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their prison, crawl through the passages the larvæ had gnawed, and come forth on the outside of the trees.
The largest of these beetles in the New England States, was first described by Linnæus under the name of Lucanus Capreolus,* signifying the young roe-buck; but here it is called the horn-bug. Its color is a deep mahogany-brown; the surface is smooth and polished; the upper jaws of the male are long, curved like a sickle, and furnished internally beyond the middle with a little tooth; those of the female are much shorter, and also toothed; the head of the male is broad and smooth, that of the other sex narrower and rough with punctures. The body of this beetle measures from one inch to one inch and a quarter, exclusive of the jaws. The time of its appearance is in July and the beginning of August. The grubs live in the trunks and roots of various kinds of trees, but particularly in those of old apple-trees, willows, and oaks. All the foregoing beetles have, by some naturalists, been gathered into a single tribe, called lamellicorn or leaf-horned beetles, on account of the leaf-like joints wherewith the end of their antennæ is
The beetles next to be described, have been brought together into one great tribe, named serricorn or saw-horned beetles, because the tips of the joints of their antennæ usually project more or less on the inside, somewhat like the teeth of a saw. The beetles belonging to the family BUPRESTIDÆ, or the Buprestians, have antennæ of this kind. The Buprestis of the ancients, as its name signifies in Greek, was a poisonous insect, which, being swallowed with grass by grazing cattle, produced a violent inflammation, and such a degree of swelling as to cause the cattle to burst. Linnæus, however, unfortunately applied this name to the insects of the above-mentioned family, none of which are poisonous to animals, and are rarely, if ever, found upon the grass. It is in allusion to the original signification of the word Buprestis, that popular English writers on natural history sometimes give the name of burncow to the harmless Buprestians; while the French, with greater propriety call them richards, on account of the rich and brilliant colors wherewith many of them are adorned. The Buprestians, then, according to the Linnæan application or rather misapplication of the name, are hard-shelled beetles, often brilliantly colored, of an elliptical or oblong oval form, obtuse before, tapering behind, and broader than thick, so that, when cut in two transversely, the section is oval. The head is sunk to the eyes in the fore part of the thorax; and the antennæ are rather short, and notched on one side like the teeth of a saw. The thorax is broadest behind, and usually fits very closely to the shoulders of the wing-covers. The legs are rather short, and the feet are formed for standing firmly, rather than for rapid motion; the soles being composed of four rather wide joints, covered with little spongy cushions beneath, and terminated by a fifth joint, which is armed with two claws. Most beetles, as already stated, have a little triangular piece, called the scutel, wedged between the bases of the wing-covers and the hinder part of the thorax, commonly of a triangular or semicircular form, and in the greater number of coleopterous insects quite conspicuous; in the Buprestians, however, the scutel is generally very small, and sometimes hardly perceptible. These beetles are frequently seen on the trunks and limbs of trees basking in the sun. They walk slowly, and, at the approach of danger, fold up their legs and antennæ and fall to the ground. Being furnished with ample wings, their flight is swift and attended with a whizzing noise. They keep concealed in the night, and are in motion only during the day.
* Lucanus Dama of Fabricius.
The larvæ are wood-eaters or borers. Our forests and orchards are more or less subject to their attacks, especially after the trees have passed their prime. The transformations of these insects take place in the trunks and limbs of trees. The larvæ that are known to me have a close resemblance to each other; a general idea of them can be formed from a description of that which attacks the pig-nut hickory. It is of a yellowish white color, very long, narrow, and depressed in form, but abruptly widened near the anterior extremity. The head is brownish, small, and sunk in the fore part of the first segment; the upper jaws are provided with three teeth, and are of a black color; and the antennæ are very short. The segment which receives the head is short and transverse; next to it is a large oval segment, broader than long, and depressed or flattened above and beneath. Behind this, the segments are very much narrowed, and become gradually longer; but are still flattened, to the last, which is terminated by a rounded tubercle or wart. There are no legs, nor any apparatus which can serve as such, except two small warts on the under side of the second segment from the thorax. The motion of the grub appears to be effected by the alternate contractions and elongations of the segments, aided, perhaps, by the tubercular extremity of the body, and by its jaws, with which it takes hold of the sides of its burrow, and thus draws itself along. These grubs are found under the bark and in the solid wood of trees, and sometimes in great numbers. They frequently rest with the body bent sidewise, so that the head and tail approach each other. This posture those found under bark usually assume. They appear to pass several years in the larva state. The pupa bears a near resemblance to the perfect insect, but is entirely white, until near the time of its last transformation. Its situation is immediately under the bark, the head being directed outwards, so that when the pupa-coat is cast off, the beetle has merely a thin covering of bark to perforate, before making its escape from the tree. The form of this perforation is oval, as is also a transverse section of the burrow, that shape being best adapted to the form, motions, and egress of the insect.
Some of these beetles are known to eat leaves and flowers, and of this nature is probably the food of all of them. The injury they may thus commit is not very apparent, and cannot bear any comparison with the extensive ravages of their larvæ. The solid trunks and limbs of sound and vigorous trees are often bored through in various directions by these insects, which, during a long.continued life, derive their only nourishment from the woody fragments they devour. Pines and firs seem particularly subject to their attacks, but other forest-trees do not escape, and even fruit-trees are frequently injured by these borers. The means to be used for destroying them are similar to those employed against other borers, and will be explained in a subsequent part of this essay. It may not be amiss, however, here to remark, that woodpeckers are much more successful in discovering the retreats of these borers, and in dragging out the defenceless culprits from their burrows, than the most skilful gardener or nurseryman.
The largest of these beetles in this part of the United States is the Buprestis (Chalcophora) Virginica of Drury, or Virginian Buprestis. It is of an oblong oval form, brassy, or coppercolored; sometimes almost black, with hardly any metallic reflections. The upper side of the body is roughly punctured; the top of the head is deeply indented; on the thorax there are three polished black elevated lines; on each wing-cover are two small square impressed spots, a long elevated smooth black line near the outer, and another near the inner margin, with several short lines of the same kind between them; the under side of the body is sparingly covered with short whitish down. It measures from eight tenths of an inch to one inch or more in length. This beetle appears towards the end of May, and through the month of June, on pine-trees and on fences. In the larva state it bores into the trunks of the different kinds of pines, and is oftentimes very injurious to these trees.
The wild cherry-tree (Prunus serotina), and also the garden cherry and peach trees, suffer severely from the attacks of borers, which are transformed to the beetles called Buprestis (Dicerca) divaricata by Mr. Say, because the wing-covers divaricate or spread apart a little at the tips. These beetles are coppercolored, sometimes brassy above, and thickly covered with little punctures; the thorax is slightly furrowed in the middle; the wing-covers are marked with numerous fine irregular impressed lines and small oblong square elevated black spots; they taper very much behind, and the long and narrow tips are blunt-pointed; the middle of the breast is furrowed; and the males have a little tooth on the under side of the shanks of the intermediate legs. They measure from seven to nine tenths of an inch. These beetles may be found sunning themselves upon the limbs of cherry and peach trees during the months of June, July, and August.
The borer of the hickory has already been described. It is transformed to a beetle which appears to be the Buprestis (Dicerca) lurida* of Fabricius. It is of a lurid or dull brassy color above, bright copper beneath, and thickly punctured all over; there are numerous irregular impressed lines, and several narrow elevated black spots on the wing-covers, the tip of each of which ends with two little points. It measures from about six to eight tenths of an inch in length. This kind of Buprestis appears during the greater part of the summer on the trunks and limbs of the hickory.
Buprestis (Chrysobothris) dentipest of Germar, so named from the little tooth on the under side of the thick fore legs, inhabits the trunks of oak-trees. It completes its transformations and comes out of the trees between the end of May and the first of July. It is oblong oval and flattened, of a bronzed brownish or purplish black color above, copper-colored beneath, and rough like shagreen with numerous punctures; the thorax is not so wide as the hinder part of the body, its hinder margin is hollowed on both sides to receive the rounded base of each wing-cover, and there are two smooth elevated lines on the middle; on each wing-cover there are three irregular smooth elevated lines, which are divided and interrupted by large thickly punctured impressed spots, two of which are oblique; the tips are rounded. Length from one half to six tenths of an inch.
Buprestis (Chrysobothris) femorata of Fabricius has the first pair of thighs toothed beneath, like the preceding, which it resembles also in its form and general appearance. It is of a greenish black color above, with a brassy polish, which is very distinct in the two large transverse impressed spots on each wing-cover; and the thorax has no smooth elevated lines on it. It measures from four tenths to above half of an inch in length. Its time of appearance is from the end of May to the middle of July, during which it may often be seen, in the middle of
Buprestis obscura, F., found in the Middle and Southern States, closely resembles the lurida.
† Buprestis characteristica, Harris. N. E. Farmer, Vol. VIII. p. 2.