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slender and almost cylindrical, of a deep chestnut-brown color, rendered gray, however, by the numerous short yellowish hairs with which it is covered; the thorax is of moderate length, not much narrowed before, convex above, with very long and sharp-pointed hinder angles, and in certain lights has a brassy hue; the wing-covers are finely punctured, and have very slender impressed longitudinal lines upon them; the claws are not toothed beneath. This beetle usually measures from four to five tenths of an inch in length; but the females frequently greatly exceed these dimensions, and, being much more robust, with a more convex thorax, were supposed by Mr. Say to belong to a different species, named by him brevicornis, the short-horned. The larvæ are not yet known to me; but I have strong reasons for thinking that they live in the ground upon the roots of the perennial grasses and other herbaceous plants.
Although above sixty different kinds of spring-beetles are now known to inhabit Massachusetts, I shall add to the foregoing a description of only one more species. This is the Elater (Agriotes) obesus of Say. It is a short and thick beetle, as the specific name implies; its real color is a dark brown, but it is covered with dirty yellowish gray hairs, which on the wing-covers are arranged in longitudinal stripes; the head and thorax are thickly punctured, and the wing-covers are punctured in rows.
Its length is about three tenths of an inch. This beetle closely resembles one of the kinds, which, in the grub state, is called the wire-worm in Europe, and possibly it may be the same. This circumstance should put us on our guard against its depredations. It is found in April, May, and June, among the roots of grass, on the under side of boards and rails on the ground, and sometimes also on fences.
The utility of a knowledge of the natural history of insects in the practical arts of life, was never more strikingly and triumphantly proved than by Linnæus himself, who, while giving to natural science its language and its laws, neglected no opportunity to point out its economical advantages.* On one occasion this great naturalist was consulted by the King of Sweden upon the cause of the decay and destruction of the ship-timber in the royal dock-yards, and, having traced it to the depredations of insects, and ascertained the history of the depredators, by directing the timber to be sunk under water during the season when these insects made their appearance in the winged state, and were busied in laying their eggs, he effectually secured it from future attacks.
* See the preface to Smith's " Introduction to Botany,” and Pulteney's “ View of the Writings of Linnæus," for several examples, one of which it may not be amiss to mention here. Linnæus was the first to point out the advantages to be derived from employing the Arundo arenaria, or beach-grass, in fixing the sands of the shore, and thereby preventing the encroachments of the sea. The Dutch have long availed themselves of his suggestion, and its utility has been tested to some extent in Massachusetts.
The name of these insects is Lymexylon navale, the naval timber-destroyer. They have since increased to an alarming extent in some of the dockyards of France, and in one of them, at least, have become very injurious, wholly in consequence of the neglect of seasonable advice given by a naval officer, who was also an entomologist, and pointed out the source of the injury, together with the remedy to be applied.
These destructive insects belong to a family called LYMEXYLIDE, which may be rendered timber-beetles. They cannot be far removed from the Buprestians and the spring-beetles in a natural arrangement. From the latter, however, the insects of this small group are distinguished by having the head broad before, narrowed behind, and not sunk into the thorax; they have not the breast-spine of the Elaters, and their legs are close together, and not separated from each other by a broad breast-bone as in the Buprestians; and the hip-joints are long, and not sunk into the breast. In the principal insects of this family the antennæ are short, and, from the third joint, flattened, widened, and saw-toothed on the inside; and the jawfeelers of the males have a singular fringed piece attached to them. The body is long, narrow, nearly cylindrical, and not so firm and hard as in the Elaters. The feet are five-jointed, long, and slender.
The larvæ of Lymexylon and Hylecætus are very odd-looking, long, and slender grubs. The head is small; the first ring is very much hunched; and on the top of the last ring there is a fleshy appendage, resembling a leaf in Lymexylon, and like a straight horn in Hylecætus. They have six short legs near the head. These grubs inhabit oak-trees, and make long cylindrical burrows in the solid wood. They are also found in some other kinds of trees.
Only a few native insects of this family are known to me, and these fortunately seem to be rare in New England. I shall describe only two of them. The first was obtained by beating the limbs of some forest-tree. It may be called Lymexylon sericeum, the silky timber-beetle. It is of a chestnut-brown color above, and covered with very short shining yellowish hairs, which give it a silky lustre. The head is bowed down beneath the fore part of the thorax; the eyes are very large, and almost meet above and below; the antennæ are brownish red, widened and compressed from the fourth to the last joint inclusive; the thorax is longer than wide, rounded before, convex above, and deeply indented on each side of the base; the wing-covers are convex, gradually taper behind, and do not cover the tip of the abdomen; the under side of the body, and the legs, are brownish red. Its length is from four to six tenths of an inch. This insect was unknown to Mr. Say, and does not seem to have been described before.
The generical name Hylecætus, given to some insects of this family, means a sleeper in the woods, or one who makes his bed in the forest. We have one hitherto undescribed species, which may be called Hylecætus Americanus, the American timber-beetle. Its head, thorax, abdomen, and legs are light brownish red; the wing-covers, except at the base where they are also red, and the breast, between the middle and hindmost legs, are black. The head is not bowed down under the fore part of the thorax; the eyes are small and black, and on the middle of the forehead there is one small reddish eyelet, a character unusual among beetles, very few of which have eyelets; the antennæ resemble those of Lymexylon sericeum, but are shorter; the thorax is nearly square, but wider than long; and on each wing-cover there are three slightly elevated longitudinal lines or ribs. This beetle is about four tenths of an inch long. It appears on the wing in July.
The foregoing beetles, though differing much in form and habits, possess one character in common; namely, their feet are five-jointed. Those that follow have four-jointed feet. In this great section of Coleopterous insects are arranged the Weevil tribe, the Capricorn beetles or long-horned borers, and various kinds of leaf-eating beetles, all of which are exceedingly injurious to vegetation.
So great is the extent of the Weevil tribe,* and so imperfectly known is the history of a large part of our native species, that I shall be obliged to confine myself to an account of a few only of the most remarkable weevils, and principally those that have become most known for their depredations. Mr. Köllar's excellent “ Treatise on Insects injurious to Gardeners, Foresters, and Farmers," contains an account of several kinds of weevils that are unknown in this country; and indeed but few resembling them have hitherto been discovered here. Should future observations lead to the detection in our gardens and orchards of any like those which in Europe attack the vine, the plum, the apple, the pear, and the leaves and stems of fruit-trees, the work of Mr. Köllar may be consulted with great advantage.
Weevils, in the winged state, are hard-shelled beetles, and are distinguished from other insects by having the fore part of the head prolonged into a broad muzzle or a longer and more slender snout, in the end of which the opening of the mouth and the small horny jaws are placed. The flies and moths produced from certain young insects, called weevils by mistake, do not possess these characters, and their larvæ or young differ essentially from those of the true weevils. The latter belong to a group called RHYNCHOPHORIDÆ, literally, snout-bearers. These beetles are mostly of small size. Their antennæ are
* See page 18.
usually knobbed at the end, and are situated on the muzzle or snout, on each side of which there is generally a short groove to receive the base of the antennæ when the latter are turned backwards. Their feelers are very small, and, in most kinds, are concealed within the mouth. The abdomen is often of an oval form, and wider than the thorax. The legs are short, not fitted for running or digging, and the soles of the feet are short and flattened. These beetles are often very hurtful to plants, by boring into the leaves, bark, buds, fruit, and seeds, and feeding upon the soft substance therein contained. They are diurnal insects, and love to come out of their retreats and enjoy the sunshine. Some of them fly well; but others have no wings, or only very short ones, under the wing-cases, and are therefore unable to fly. They walk slowly, and being of a timid nature, and without the means of defence, when alarmed they turn back their antennæ under the snout, fold up
their legs, and fall from the plants on which they live. They make use of their snouts not only in feeding, but in boring holes, into which they afterwards drop their eggs.
The young of these snout-beetles are mostly short fleshy grubs, of a whitish color, and without legs. The covering of their heads is a hard shell, and the rings of their bodies are very convex or hunched, by both of which characters they are easily distinguished from the maggots of fies. Their jaws are strong and horny, and with them they gnaw those parts of plants which serve for their food. It is in the grub state that weevils are most injurious to vegetation. Some of them bore into and spoil fruits, grain, and seeds; some attack the leaves and stems of plants, causing them to swell and become cankered; while others penetrate into the solid wood, interrupt the course of the sap, and occasion the branch above the seat of attack to wither and die. Most of these grubs are transformed within the vegetable substances upon which they have lived; some, however, when fully grown, go into the ground, where they are changed to pupæ, and afterwards to beetles.
In the spring of the year we often find, among seed-pease, many that have holes in them; and, if the pease have not been exposed to the light and air, we see a little insect peeping out