with the rest of the genus. The 

 tail is slender, and longer than the head and body 

 taken together; at the base it is clothed with fur 

 resembling that of the body generally ; the naked 

 portion is of a pale brown tint. The fur of this 

 animal is short and lies close; on the upper parts of 

 the body it is greyish brown, the roots of the hairs 

 being paler. The under parts of the body are yel- 

 lowish white ; a deep brown spot encircles the eyes : 

 the forehead, top of the head, cheeks, outer side of 

 the limbs and feet, are yellowish white. Length, 

 from nose to root of tail about six inches ; length of 

 tail seven inches. A beautiful specimen of this 

 active little opossum, with its young clinging to it, 

 is preserved in the British Museum. 



65. — The Yapock Opossum 



(Cheironect.es palmatus). This interesting animal, 

 the yapock, is a native of Brazil, tenanting the 

 smaller streams and rivers, and it appears to extend 

 from the confines of that empire to the shores of 

 the Gulf of Honduras. Button's specimen was 

 procured in Cayenne. He terms it '■'■Petite Loutre 

 de la Guyene."' It is also called "Demerara otter." 



The yapock measures from ten to fourteen inches 

 long in the head and body, the tail being rather 

 more. The limbs are short, and the contour of the 

 body elongated. The ears are moderate, the nose 

 pointed ; the fur of the body close, short, somewhat 

 crisped and glossy ; the tail, excepting at the base, 

 is seal}'', the scales being spirally arranged and in 

 terspersed with fine, short, bristly hairs. The fore- 

 feet are divided into five long and slender toes, 

 armed with small weak claws, the innermost or 

 thumb excepted, which has a flat nail. It is not 

 opposable, though placed rather behind the general 

 line of the other toes. On the outside of the wrist 

 there is an elongated tubercle (the pisiform bone 

 developed) resembling a sixth finger, the use of 

 which is not apparent. The hind feet, which are 

 broad, are each divided into five toes, tied together 

 by ample webs ; the claws are small ; the inner toe 

 has a flat nail. This curious animal is furnished 

 with cheek-pouches of great size, which extend far 

 back along the sides of the mouth, and this circum- 

 stance, as Mr. Ogilby remarks, " hitherto unob- 

 served by zoologists, throws considerable light upon 

 the habits of this rare animal, which thus appears, 

 like the ornithorhynchus, to feed upon fresh-water 

 crustacea, the larvae of insects, the spawn of fishes, 

 &c, which it probably stows away in its capacious 

 cheek-pouches." Small fishes are doubtless among 

 its prey. 



The yapock, unlike the opossums, is incapable of 

 climbing : it is an aquatic animal, like the otter, 

 and lives in holes along the banks of the rivers which 

 it. frequents, and in which it seeks its food. It is 

 said to take its young early to the water. Two spe- 

 cimens in the possession of the celebrated naturalist 

 M. Natterer, were caught near water not far distant 

 from Rio Janeiro, and a third was captured alive 

 near Para, in a basket similar to those used in this 

 country for catching eels. It had made its way 

 through the funnel-shaped entrance, under water, 

 and could not return. 



The dentition of the yapock differs in some points 

 from that of the opossums : trie incisor and canine 

 teeth are the same in both, but the molars are only 

 five on each side, two false and three true, both in 



