Edward Tyson dissected and described the female opossum with care; in the individual which served him for subject, the head was six inches, the body thirteen, and the tail twelve in length: the fore legs were six inches, and the hind legs four inches and a half in height: the body was fifteen or sixteen inches in circumference; the tail three inches round in the beginning, and only one inch towards the extremities; the head three inches betwixt the two ears, decreasing gradually to the nose; and was more like that of a pig than a fox; the sockets of the eyes are much inclined in the direction from the ears to the nose; the ears are rounded, and about an inch and a half long; the mouth was two inches and a half wide from one of the corners of the lip to the extremity of the snout; the tongue narrow, three inches long, and rough; his fore feet had five toes armed with crooked claws, but in the hind feet he had only four toes with claws, and the fifth toe, or thumb, was separated from the others, was placed lower, and had no claws. All his claws were without hair, and covered with a skin of a reddish colour, and very near an inch in length; his hind and fore paws were large, and he had fleshy callosities under all the toes. The tail was covered with hair for two or three inches from the beginning, and the rest of it with a smooth scaly skin to the end. These scales were whitish, almost hexagonal, and placed regularly, so that they did not encroach upon each other, but were divided by a skin browner than the scales. The ears were without hair, thin and membranous like the wings of a bat, and very open. The upper jaw longer than the under; the nostrils large, the eyes small, black, and lively; the neck short, the breast wide, and the whiskers like those of a cat: the hairs of the forehead whiter and shorter than those of the body; his colour a yellowish grey, intermixed with black on the back and sides, more brown on the belly, and still deeper on the legs. Under the belly of the female ([fig. 131]) is a skin two or three inches long, which forms a kind of pouch by a double fold thinly covered with hair on the inside, and which pouch contains the teats. The young enter into this pouch to suck, and soon acquire the habit of hiding themselves in it, so that they retire thither whenever they are frightened. This pouch opens and shuts according to the will of the animal; which it effects by several muscles and two bones, which are peculiar to the opossum; these two bones are about two inches in length, placed by the os pubis, they decrease gradually from the basis to the extremities, and support the muscles which open the pouch; the antagonists of these muscles serve to shut it so exactly, that in the living animal the opening cannot be seen, without forcibly dilating it with the fingers. The inside of this pouch is full of kernels, which contain a yellow substance, the smell of which is so offensive, that it infects the whole body of the animal; yet when this matter is dried, it not only loses its disagreeable smell, but acquires a perfume which may be compared to that of musk. This pouch is not, as Marcgrave and Piso have falsely asserted, the place in which the young are conceived; the female opossum has an internal womb, different indeed from that of other animals, but in which the young are conceived, and remain till they are brought forth. Tyson says, that in this animal there are two wombs, two vaginas, and four ovariums. M. Daubenton does not agree with Tyson in these particulars; but by his description, it is at least certain, that in the organs of generation of the opossums, there are several parts double which are single in other animals. The glans penis of the male, and the glans clitoridis in the female, which are forked, and seem double. The vagina, which is single at the entrance, is afterwards divided into two channels; this conformation is very singular, and differs from that of all other quadrupeds.
The opossum belongs to the south parts of the new world, but he does not, like the armadillo, seem confined to the hottest climates, for he is found not only in Brasil, Guiana, and Mexico, but also in Florida, Virginia, and other temperate regions of this continent. They are very common in these countries, as they bring forth often, and most authors say four or five, others six or seven, at a time. Marcgrave affirms, that he has seen six young ones alive in the pouch of the female; they were about two inches in length, were very nimble, and went in and out of the pouch many times in a day. They are very small when just brought forth: some travellers say they are not bigger than flies when they go out of the womb into the pouch, and attach themselves to the teats. This fact is not so much exaggerated as might be imagined, for we have seen in an animal, whose species is somewhat like that of the opossum, young ones sticking to the teats not bigger than beans; and it is not improbable, that, in these animals, the womb is only the place of conception and first formation of the fœtus, whose unfolding is completed in the pouch. No one has observed the time of their gestation, which we think is shorter than in any other quadruped; and as this early exclusion of the fœtus is a singularity in nature, we wish those who have an opportunity of observing the opossums in their native country would contrive to discover how long the females go with young, and how long the young remain attached to the teats. This observation is curious in itself, and may become useful, in pointing out some means of preserving the lives of children born before their natural period.
That the young opossums stick to the teats of the mother till they have acquired strength, and a sufficient growth to move with ease, is a fact not to be doubted; nor is it peculiar to this species only, since we have seen it in that of the marmose. The female marmose has not, like the opossum, a bag under the belly; it is not, therefore, in consequence of the assistance which the young receive from the pouch that they stick so long to the teats, and increase in that immoveable situation. I make this observation to prevent the pouch being considered as a second womb, or at least an asylum necessary to the young before they are unfolded. Some authors pretend that they stick to the teats for several weeks, others say that they remain in the pouch only the first month after they came out of the womb. The pouch may be opened, the young counted, and even felt, without disturbing them, for they do not leave the teats, which they hold with their mouths, before they are strong enough to walk; then they fall into the bag, and afterwards go out to seek for their subsistence; they often go in again to sleep, to suck, and to hide themselves when terrified; in cases of danger the mother flies, and carries the whole of her young with her. Her belly does not seem to have any increased bigness when she is breeding, for in the time of the true gestation it is scarcely perceivable that she is with young.
From inspecting the form of the feet it is easy to perceive that he walks and runs aukwardly; it is said a man can overtake him without hastening his steps. He climbs up trees with great facility, hides himself in the leaves to catch birds, or hangs by the tail, the extremity of which is so muscular and flexible that he can clasp with it any thing he seizes upon. He sometimes remains a long while in this situation, his body suspended, with his head hanging downward, waiting for his prey. At other times he jumps from one tree to another, as the monkeys, with like muscular flexible tails, which he resembles also in the conformation of his feet. Though carnivorous, and even greedy of blood, which he sucks with avidity, he feeds also upon reptiles, insects, sugar-canes, potatoes, roots, and even leaves and bark of trees. He may easily be rendered a domestic animal, for he is neither wild nor ferocious; but he creates disgust by his smell, which is more offensive than that of the fox; his figure is also forbidding, for his ears are like those of an ounce, his tail resembles that of a serpent, his mouth is cleft to the very eyes, his body appears always dirty, because his hair is neither smooth nor curled, and seems as if covered with dirt. His bad smell resides in the skin, for his flesh is eatable. The savages hunt this animal by preference, and feed on his flesh heartily.
SUPPLEMENT.
M. de la BORDE has sent me an account of three opossums, which he kept in a cask at Cayenne; in most particulars it agrees with the description already given; he says they are very easily tamed, and feed upon fish, flesh, bread, &c. that those he had possessed no disagreeable smell, but that there are two species, the one which has so strong an odour as to be called stinking by the inhabitants, and that their flesh is not good to eat.
M. de Vosmaër, to his description of the flying squirrel, has added a note, in which he says, “the coes-coes is the bosch of the East Indies, the philandre of Seba, and the didelphiè of Linnæus. M. de Buffon has confined this animal to the new world, and positively denies its existence in the East Indies; but I can assure that learned naturalist that Valentin and Seba said no more than the truth, in affirming they were common to both Asia and America, for I have had a male and female sent me from the East Indies, and Dr. Schlosser, at Amsterdam received one of the same species from Amboyna. The principal difference between those of the East and West Indies is in the colour of the hair, the male of the former being of a yellowish white, and the female a little darker, with a brown line on the back, and their ears are less than those of the latter. The heads also of the West India species are much shorter than those of the East.” I have not the smallest reason to doubt M. Vosmaër’s receiving two animals from the East Indies, under the name of coes-coes, but am of opinion the differences which he points out are sufficient to induce us not to consider them the same species as the opossums. I, however, confess the justice of his observation upon my making the three philandres of Seba the same animal, when, in fact, the third is a different species, and found in the Philippine islands, and possibly in many parts of the East Indies, where it is called coes-coes, or cous-cous. Christopher Barchewitz gives a description of this animal found in the island of Lethy, and from the similarity it plainly appears, that the East India cuscus is of the same genus as the American opossum; but that is no proof of their being of the same species; and I am still of opinion, that the animals of one continent will not be found in the other, unless they have been transported thither. I do not mean to deny the possibility of the same climates in the two continents producing some animals of exactly the same species, provided other circumstances were the same; I am not, however, treating here of possibilities, but of general facts, of which we have given many instances in our enumeration of animals peculiar to the two continents; and, upon the whole, I am inclined to consider the coes-coes of the East Indies as an animal whose species approaches very near to that of the opossums of America, but that they have similar differences, to those which are observable between the jaguar and leopards, which of all animals peculiar to the southern climates of the two continents, without being the same species, come the nearest to each other.