Rhynchites
A genus of Weevils, noteworthy for the harm done by several of the species to trees. Some of them have the habit of rolling part of a leaf, or one or more leaves, into a cone, to supply protection and food to the larvae. The cones hang in a withered state by the half-cut stalks or midribs of the leaves. Others gnaw partly through young shoots, or young fruit, and lay one or more eggs in each, and the larvae feed in the withered branch or fruit. By the time the larva is full-fed, the part of the plant containing it has usually fallen off, and the larva crawls into the earth, there becomes a pupa, and, finally, the beetle emerges, generally in the following spring. The beetles are harmful also by gnawing the young leaves and branches of most kinds of trees, including fruit-trees, for their own food. They are all small, usually being from 1/8in. to 1/4in. long. The general outline is broadly pear-shaped, the wing-cases being rather square in front, and broader than the thorax. The head bears a rather long, decurved beak, on the middle of which are the straight, clubbed antennae. The beetles are all shining dark blue, green, brown, or coppery-red in colour. Reference has already been made to these insects as injurious to Pear-trees, Plum-trees, &c. The following are the most hurtful species:
R. Alliariae is much like R. conicus in size and colour, but the thorax is finely pitted, and has a smooth dorsal line, and the elytra are not decidedly wider behind the middle. The larvae live in the stalks and midribs of the leaves of many fruit-trees, e.g., Apple, &c.
R. Bacchus is 1/4in. to 1/3in. long, purple-red, with a golden-coppery gleam on the wing-cases and on the back of the neck; beak, legs, and antennae are blue-black; wing-cases deeply punctured, and transversely wrinkled. This species prefers Apple and Pear trees, but is not restricted to them. The larvae live in the still unripe fruits, which are hindered and interfered with in their growth.
R. betuleti is about 1/3in. long, or more, entirely blue or shining green, or a combination of these, and hairless; wing-cases closely punctate, irregularly striate, not wrinkled. The beetles live on many kinds of trees, but prefer, among those of gardens, Pear-trees and Vines. The females make conical habitations for the larvae out of one or several leaves rolled together, and caused to wither by their stalks being partly gnawed through, as stated above. R. conicus is from 1/8in. to 1/6in. long; colour deep blue, sometimes with a greenish tinge; beak and limbs black; thorax coarsely pitted; wing-cases deeply punctate-striate, broadest behind the middle. In May and June, the females lay eggs in the young shoots of Apples, Pears, Plums, Cherries, and other fruit-trees, and then gnaw the branches partly through below the situation of the eggs. The branches fade and hang down, and in this state form the proper food of the larvae, which feed in the pith. R. cupreus is about 1/5in. or 1/4in. long, and is coppery or bronze-coloured, with a thin coat of greyish hairs; the beak and limbs are black; the thorax is closely punctured; the elytra are deeply punctate-striate, with the interspaces transversely wrinkled. The beetles live on all kinds of fruit-trees in early summer, and do considerable harm by gnawing the young shoots and buds; but they prefer Cherries and Plums. The females seek out the young fruits, and deposit an egg in a hole bored in each, after the stalk is gnawed half through, so that, after a time, the fruits fall to the earth. The larvae feed in the fruits till ready to enter the soil, there to become pupae. A beetle of this genus, R. bicolor, injures Roses in the United States. Remedies. These consist of the capture of the beetles by shaking the trees over trays tarred inside, and the removal of the conspicuously injured leaves, young branches, or fruits, to be burned as soon as convenient. Fortunately, the evil can be checked, in most cases, without serious labour.