Next to Zygæna comes Procris, the species of which fly during the day in damp fields. We will mention particularly the Procris statices ([Fig. 177]), which is plentiful enough where it occurs between the middle of June and the middle of July, on the sides of hills. Its fore wings, antennæ, and the whole of its body, are of a blue green above. The same wings are of the same colour below, and the surfaces of the lower ones are of an ashy brown.
Fig. 177.—The Forester (Procris [Ino] statices)
The Sphinges, that is, those species that form the family of the Sphingidæ, have received this general name from the attitude which their caterpillars often assume. Raising the fore part of the body, which attitude resembles the Sphinx of mythology, they keep for a very long time this state of immobility. They fly very rapidly and briskly, and only make their appearance for the most part after sunset. The caterpillars, which in this group are without hair, and have almost always a horn on the eleventh segment of the body, metamorphose themselves in the earth, without forming hard cocoons. The chrysalis are sometimes enveloped in a very slight shell, or cocoon, which when it exists is formed of particles of earth or of vegetable débris bound together by threads. This family comprises species generally remarkable for their size and beauty.
The genus Macroglossa contains some species which fly rapidly and for a long time together during the day. We will mention particularly the Humming-bird Sphinx (Macroglossa stellatarum). This moth ([Fig. 178]) has attracted the attention of all who have ever spent much time in a flower garden. In Burgundy the children call it bird-fly. In passing from one flower to another it has brisk and rapid movements, but it remains suspended in the air before each; it does not alight upon any, it is always flying, thrusting its long trunk the while into the corollæ of flowers, counterbalancing the action of its weight by the continuous vibration of its wings.
We will describe in a few words this robust inhabitant of the air, this charming bird-fly. The Macroglossa stellatarum shows itself during the whole of the fine season, and till the middle of autumn, in our climate. It often penetrates in the middle of the day into our houses, and knocking itself against the window-panes, falls an easy prey to children. Its front wings are of an ashy brown, of changing hues above, with three black, transverse, undulating lines. The lower, shorter than the others, are of a rusty-yellow colour. All the wings are yellowish below near the body, ferruginous in the middle, and of a dark brown at their extremities.
Fig. 178.—Humming-bird Hawk-Moth (Macroglossa stellatarum).