Page:Popular Science Monthly Volume 8.djvu/162

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THE POPULAR SCIENCE MONTHLY.

the eyes, the long pointed nose, the feet and tail, are colored quite dark. The strong, round, slender tail is destitute of hair, but covered, like the beaver's, with scales. But the most peculiar feature of this animal is the mammary pocket, or marsupium, formed by a folding-in of the skin on the abdomen. Its character is marked by wonderful cunning and stupidity combined. The daytime it spends in slothful idleness, but prowls about nocturnally seeking for food. Walking or slowly ambling at an awkward gait, it proceeds from place to place, usually following the borders of streams and ponds, often wading where the water is shallow. But its limbs seem best adapted to climbing; the plantigrade, hand-like feet, with thumbs[1] opposable to the fingers, and the long, prehensile tail, strongly indicate scansorial habits and arboreal life. Among the trees it manifests astonishing agility, climbing or swinging from branch to branch with perfect safety, and may be seen hanging by one or more of its feet, or by its tail alone, while busily engaged gathering and eating the wild-grapes, or haw, or persimmon, of which it is peculiarly fond, or robbing birds'-nests of their eggs or young. A varied diet suits its omnivorous appetite, and it fares promiscuously on fruits, vegetables, eggs, insects, worms, reptiles, small quadrupeds, and birds, often stealing domestic fowls. It commonly hides among vines and branches, in hollow trees or logs, or in holes in the ground. In these places also its nests of grass and leaves are found. In autumn, the opossums become excessively fat, and are then prized for food in the Southern States, especially by the negroes, whose fondness for hunting them and eating their flesh has already exterminated them from many localities where they abounded plentifully before. Their flesh, when cooked, resembles roast-pig. The animal is usually sullen, stupid, and slow, but if attacked assumes a terribly fierce attitude, snarls, utters a kind of hiss and low growl, and will often bite ferociously, though at the first blow wall usually feign death, and no amount of torture will make it revive or show a sign of suffering, but when beaten and left for dead it will

  1. In the October "Miscellany" (p. 758) of this Journal, some of the facts concerning my contributions to the myology of the apes and man appeared incorrectly reported. Since the opossum's foot was wrongly referred to as being typical and unlike the hand of man, the mistake may be corrected here. The comparison of man's foot with the opossum's was unfortunate; the right idea was expressed, but a wrong illustration chosen. The fact is, the opossum is pedimanous, having an opposable thumb, as was stated in a paper presented at the same time with the above. It has a rather highly-differentiated foot, whereas the contrary was supposed.

    Few, if any, animals outside the groups of the quadrumana and the opossum family have the parts of their muscles so specialized that one toe can be used without moving all the others.

    Instead of "one communis muscle," there are several in every typical foot. My papers show that the so-called "proprius" muscles, such as the special extensors of the index, thumb, little finger, etc., which characterize the hands of man and some of the apes, are but parts differentiated off from one or another of the "communis" muscles, and are found as parts of those muscles in lower animals with more typical feet.