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ENTOMOLOGY.

and flat. The insects of this genus are found in sandy situations in May, June, and July. Genus 10, Coccinella.-Antennæ club-shaped; club solid, the palpi maxillary, and terminated by a large hatchet-shaped joint; body hemispherical; breast and wing-cases marginated; abdomen flat. This is the genus commonly known by the name of the lady-bird. So great is the variety of species in this genus, that on close examination scarcely three specimens will be found alike. Small as are these insects, they are difficult to destroy; without injuring their shape and beauty, they will bear a long immersion in spirits, and though they appear dead, will afterwards recover. Mr. Kirby, I observed on my study window a 'One morning,' says little lady-bird, yellow with black dots (coccinella twenty-two punctata L.) You are very pretty, said I to myself, and I should like to have a collection of such creatures. seized my prey, and not knowing how to destroy Immediately I it, I immersed it in geneva; leaving it in this situation a day and a night, and seeing it without motion, I concluded it was dead, and laid it in the sun to dry. It no sooner, however, felt the warmth than it began to move, and afterwards flew away. From this time I began to attend to insects.' The larvæ of this genus feed chiefly on the aphides or plant-lice, and are very serviceable in clearing vegetables of the myriads with which they are often infested.

'As the locust-eating thrush,' says Mr. Kirby, 'accompanies the locusts, so the coccinella seems to pursue the aphides; for I know no other reason to assign for the vast number that are sometimes, especially in the autumn, to be met with on the sea-coast, or the banks of large rivers. Many years ago those of the Humber were so thickly strewed with the common lady-bird (C. septem punctata, L.) that it was difficult to avoid treading upon them. Some years after wards, I noticed a mixture of species, collected in vast numbers on the sand-hills on the seashore, at the north-west extremity of Norfolk. My friend, the Rev. Peter La'hbury, made, long since, a similar observation at Oxford, on the Suffolk coast; and about five or six years ago they covered the cliffs, as I have before remarked, of all the watering places on the Kentish and Sussex coasts, to the no small alarm of the superstitious, who thought them forerunners of some direful evil. These last probably emigrated with the aphides from the hop-grounds. Whether the latter and their devourers cross the sea, has not been ascertained; that the coccinella attempt it, is evident from their alighting upon ships at sea, as I have witnessed myself.'

Genus 11. Tritoma, Fabr.-Antennæ clavated; club perfoliate; lip emarginate, anterior; palpi hatchet-shaped; thorax flat. body greatly raised;

Of this genus there is but one British species T. bipustulatum, which inhabits fungi; the color is black, with a scarlet ring on the shoulder of the wing-cases.

Class II.-Antenna filiform, or of equal thickness throughout.

Genus 1. Bruchus.-Antennæ filiform; palpi

filiform and equal; lip pointed. This genus is period of their growth; indeed, so perseververy destructive to peas, particularly at a late ingly laborious is the female, that she will frequently deposit an egg in every pea of the pods she visits, and thus entirely destroy them. In this country, their numbers being small, the damage is seldom very considerable; but in most alarming ravages, so as, in some instances, North America the bruchus pisi commits the to destroy all hopes of a crop. No wonder then,' observes Mr. Kirby, 'that Kulin should have been thrown into such a trepidation upon vering some of these pestilent insects in a parcel discolest he should be the instrument of introducing of peas he had brought over from that country, so fatal an evil into his beloved Sweden. In 1780 an alarm was spread in some parts of France, that the people had been poisoned by fore, forbidden to be sold, but the fears of the eating worm-eaten peas, and they were, therepublic were removed by the discovery that it was a species of bruchus that had bored the peas. Another species, B. pecticornis, devours the peas in China and Barbary, and a leguminous seed, much used when boiled as food for horses in India, known to Europeans by the name of gram, but in the Tamul dialect called koloo, and by he Moors cooltee, is the appropriate food of a fourth kind of bruchus, related male are pectinated, much shorter than the body. to the last, but having the antennæ, which in the parcel of this seed brought over to this country This is perhaps B. scutellaris, of Fabricius. A by captain Green was filled with the insect, and several of the grains contained two or more of the larvæ. The plant appears to be a kind of phaseolus, from the peculiarity of the foliage.'

wing-cases and thorax marginated; head mostly Genus 2. Cassida.-Antennæ moniliform; covered by the thorax; body gibbous above, flat and marginated beneath. there are several British specimens, whose colors, Of this genus though brilliant and beautiful in the live insect, fade, and in some instances totally disappear after its death. The larvæ of these insects are peculiar for their Hottentot habit of covering themselves from the rays of the sun, and probably from the birds, by a parasol formed of their own excrements, and they are also furnished by nature with an apparatus, by means of which they can raise or drop their cove at their convenience. The instrument by which they effect this, says Mr. Kirby, is an oval fork, upon which they deposit their excrement, and which backs; at others forms different angles, from is sometimes turned up, and lies flat upon their very acute to very obtuse, with their body; and occasionally is unbent, and in the same direction on the back of the last segment of the body, with it. Its anus is remarkably situated, being and not at or under its extremity, as obtains in most insects. By means of such a position, the excrement, when it issues from the body, instead above the back in the direction of the head. of being pushed away and falling, is lifted up is retained, though slightly, by its viscosity. The When entirely clear of the passage, it falls, and

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grub next, by a movement of its segments, conducts it from the place where it fell, to the vicinity of the head. It effects this by swelling the segment on which the excrement is deposited, and contracting the following one, so that it necessarily moves that way. Although, when discharged, it has a longitudinal direction, by the same action of the segments the animal contrives to place every grain transversely. Thus, when laid quite bare, it will cover itself in about two hours. There are often many layers of these grains upon the back of the insect, so as to form a coat of greater diameter than its body. When it becomes too heavy and stiff, it is thrown off, and a new one begun. The cassida bidens is remarkable for two curious horns, one within another, that rise perpendicular from the centre of the sutures of the elytrum, and thus give a very peculiar appearance to the creature.

Genus 3. Ptinus.-Antennæ filiform, the last joints slightly larger; thorax nearly round, not marginated; head partly concealed by the thorax. The genus Ptinus, like that of dermestes, consists of small insects, which, in general, have similar habits, living both in their larva and complete state among dry animal substances, and some species of dry wood, committing much havock among the older articles of furniture, which they pierce with innumerable holes, thus causing a slow but gradual destruction. Mr. Curtis found the grub of the ptinus fur in a coat, which it alone had nearly destroyed, making holes and channels in all parts of it; and Linné tells us, that they will sometimes entirely deprive a fur of its hair. A remarkable property of this genus is, that, though their food is of so dry a nature, their bodies are always full of juices. A beam of oak, according to Messrs. Kirby and Spence, when it has supported the roof of a castle 500 years, is as much to their taste as the soft inner bark to the more epicurean dermestes, and they would sooner feast on the herbarium of Brunsfelsus than on the greenest herbs that grow. The grub of the ptimus will feed for months on a chair that has been baked before the fire for half a century, and from which the chemist's retort could scarcely extract a drop of moisture, and will yet have its body as well filled with fluids as that of a leaf-fed caterpillar. To this genus belong the well known death-watch, the ptinus fatidicus of Linné, the anobium tesselata of Fabricius. It is chiefly in the advanced state of spring that this alarming little animal commences its sound, which is no other than the call or signal by which the male and female are led to each other, and which may be considered as analogous to the call of birds; though not owing to the voice of the insect, but to its beating on any hard substance with the shield or fore-part of its head. The prevailing number of distinct strokes which it beats, is from seven to nine, or eleven; which very circumstance may perhaps add, in some degree, to the curious character which it bears among the vulgar. These sounds or beats are given in pretty quick succession, and are repeated at uncertain intervals: and in old houses, where the insects are numerous, may be heard at almost every hour of the day; especially if VOL. VIII.

the weather be warm. The sound exactly resembles that which may be made by beating moderately hard, with the nail on the table. The insect is of a color so nearly resembling that of decayed wood, viz. an obscure grayish brown, that it may for a considerable time elude the search of the enquirer. It is about a quarter of an inch in length, and is moderately thick in proportion, and the wing-shells are marked with numerous irregular variegations of a lighter or greyer cast than the ground-color. Ridiculous, and even incredible as it may appear, it is an animal that may in some measure be tamed; at least it may so far be familiarised as to be made to beat occasionally, by taking it out of its confinement, and beating on a table or board, when it will readily answer the noise, and will continue to beat as often as required.

We must be careful not to confound this animal, which is the real death-watch of the vulgar, emphatically so called, with a much smaller insect, of a very different genus, which makes a sound like the ticking of a watch, and continues it for a long time without intermission. It belongs to a totally different order, and is the termes pulsatorium of Linnæus.

Genus 4. Chrysomela.-Antennæ moniliform; palpi six; thorax marginated, but not the elytra; body ovate. The insects of this genus are noted for their shining and splendid colors, they live principally on leaves, but do not eat the nerves or fibres. Their larvæ are in general of an oval shape, somewhat elongated and soft, with six feet near the head. In the larva state they also feed on the leaves of trees and plants, the pulp and tender parts of which they devour, rejecting the fibres; some kinds infest the cotyledons only, and are very destructive. In the perfect state, they are found chiefly in woods and gardens. Many of these insects are slow in motion, but some kinds have the posterior legs formed for leaping, and some of them, when caught, emit an oily liquor of a disagreeable smell. See CHRYSOMELA in the body of this work.

Insects of this genus mostly ascend plants by means of the cushions of hair with which the underside of the joints of their tarsi is covered, and the C. tenebricosa (bloody-nosed beetle), and the C. goellingensis, will, with these curious supporters, walk with their back downwards, thus supporting themselves against the attraction of gravity. One of the most remarkable species is the C. populi, having the body ovate; thorax bluish; elytra red, tipped with black. This insect inhabits Europe generally, and destroys the leaves of the ash and poplar. But the most remarkable peculiarity is exhibited by the larva, which is varied with black and white, and furnished with very peculiar scent organs. On each of the nine intermediate dorsal segments of its body, is a pair of black elevated conical tubercles, of a hard substance; from all of which, when touched, the animal emits a small drop of a white milky fluid, the smell of which, De Geer observes, is almost insupportable, being inexpressibly strong and penetrating; and, as the drops proceed at the same instant from all the eighteen horns, they form a curious spectacle. The insect, however, does not waste this pre

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cious fluid; each drop, instead of falling, after appearing for a moment, and dispensing its perfumes, is withdrawn again within its receptacle till the pressure is repeated, when it reappears.' Kirby and Spence, vol. ii. 246. From this genus Fabricius separates the genus CRYPTOCEPHALUS, which see.

Genus 5. Hispa.-Antenna cylindrical, approxirate at the base, and seated between the eyes, polpi fusiform, thorax and elytra spinous generally.

Most of the hispa genus are natives of extra European climates; those found in Europe occur in the winged state on the leaves and roots of different kinds of grass; their larvæ and transformations are unknown.

The four species of the hispa tribe known to Linnæus, were atra, testacea, sanguiniollis, and mutica, the last of which was not however then considered as appertaining to that genus, being referred by Linnæus to the dermestes family, under the specific name of clavicorns. This is however now replaced with the hispa, and the number of species is about twenty-five.

Genus 6. Meloe.-Antenna moniliform, thorax nearly round; elytra soft, flexible, and shorter than the abdomen; head inflected and gibbous.

This genus is mostly found in spring, feeding on the ranunculus, or in open sandy fields, and its ova have an agreeable smell. This tribe is found from Sweden and Spain to Russia, and the shores of the Mediterranean. Of registered species, Britain possesses the largest proportion; but there are thought to be more in Spain. The most remarkable species is the meloe proscarabæus (oil-beetle), having deep yellow drops of an animal oil at all its joints. As these insects feed upon acrid plants, such as the crowfoot or ranunculus, it is probable that this fluid partakes of the nature of their food, and is very acrimonious, and thus may put to flight its insect assailants or the birds, from neither of which it could otherwise escape, being a very slow and sluggish animal. The larvæ of this insect are said to be parasitical, upon the authority of De Geer. He observed, according to Mr. Kirby, the insect deposit in the earth one or two considerable masses, containing an infinite number of very minute orangecolored eggs, adhering to each other, which in about a month were hatched, and produced a number of small hexapods, distinguished by two pairs of anal setæ and a proleg, by means of which they could move readily upon glass, as I have myself seen these little animals precisely corresponded with one found by the latter author upon syrphus intricaria; and, when that fly was placed amongst them, they immediately attached themselves to it, so as to leave no doubt of their identity. A congenerous species had been detected upon wild bees, and described by Linné under the name of pediculus apis. De Geer is so thoroughly to be depended upon, for his veracity and accuracy of observation, that we cannot suppose there is any incorrectness in his statement. If the mass of eggs be, as he represents it, of the size of a hazel nut, it must have been the product of a very large insect: in confirm ation of this opinion it may be further observed, that the larva of the kindred genus cantharis Lat.

agrees with it in having anal setæ, though it appears to differ in having only two conspicuous segments in the trunk. Those which infest wild bees, make their first appearance upon acrid plants, which the meloe likewise feeds upon; from whence with wonderful agility they leap upon the andrenæ that visit these flowers. Still, however, it is so contrary to the analogy of nature for the larva of the great beetle to feed on the little bee, and that these creatures should be for the first part of their lives fed on insects, and afterwards on animal food, that it is much to be wished that some skilful insect-anatomist would carefully dissect the meloe; or, perhaps by digging round the roots of the ranunculusēs, and other acrid plants, the larva of that beetle might be discovered in a late stage of growth, and so this mystery be cleared up.

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This genus is distinguished by Fabricius from the notorus and lytta, and in this arrangement be is followed by Dr. Marsh; indeed the improvements of the writer first named, as noticed in this treatise, are almost universally adopted by the adherents to the Linnæan system.

The notorus is thus described:-antennæ filiform; feelers four, securiform; jaws having one tooth each. N. monoceros is remarkable as having the thorar projecting like a horn over the head. It may be often seen buzzing about the sea shores of Wales.

The characters of the lytta are antennæ filiform; feelers four; the hind pair clavated; thorar round; head bent down and gibbous; wing-cases soft and flexible. The well-known blistering fly (lytta vesicatoria) belongs to this genus. See LYTTA.

Genus 7. Tenebrio.-Antenna moniliform, last joint round; thorax slightly convex and marginated; head standing out; elytra somewhat rigid. A well-known species is T. molitor, which is entirely black; thighs anterior thick; an insect often seen in houses, proceeding from a larva commonly known by the name of meal-worm, from its being so frequently found in flour, &c.; it is of a yellowish-white color, about an inch long, slender-bodied, and of a highly-polished surface, and is considered as the favorite food of the nightingale, in its captive state, and said to remain two years before it changes into a chrysalis. The meal-worm, though its usual food is flour, has been voided both by male and female patients; and, in one instance, is said to have occasioned death. How these grubs should get into the stomach it is difficult to say, perhaps the eggs may have been swallowed in some preparation of flour. But that the animal should have been able to sustain the heat of that organ, so far exceeding the temperature to which it is usually accustomed, is the most extraordinary circumstance of all.

From this genus Fabricius has distinguished the BLAPS, which he thus defines :—Antenna filiform; palpi four; thorar slightly convex, and marginated; head standing out; wing-cases somewhat rigid; wings mostly wanting. The most noted species is the blaps-mortisaga. It is a coal-black insect, measuring about an inch in length, of rather slow motion, and distinguished by the remarkably pointed appearance of the

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