The great bat, or noctule,[87] has a spread of wing of twelve or fourteen inches, while its body is only three inches long. Its mouth can open with a wide gap like that of a swallow. When it catches a beetle, it has to hold it to its mouth by its thumb claw while it eats it, as a boy would eat a pear. To bring the thumb around to its mouth the bat must partly close the wing; as it does this it drops a foot or so; then it gives a stroke or two of its wings as it chews the bite it has taken, and rises again; then it takes another bite of beetle, and so on. All the time it is hunting it gives shrill squeaks or cries. Not only is the free thumb of the bat’s hand useful for holding food, but it is of great service in walking, as its method is to extend the arm, catch hold of the ground by the claw of one free thumb, and pull itself forward; then make the same motion with the other arm and thumb, the free feet following these movements. Thus it proceeds in a zigzag, moving first to one side and then to the other. Although this is such an awkward method of progress the bat can run rapidly. Bats are not great travellers; they haunt the same locality year after year. The mother bat has seldom more than one young one at a time, and this is born early in the spring, before the bats begin to fly abroad. The baby bat is smaller than a small bean, is blind and hairless. The mother bat folds up a part of her wing membrane into a cradle or nest for this tiny creature; she seems very fond of it, smooths and brushes it, and keeps it warm and clean. The little creature has from the first strong claws, and uses them to hold fast to its mother. For several weeks this little one clings to its mother, is fed by her milk, and when she goes out to hunt she carries it along and never lets it fall. Even after a young bat can fly and catch insects for itself, it keeps near its mother, and she watches over it, and timid as she is by nature, she will die in its defence. Bats are found in nearly all parts of the world, and may be divided according to their food into insect-eating and fruit-eating bats. The insect-eating bats belong generally to cold or mild climates, and the fruit-eaters to the tropics. The fruit-eating bats are much larger than the insect-eaters, and they are destructive and troublesome, while the common bats are useful.