These were not, however, ants' eggs. They were the eggs of aphides. The young which were soon to be hatched were to give to the provident ants a reward for the attentions they had lavished upon them. How wonderful are the life and the habits of the plant-lice, and their relations to ants! But we should be led on too far, if we were to pursue these attractive details.

We pass on now to the history of another family—namely, the Gallinsecta, as Réaumur calls them, or Cocci. They pass the greatest part of their lives—that is to say, many months—entirely motionless, sticking to the stalks or branches of shrubs; remaining thus as devoid of movement as the plant to which they are attached. One would say that they were part and parcel of it. Their form is so simple, that nothing in their exterior would make one guess them to be insects. The larger they become the less they resemble living things. When the coccus is in a state for multiplying its species, when it is engaged in laying its thousands of eggs, it resembles only an excrescence of the tree.

The Gallinsecta are found on the elm, the oak, the lime, the alder, the holly, the orange-tree, and the oleander. Some of the species are remarkable for the beautiful red colouring matter which they furnish. Such are the Coccus cacti, the Chermes variegatus, or Oak Tree Cochineal, and the Coccus polonicus.

The Common Cochineal, Coccus cacti, is found in Mexico, on the Nopal, or prickly pear (Opuntia), particularly on the Opuntia vulgaris, the Opuntia coccifera, and the Opuntia una, plants which belong to the family of the Cactaceæ.

These insects are rather remarkable, in that the male and female are so unlike, that one would take them for animals of different genera.

The male presents an elongated, depressed body, of a dark-brown red. Its head small, furnished with two long feathery antennæ, has only a rudimentary beak. The abdomen is terminated by two fine hairs, longer than its body. The wings, perfectly transparent, reach beyond the extremity of its abdomen, and cross each other horizontally over its back. It is lively and active. The female presents quite a different appearance. It is in the first place twice as large as the male ([Fig. 92]), convex above, flat below. It resembles a larva, and has no wings. Its body is formed of a dozen segments, covered with a glaucous dust. The beak is very fully developed, and the two hairs or bristles on the abdomen are much shorter than in the male.

Fig. 92.
Cochineal insects, (Coccus cacti)
male and female.

The weight of the body, combined with the shortness of the legs, prevents these creatures from being active. The legs only serve, in fact, for clinging to the vegetable from which they draw their nourishment. The circumstances attending the birth of the cochineal insect are very curious. The larvæ are born in the dried-up body of their dead mother, the skeleton of their mother serving them as a cradle. This happens thus:—The eggs are attached to the lower part of the mother's body. When the abdomen of the mother is empty, its lower side draws up towards the upper side, and the two together form a pretty large cavity. When the mother dies, which is not long in happening, her abdomen dries up, her skin becomes horny, and forms a sort of shell. It is in this membranous cradle that the larvæ of the cochineal insect are born. The cochineal insect in its wild state lives in the woods. But it can without difficulty be reared artificially.