Ants are provided with antennæ, bent in the form of an elbow, with which they examine everything they meet, and which seem to assist them in the communication of their ideas. Two horny, very strong mandibles serve them at the same time as pincers, tweezers, scissors, pick-axe, fork, and sword. A thin short neck joins the head to the thorax, to which, in the case of the males and females, are attached four large veiny wings. The workers only have no wings. Of the three pairs of legs, the hind ones are the longest. Each pair is armed with a spur, and fringed with very short hairs, which serve the purpose of brushes. The abdomen, large, short, oval, or square, is always most voluminous in the females. There are three genera of ants which we shall mention. The _Myrmicæ_ have two knobs to the pedicle, by which the abdomen is attached to the thorax; the _Poneræ_ only one. In these two genera, the females and the neuters have a sting, and the larvæ do not spin a cocoon in which to change into pupa. Lastly, the _Formicæ_--ants properly so called--have but one knob on the pedicle of the abdomen, as in _Ponera_; their larvæ spin a silky cocoon. They have no sting, but they pour into the wounds made by their mandibles an acid liquor, the pungent smell of which is well known. This liquid is formic acid, a natural product, which the chemist now-a-days knows how to make artificially, by the action of dilute sulphuric acid on maize and other vegetable matters. Their whole body is impregnated with this acid, and has a strong sour smell. Some people like to chew ants, on account of their sourish taste. "They also make," says Charles de Geer, "creams for side-dishes, to which these ants give, they say, the taste of lemon-juice." We know, in the south of France, people who have eaten these _crèmes aux fourmis_! _Polyergus_ forms a sub-genus of _Formica_. [Illustration: Fig. 361.--Sections of an Ant's Nest.] In all these species, the workers, or neuters, have the charge of the building, provisioning, and rearing of the larvæ--in fact, all the care of the household, and the defence of the nest. Deprived of wings, they are bound to the soil, and condemned to work. As compensation, to them belong strength, authority, power: nothing is done but through them. "Born protectors of an immense family still in the cradle," says M. Victor Rendu, "by their vigilance, their tenderness, and their solicitude, without being mothers themselves, they share in the duties and joy of maternity. Alone, they decide on peace or war; alone, they take part in combats: head, heart, and arm of the republic, they ensure its prosperity, watch over its defence, found colonies, and in their works show themselves great and persevering artists."