In the limbs there are certain points of considerable interest and importance. If a Bear and a Lion be watched while walking, a great difference will be observed in their gait: the Bear’s movements are far clumsier and less springy than those of the Lion. A little further observation will show that this is due, chiefly, to the manner in which their feet are set on the limbs, for it will be seen that the Bear keeps the sole of his foot flat on the ground, and, as his foot is very large, he has something of the awkward, sprawling movement of a man walking in shoes too big for him. The Lion, on the other hand, has his wrist and his heel lifted well above the ground, and so walks, not on the sole of his foot, but on his toes, the under surfaces of which are furnished with beautifully soft leathery pads, so as to ensure a soft, silent footstep. Then what looks like the knee of a Lion, Cat, or Dog is really his _wrist_. and what looks like a backward turned knee in his hind leg is his heel, the true elbow and knee being almost hidden by the skin. The reason of this arrangement is seen by looking at the skeletons of the two animals. In the Bear the _metacarpals_ and _metatarsals_, or five long bones extending between the wrist and the ankle respectively, and the joints of the toes, are kept in a horizontal position, as in ourselves; in the Lion, on the contrary, the metacarpals and metatarsals are lifted almost into a vertical position, the walking surface being now afforded by the under surface of the toe-bones, or phalanges. By reason of this the Lion gets an extra lever in his leg, in addition to the two levers which the Bear possesses, namely, those afforded by the bones of the arm and fore-arm and of the thigh and leg respectively; and consequently his springiness is greatly increased. An animal which walks like the Bear, on the sole of its foot, is said to be _plantigrade_: one which walks on its fingers, like the Lion, Cat, or Dog, is called _digitigrade_. As in all animals in which the fore limbs are used for support, and not for prehension, the collar-bone, or clavicle, is either wholly absent or quite rudimentary, and the fore limb has therefore no bony connection with the trunk, but is attached simply by muscles and ligaments. The Carnivores, in leaping or running, often come down with their whole weight upon the fore legs, and if a large bony clavicle, like that of a Monkey or Bat, were present, it would infallibly be broken.