But the most extraordinary changes and series of different individuals are found among the so-called white ants, which are really not ants at all, but among the most destructive of all known insects. The first white travelers in Africa reported the discovery of gigantic ant hills, some of which were twelve feet in height (Fig. 190) and one hundred feet in circumference. Equally large mounds have been found in Australia, large areas of country being dotted with these striking landmarks, among the most remarkable of all animal structures. These mounds are often as hard as rock, and hunters have sometimes escaped from the charges of wild animals by climbing upon them. [Illustration: FIG. 189.--Aphis lion, larva and eggs.] They are the work of the so-called white ants. A section made through one of them, as seen in the illustration, shows the singular home of a remarkable community. There are really four kinds of "ants" here, all representing a different phase in the growth of the insect, and all performing a certain work. They are the female, the male, the worker, and the soldier; and there is a winged king. In their lives these insects have many features which resemble those of man. They have a king and queen, which at first have wings; later they lose their wings and the queen grows until she is thousands of times larger than the workers, and is kept in a special chamber in the center of the pile. Here she is attended by the workers, small ants, who carry out the eggs which are laid by millions and placed in nurseries or small cemented cells, designed for the purpose. Sometimes the queen lays as many as eight thousand eggs a day. An army of workers carries them off, builds new nurseries, and adds to the heap. If an enemy appears, the soldiers rush out. These have large heads and enormous jaws, and are well fitted by nature for the work they have to perform. [Illustration: FIG. 190.--Hills of the white ant.] The cunning and intelligence of white ants are well displayed in their attacks upon houses. Having decided to enter a house, they begin to tunnel some distance away, and finally reach the corner post or some timber that enters the ground. With remarkable speed the workers enter this, hollowing it out, until it is nothing but a shell. They eat to the very surface, leaving only a faint ghost of a partition, and what appears to be a solid block is really so thin that a finger can be thrust through it. So clever are these little ant miners that they have been known to come up through the floor directly beneath the leg of a chair, and burrow and eat up through it, so completely devastating it that when the owner moved it the small hole in the floor appeared and the chair fell in pieces.