“The palm of the hand and the five fingers which it supports are represented by the ribs of the wing and by po, which is the thumb. This is the shortest of the five fingers, as with man. It forms no part of the framework of the wing, but is free and is furnished with a hooked nail which the animal uses to cling by and also in walking. Finally, this thumb has two phalanges, as in the human thumb, and at the base is a small bone which in man forms a part of the palm of the hand. So much for the thumb.
“Now let us look at those four long bones that start from the wrist (ca) and spread out through the greater part of the wing. Together with the similar but shorter bone of the thumb they represent the series of five bones composing the framework of the human palm. Next come the fingers with their phalanges (ph). In short, except for a few slight differences, the bat’s wing reproduces, piece by piece, the structure of the human arm.”
“Yes,” Jules admitted, “it’s all there, even to the small bones of the wrist and fingers. Is it possible that a poor bat can pattern after us so closely? The horrid creature copies our arms to make itself wings.” [[40]]
“Your pride need not suffer from this close resemblance, which you will find in different degrees in a multitude of other animals, especially among the mammals, our next of kin in bodily structure. In the formation of his body man enjoys no monopoly; the dog, the cat, the donkey, the ox—each and all of them—share with us a common stock of organs, modified in details and suited to the kind of life of each species. We recognize in the bat’s wings the fundamental plan of our arms; we see it also no less plainly in the fore legs of the cat, the dog, and many other animals, and we can trace a rude resemblance to our hand even in the donkey’s homely hoof. I tell you these things, my children, not to lessen in your eyes the undeniable superiority of man, but to inspire in you a fellow feeling for animals that are formed like us, suffer as we do, and are far too often the victims of our stupid cruelty. Whoever needlessly causes an animal to suffer commits a barbarous act, an inhuman act, inasmuch as he inflicts torture on flesh like our own; he brutally misuses a body having the same mechanism as our own and the same power of suffering. As to our superiority, it is established preëminently by an exceptional characteristic that places us above all comparison even with creatures that in their physical structure most closely resemble us. This characteristic is reason, the torch that lights us in our search for truth; it is the human soul, which alone knows itself and enjoys the sublime privilege of knowing its divine Author. [[41]]
“In bats four of the five bones similar to those of our palm are greatly elongated, as are also the corresponding fingers, and they together constitute the four ribs on which is stretched the membrane of the wing, just as silk is stretched on the ribs of an umbrella. Thus it is at the sacrifice of what might have been a hand that the wing is formed. Therefore the scientists call all mammals of like structure with the bat ‘chiropters,’ meaning hand-winged creatures, from two Greek words signifying hand and wing.
“Of the five fingers one only, the thumb, is left free in the bat, and it is very small. It is furnished, as I said before, with a nail or claw. The four others, destitute of nails, are lengthened to serve as supports to the membrane of the wing. This membrane is a fold of the skin which starts from the shoulder, stretches between the four long fingers of the hand, and then attaches itself to the hind leg, the toes of which are all furnished with hooked nails or claws and do not depart from the ordinary shape of such members. By virtue of the free thumb already described the wings are able to serve as feet in walking, when these members are folded close to the animal’s sides. The bat grips the ground by thrusting in first the right claw and then the left, and pushes itself forward with its hind feet in laborious and awkward leaps. Thus it gets over the ground at what might be called a fast pace, but is soon tired out with the exertion; hence it does not walk except when sure it will not be molested or when it is compelled [[42]]to do so by its position on a level surface where it cannot launch itself into the air. Then as soon as possible it gains an elevated point, from which it flies off. For in order to unfold the hampering membranes that serve as wings and to throw itself into the air, the bat needs considerable free space, which it cannot get except by hurling itself from a height. Consequently, in the caves inhabited by bats they never fail to secure an unimpeded drop. With the hooked talons of a hind foot they cling to the roof, head downward. That is the way they rest, the way they sleep. At the slightest alarm the claw lets go, the wings spread, and the animal is off.”
“What a queer way to sleep,” Emile exclaimed, “hanging from the roof by one foot, head downward! And do they stay that way long without getting tired?”
“If necessary, a good half of the year.”
When he went to bed that night Emile thought again of the bat’s way of sleeping; but he preferred his own. [[43]]