Moulting.—Probably everybody who lives in the country has seen a snake's skin without any snake in it. It is often very perfect. When the outside skin or cuticle of a snake or a toad gets old and dry or too tight for it, a new covering grows underneath, and the old one is shed. This is a very interesting performance, but the toad usually sheds it in a retired place, so the process is not often seen. Those who have seen it say that a long crack or tear appears along the back and in front. The toad keeps moving and wriggling to loosen the old cuticle. This peels the cuticle off the sides. Now, to get it off the legs and feet, the toad puts its leg under its arm, or front leg, and in that way pulls off the old skin as if it were a stocking. But when the front legs are to be stripped the mouth is used as is sometimes done by people in pulling off their gloves. Do you think it uses its teeth for this purpose? You might look in a toad's mouth sometime, and then you would know.
Fig. 120. Snakes frequently swallow toads hind legs foremost, as shown in the picture. This is especially true of the garter snake, which is a great enemy of the toad.
It is said that when the skin is finally pulled off the toad swallows it. This is true in some cases; at least it is worth while keeping watch for. It is certain that the toad sometimes swallows the cast skin; it is also certain that in some cases the cast skin is not swallowed. After a toad has shed his old skin, he looks a great deal brighter and cleaner than before, as if he had just got a new suit of clothes. If you see one with a particularly bright skin, you will now know what it means.
Hibernation.—The toad is a cold-blooded animal. This means that the temperature of its blood is nearly like that of the surrounding air. Men, horses, cows, dogs, are said to be warm-blooded, for their blood is warm and of about the some temperature whether the surrounding air is cold or hot.
When the air is too cool, the toad becomes stupid and inactive. In September or October a few toads may be seen on warm days or evenings, but the number seen becomes smaller and smaller; and finally, as the cold November weather comes on, none are seen. Where are they? The toad seems to know that winter is coming, that the insects and worms will disappear, so that no food can be found. It must go into a kind of death-like sleep, in which it hardly moves or breathes. This winter sleep or hibernation must be passed in some safe and protected place. If the toad were to freeze and thaw with every change in the weather it would not wake up in the spring.
Fig. 121. Toad in the winter sleep. (Natural size).
The wonderful foresight which instinct gives it, makes the toad select some comparatively soft earth in a protected place where it can bury itself. The earth chosen is moist, but not wet. If it were dry the toad would dry up before spring. It is not uncommon for farmers and gardeners to plough them up late in the fall or early in the spring. Also in digging cellars at about these times they are found occasionally.
In burying itself the toad digs with its hind legs and body, and pushes itself backward into the hole with the front legs. The earth caves in as the animal backs into the ground, so that no sign is left on the outside. Once in far enough to escape the freezing and thawing of winter, the toad moves around till there is a little chamber slightly larger than its body; then it draws its legs up close, shuts its eyes, puts its head down between or on its hands, and goes to sleep and sleeps for five months or more.