Then you would notice that this loose skin is fastened along the inner side of each leg, so that the limbs are connected by membrane just like the toes of a duck's foot. And you would also see that when the legs are stretched out at right angles to the body, this membrane must be stretched out with them.
Now when a colugo wishes to take a long leap, it springs from the tree on which it is resting, spreads out its limbs, and skims through the air just as an oyster-shell does if you throw it sideways from the hand. The air buoys it up, you see, and enables it to travel ten times as far as it could without this loose skin. But of course this is not flight. The animal does not beat the air with the membrane between the legs, as bats and birds do with their wings. It cannot alter its course in the air; and it is always obliged to alight at a lower level than that from which it sprang.
The colugo is about as big as a good-sized cat, and its fur is olive or brown in color, mottled with whitish blotches and spots. When it clings closely to the trunk of a tree, and remains perfectly motionless, it may easily be overlooked, for it looks just like a patch of bark covered with lichens and mosses. It is said to sleep suspended from a branch with its head downward, like the bats; and whether this is the case or not, its tail is certainly prehensile, like that of a spider-monkey. And strangest of all, perhaps, is the fact that, although it belongs to the group of the insect-eaters, it feeds upon leaves.
In European countries, where it is common, one can scarcely walk through the meadows on a summer's evening without seeing this curious animal as it moves clumsily about in search of prey. There everybody is familiar with its spiky coat, which affords such an excellent protection against almost all its enemies.
But it is not everybody who knows how the animal raises and lowers its spines. It has them perfectly under control; we all know that. If you pick a hedgehog up it raises its spines at once, even if it does not roll itself up into a ball and so cause them to project straight out from its body in all directions. But if you keep the creature as a pet, and treat it kindly, it will very soon allow you to handle it freely without raising its spines at all.