2. The field-spiders first of all deposit their ova in a web, of which one half is attached to themselves, and the other external, they incubate upon this, and produce their young alive. The phalangia deposit their ova in a thick basket which they weave, upon this they incubate. The smooth kinds produce a small number, the phalangia a great many. When they are grown, they surround their parent in a circle, kill and throw her out. They often seize the male in the same way if they can catch him, for he assists the female in incubation. Sometimes there are as many as three hundred round a single phalangium. The little spiders become full-grown in about four weeks. CHAPTER XXIII. 1. Locusts copulate in the same manner as all other insects, the smaller mounting upon the larger, for the male is the smaller. They oviposit by fixing the organ which is attached to their tail (the ovipositor) in the ground. The males do not possess this organ. Many of them deposit their ova in one spot, so as to make it appear like a honey-comb. As soon as they have deposited their ova, egg-like maggots are formed, which are covered with a thin coating of earth like a membrane, and in this they are matured. 2. The young are so soft as to collapse if they are only touched. They are not produced on the surface, but a little below the surface of the soil; and as soon as they are matured, they escape from the coat of soil in which they are enclosed as small black locusts. Their skin is subsequently ruptured, and they then attain their full size. They produce their young at the end of summer, and then die. 3. For as soon as they have deposited their ova, small worms make their appearance on their necks, the males also perish at the same time: they come out of the earth in the spring. Locusts never shew themselves in mountainous countries, nor in poor land, but in plains, and broken soil, for they deposit their ova in fissures. The ova remain in the soil during the winter, and in the summer the locusts are produced from the germs of the preceding year. 4. The young of the attelabi are produced in the same manner, and the parents die after having deposited their ova. Their ova are destroyed by the rains of the autumn, if the weather is wet; but if that season is dry, many attelabi are produced, because they are not equally destroyed; for their destruction appears to be irregular, and to take place by accident. CHAPTER XXIV. 1. There are two kinds of grasshoppers: some are small. These are the first to appear, the last to perish. Others, which chirp, are large: these appear last, and disappear first. There is another difference between the small and large kind. Those which chirp have a division in the middle of the body: those which do not chirp have none. The large ones, which chirp, are called achetæ; the small are called tettigonia. Such of these as are divided, sing a little.