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are dignified with the title of perfect? Who can from which junction a whitish nervous cord p1o. find an instance in any other creature that can ceeds, correiponding to the spinal mariow of the come in competition with this?"

fuperior animals, which extends the whole length On this dispute-we shall only observe, that the of the body, forming in its course twelve or thira wisdom of the Creator is to conspicuous in all his teen knots or ganglions, from each of wbich small works, and such surprising art is discovered in the nerves branch out to different pirts of the body. mechanism of the body of every creature, that it The existence of this medullary thread in the is very difficult, if not impofiibie to fay where it heads of insects is not denied by those who follow is moit, and where it is least, to be perceived. Linnæus, in afterting that infects have no brain,

Those who are defrous of attaining a systematic but they could never discover it to be organized knowledge of insects, ought firit to acquire the like the brain; and hence, say they, the hippoborterms made use of in the science, that they may ca equina, or horfe bly, will live, run, nay even be able rightly to denominate every part of an copulate, after being deprived of its head; to say infect. The student should first know what an nothing of many others which are capable of live infećt is, left he mistake HIPPOCAMPI, and o- ing long under the faine circumstances. But, he ther amphibious animals, for them, as was former- knots or ganglions which are formed in the coule dy done; or confound them with VERMES, which of the larger nerves, perform in a dat menire Linnxus first distinguished from intects, and which the function of the brain ; indeed each of thote ditter as efTentially from them as the class MAMMA- ganglions may be confidered as a fubordinate lia do from birds. Every infect is furnished with brain; and thus it may be easily conceived ...ow a head, antemæ, and feei, of all which the vermes the various parts which derive their nerves from are deftitute. All insects have fix or more feet; any one of these ganglions, Mould be enabled to they respire through pores on the sides of their perforin their diferent functions, after they have bodies, which are termed spiracula: their skin is been separated from the other parts of the body, extremely hard, and ferves them instead of bones, and deprived of ail connexion with thy brain. of which they have internally none. From this Infects not being apparently furnished with cars, definition, the acus marina is evidently no infect. they have been suppored to be incapable of hearBut the antennæ placed on the fore part of the ing; as we can no more conceive that lense to head constitute the principal diftinction. These exist without ears ihan vision without eyes. That are jointed and moveable in every part, in which they are nevertheless sulceptible of any ihrill or they differ from the horns of other animals : they loud noise, as well as fishes, is indisputable; but are organs conveying some kind of fenie; but we it has been fupposed to be in a nanner different bave no more idea of what this kind of sense is, from that of hearing. Mr Barbuit, however, thinks than a man has, who, without eyes, attempts to they poilefs this fense in a very distinct inaurer. determine the particular action of the rays or light Many infects, he obtörves, are well known to be on the retina of the eye, or to explain the changes endowed with the power of uttering suunds, fuch which from thence take place in the human mind, as large beetles, the bee, waip, cominon lly, gnat, That they are the organs of some kind of senie, &c. The sphinx atropos [que:iks, when hurt, *is apparent from their perpetually moving them nearly as loud as a mouse. Now, if iteets are forward; yet the hard cruit with which they are endowed with the power of uitering founds, it invested, and their shortnets in flies anci otherinteets, certainly mult be for some purpose. As they vary would induce ove to believe them not to be the their cry occasionally, it must certainly be defig:nigans of touch: Mr Barbut fupposes them to con- ed either to give notice of pleature or pain, or ttitute or to contain the organs of hearing That Tome atiection in the creature who poffeftes it. they are tubular, and filled with air and fome " The knowledge of their founds i he jully argues) kind of humour, appears from the antennæ of but- is undoubtedly confined to their tribe, and is a terlies immersed in water,

language intelligible to them only; saving when SECT. II. Of the EXTERNAL PARTS OF INSECTS.

violence obliges the animal to exert the voice of

nature in distref, craving compulion; then all The external parts of the bodies of infects, a- animals understand the doleful cry. For initance, greeably to the utual anatomical divilion of those attack a bee or wasp near the hive or velt, or a in larger animals, may be divided into the head, few of thein: the confequence of that affzult will trunk, abdomen, and extremities.

be, the animal or animais, by a different tone of I. Caput, the HEAD. It is asserted in the voice, will express his or their difapprobation or Funiamenin Entornologiæ, that this part in infects pain; that found is known to the hive to be plaina is without brain; but it is certain that a number tive, and that their brother or brethren require of the larger intects, as the lobster, crab, &c. have their allistance; and the offending party feldon a fost fubitance very much resembling brain, from efcapes with impunity. Now, if they had not which the optic and other nerves take their rile; the sense of hearing, they could not have known and the irritating of this subjtance is observed to the danger their brother or treibren were in by throw the animal into convullions; from which it the alteration of their tone." may be concluded, that infects, as weil as the A proof, llill more decilive, occurred to his ob. four fuperior clafles of animals, quadruperls, birds, fervation, in a large spider in St James's Park. reptiles, and fishes, have a brain, though it be This creature had made a very large web on a smaller in proportion to their body. The brain in wooden railing: and was, at the time he observed inost infects is situated a little above the æfopha- it, on one of the rails at a copliderai le distance gus; it dividea into two large branches which lur- from the place where a large fly entangled itself. round the æsophagus, and unite again under it, Neverthelets, the moment the Hy was entangled,

the

the spider became fenfible of it; though, from the palpi or feelers ; observing that the palpi are ia situation of the rail, he could not poflibly have continual motion, the animal thrusting them into feen it. In this, however, Mr Barbụt might por- every kind of matter, as a hog would do his nose, fibly be deceived ; because the spider was perhaps smelling and searching after food. The sense of alarmed by the tremulous motion of the threads, smelling is supposed by other naturalifts to relide occafioned by the fluttering of the Ay; which he in the antennæ: Bafter supposed it to be fituated amight well know how to distinguish from their vi- bout the entrance of the spiracula or respiratory bration by the wind. The organ of hearing, in our organs; and Dumeril published a dissertation, in author's opinion, is situated in the antennæ; both 1799, in which he attempts to prove this last to from their situation in the part of the head mot be its situation. But Latreille, who had adopted favourable to such organs, their inward ftructure the opinion of those who believe the antenna to being moveable, the ears of most inferior animals be the organs of smell

, in his Precis du Cara&are being so. lle has never considered the antennae des Genres, published in 1996, not withstanding the as either offensive or defensive, but has observed arguments of Dumeril, itill holds by his former them to be endowed with an exquisite sense of opinion, in another work, entitled les Genres et les feeling ; that the animal appeared to be in agony Familles des Insectes, fince published. The followwhen its antenna were pinched; and that it takes ing are his reafons for favouring this opinion: 1. care to avoid the touching any hard substance Smell is produced by the action of the air, impreg. with them roughly..“ This tenderness in the or. nated with odoriferous particles, on the nervous gan of hearing (says he) is common to all animals; or olfactory membrane, which transmits the senand insects seem to be particularly tender in these fation.--If insects be endowed with'an organ, fur. parts by quickly withdrawing them from the nished with similar nerves, adapted for receiving touch."

impressions from air charged with odoriferous parMr BARBUT further observes, that the antennæ ticies, such organ many be considered as that of of all insects are composed of joints varying in smell. Should the antennæ present a tissue of fize, form, and number. Those who are chiefly many nerves, why may not that tissue be sappof confined to live under water have their antenna ed capable of transmitting odour? Would not this in general Morter than those who live on land. idea be more simple, and more agreeable to anaSome who roam at large in !he air, have them tomical principles, than that which fixes the seat long and Nender. They are all hollow, and are ren- of smell

at the entrance of the spiracula ?--2. Madered flexible by the joints, which are very visible ny male insects have their antennæ more developed in the horns of the crab and lobster. This bol. than the females ; a circumstance easily explained, lowness, in our author's opinion, is to receive the if these organs are allowed to be the feat of smell. found communicated to the extremities of the an. 3. Certain it is, that moft of those insects which tennæ by the repercussion of the air affected by live or deposit their eggs on putrid animal or veany noise ; and convey it, by means of the joints, getable matters, ftagnant waters, &c. are almost from one to another, till it arrives in that lefsened uniformly distinguished by a greater developement degree of tone best suited to the timid nature of of the antennæ; such, for instance, as the beetle, the animal. In this circumstance there may be fylphs, leather-eaters, tipulæ, &c. These requirmany variations in point of perfection in those or- ing a more perfect sense of smell, arc suitably organs; the strength, utility, and degree of power ganized. 4. A great number of infects, which are in receiving found, being proportioned to the ne- entirely rapacious, have simple antennæ; and those <essities of the animals, different in their nature which are sedentary, have none at all; such are and requisites. In molt animals, the entrance to some of the spiders. 5. Infects discover their the auricular organ in patulous; but is this case haunts and food by the sense of smell. Latreille the animal would suffer great inconvenience from deprived several infects of their antennæ, and found such an organization, as the organ would often they instantly fell into a state of insensibility, and be clogged with dirt, &c.

seemed to know neither their habitations nor their However much it has been doubted by entomo- food, though placed close by them.' Were such logists, it seems very evident, that insects enjoy experiments as this prosecuted, the question might the faculty of smelling; nay, that it is the molt soon be decided: by coating the antennæ of insects perfect of all their lenses. Beetles of various forts, with varnish, and placing them near their natural nitidulæ, the different species of domestes, sylphs, food, it might ealily be known whether the anfries &c. are attracted at a very considerable distance, tenna were the organs of smell; if they were, the by the fmeil of ordure and putrid bodies, and re- aninal could not be fupposed to find its way to tort in swarms to the spots in which they occur, the food, and vice versa. 6. Nerves terminate the exther for the purpose of feeding or laying their antennæ, the articulations of which, though ex. eggs. Thus also the common blue Nem-ily, is al. ternally covered with a pretty thick membrane, lured by the strong smell of the aiarum dracuntium, are hollow, lined with a soft substance, frequent. which is much the same as that of carrion, and ly of a watery consistence, the cxtremities of which, deposits its eggs on it; in the fame manner, the when exposéd to the air, may receive impressions .cadaverous smell of the flowers of the papelia bir- from it. suta, leads these flies to deposit their eggs on them. The antenna have been supposed by some to be But, though it is thus evident that infects have a the organs of touch ; but this opinion is opposed perception of agreeable and fetid effluvia, ento- by Latreille, who seems to think that the fente of mologists are not at all agreed as to the seat of touch, at least in certain species, is situated in the that particular sense. Mr Barbut and others are paws or extremities of the fore legs. The palpi of opinion that the organs of limell reside in the or feelers in spiders and some other insects seem to

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possess the sense of touch in an eminent degree ; MAXILLÆ, the Jaws, are two in numbers but these palpi are considered by many rather as sometimes four, and at other times more; they the organs of tafte.

are placed horizontally; the inner edge of them in Tongue. Many infects have no tongue, nor some insects is serrated or furnished with little teeth. make any found with their mouth; but for this LINGUA, the Tongue, in some infects is taper purpose some use their feet, others their wings, and spiral, as in the butterfly; in others it is felly, and others fome elastic inftrument with which resembling a proboscis, and tubular, as in the fly, they are naturally furnished.

LABIUM superius, the upper Lin, is fruated Eres. Most insects have two; but the gyrinus above the jaws; as in the scarabæus and gryllus. has the scorpion 6, the spider 8, and the sco. STEMMATA, or Crowns, are three smoot': he. lopendra 31. They have no eye-brows, but the mispheric dots, placed generally on the top of the external tunic of their eyes is hard and transparent Head; as in most of the hymenoptera, and others. like a watch-glass ; their eyes have no external II. TRUNCUS, the TRUNK, is that par: which motion, unless it be in the crab. They confift for comprehends the breast or thorax: it is situated the most part of one lens only; but in those of between the head and abdomen; and has the legs the butterfly, dipteræ, and many of the beetles, inserted into it, that its parts may be distinctly they are more numerous. Pugett says, he disco determined. It is divided into thorax, scuteilum, tered 17.335 lenses in the cornea of a butterfly, and sternum. and Lieuwenhoek 800 in a fly.

The THORAX is the back part of the breast, ANTENNÆ. Of these there are in general two and is very various in its shape. It is called den(unless 4 are allowed to some species of crabs), tatus, when its Gdes are armed with points; spin and placed on the fore-part of the head. They nosus, when its back is furnished with them as in are peculiar to insects, and are plainly distinguish- the cerambyx; and marginatım, when its margin able from the tentaculæ of the vermes, in being is laterally dilated, as in the filpha and caffida. crustaceous; and from the palpi of infe&ts, which SCUTELLUM, or Escutcheon, is the posterior: are more numerous, placed near the mouth, and part of the thorax: it is frequently triangular; and are sometimes wanting. As the antennæ are of appears to be divided from the thorax by an ingreat moment in distinguishing the various kinds tervening suture, as in most of the coleoptera. of insects, we shall enumerate and explain the se- The STERNUM is situated on the inserior part Feral different forms of them.

of the thorax; it is pointed behind in the elateres, Setacre, are those which grow gradually taper and bifid in some of the dytisci. towards the extremity. , Filiformes, such as are III. The ABDOMEN is in most infects distinct of the same thickness throughout. Moniliformes, from the thorax; it is the posterior part of the are filiform, like the preceding, but consist of a body of the infect; and is composed of a number, series of round knobs, like a necklace of beads. of annular segments, which serve occasionally to Clavată, such as gradually increase in fize toward lengthen or shorten it, and to contain the organs the extremity. Capitaté are clavate, but have of chylification, &c. the extremity somewhat round. Fifiles are capi. SPIRACULA are little holes or pores, placed tate; but have the capitulum, or knob, divided singly on each side of every segment of the abdo. longitudinally into 3 or 4 parts, or laminæ, as in men; through these the infect breathes; and if the scarabæi. Perfoliate are also capitatce; but oil be applied fo as to flop them up, it proves fahave the capitulum horizontally divided, as in the tal to most of them. dermestes. Peštinata, fo called from their fimili- TERGUM, the Back, is the superior part of the tude to a comb, though they more properly re- abdomen... semble a feather, as in the moths and elateres. VENTER, the Belly, is the inferior part. This is most obvious in the male. Arisatą, such ANUS, is the posterior part of the abdomen, as have a lateral hair, which is either naked or perforated for the evacuation of the excrement. furnished with leffer hairs, as in the fly; Brevio. This part also frequently contains the organs of res, those which are shorter than the body : Lone generation. giores, those wbich are longer than the body; me. IV. Artus, the Limbs, or EXTREMITES, diocres, those which are of the same length with are the various instruments of motion. the body; all three of which varieties are distin- PEDES, the Legs, are generally fix. There is guishable in the cerambyces.

an exception to this, however, in the class AptePalpi, or Feelers, resemble filiform, articula. ra, many of which have 8 ; as acari (mites, phated, moveable antennæ. They are most com- langii, most of the aranei (spiders), scorpiones, monly 4 in number, sometimes 6; they are suffi- and cancri (crabs.). The oniscus has 14, and the ciently diftinguished from antennæ, in being na- iúli and scolopendri ftill more. ked, ímort, and always placed at the mouth. The first joint of the leg, which is generally

Os, the Mouthis generally placed in the an. thickest, is called femur ; the ad which is generally terior part of the head, extending somewhat downic of the same fize throughout, tibia; the 3d, which wards.

In some infects it is placed under the is jointed, is distinguished by the name of torsus; breaft, as in the chermes, coccu's, cancer (crab), and the last, which in mot infects is double, by and curculio.

that of unguis. The legs of in eis, in general, are ROSTRUM, or Proboseis, is the mouth drawn named from the various motions they produce out to a rigid point: in many of the hemiptera Cursorii, from that of running, which are the most class it is bent downward toward the breast and numerous; saltatorii, from that of leap ng ; natobelly, as in the cicada, nepa, not one&ta, cimex(bug), torii, from that of swimming, &c.- In the saltoaphis, and remarkably To in some curculiones. torii, the thighs are remarkably large, by which Vol. IX. PART I.

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means they are able to leap to a considerable dir. Flytri, the plural of elytron. The upper rings, tance, as in she fryllus, grasshopper, &e. In which are of a hard fubilance, in foine de ce rethose of the nitatori, the feet are liat, and edged femabling leather, and which in most inficts are with hairs, which aniwer the purpose of oars in of a very hard texture, but in others flexible, are allittig them to swim, as in the detifcus -- Miucio called ilytra; their fuperior futace is generally ri, are furch feet as have no claws. ---Chat, or Corrix, their inferior one concave. When the claws, are the fore fect enlirged towards their ex. iabe sit flies, they are extinde; and lhut when it tremities, each of which is furnished with two leto prís, ciuling together, and forming a longitudinal fer claws, which act like a thumb and finger; as future down the middle of the lack, as in the coin the crab.

leoptera. They are of various lapes. ribbre visite, AL 4, Wings the struinents which enabsic the when fhorter than the abdomen. Truncata, whea infect to fiy. These are membranous and individ. longer than the abdomen, and terminating in a ed, excepi in the instance of the plænæ ahi. tanívente live.

Fiftigiata, when of equal or cite, in wrich they are in part divided. Most in. greater length than the abdomen, and terminating fects have 4 ; the diptera cls, and the coccus, in a transverse lirie. Serrota, when the exterior horvever, have only tivo. The wing is divided margin towards the apex is notched or ferrated, into its fuperior and interior furfaces: its anterior as in some of the bupreites. Spinosa, when their part in a butterfly, is that towards the anterior surface is covered with iharp points or prickles. margin, or next to the head; its posterior part, Sogérii, whin their furface is 10 uneven as to grate that towards the anus; its exterior part. that to. against the fingers. Strict, when marked with wards the outer edge; and the interior, that next Dender longitudinal surrows. Porcata, vben with the abdomen.

elevated longitudinal fuíci or riges. Sulcatel, The Ale are called Plicariles, when they are wiscn these rielges are concave. Hernelytra, when folded at the time the infeet is at rest, as in the the superior wings are of a middle fubftance bewasp; oppolite to there are the phone, which are twixt leather and membrane; either totally fo, as incapable of being tolded. Er&!e, such as have in the grylli; or partiaily so, as in the cimices, their superior furfaces brought in contact when repr, and notonectæ: These are commonly nathe infect is at reit; as in the ephemera, libeliu'a med kemittere. prella and virgo, and papiliones (butterflies.) Holteres, poilers, (a term also introduced by Patentes, such as remain horizontally extended Linnæus), are little headis placed on a staik or when the inf.ct is at rett; as in the phalænegeo- peduncle, mot frequently under a little arched metræ, aud mct of the libellulæ. Incumbentes, scale. They are found only in the class diptera, such as cover horizontally the superior part of ite and appear to be nothing more than the rudiments abdomt when the infidiis at ritt. D. fexe are of the lincier winys. incumbentes, but not forizontally, the onter CAUDA, the Tail, in most infects is, Simplex, euves declining towards the fides. Rezerfit, are simple, capable of being extended, and again deflexż, with this addition, that the edge of the drawn back at pleasure. In the crab and scor. inferior wings projects from under the anterior pion, however, it is Elongat, elongated, or part of the fuperior ones. Dintate are those in lengthened out. Setacea, bristle-shaped, or tawhich the edge is íerrated, or scoiloped: Coudats", per; as in the raphidea. Trijeta, coniling of those in which one or more projections in the three briftles; as in the ephemera. Turcata, forkhinder wings are extended into procesies. Reticu. ed, as in the podura. Forcipata, resembling a Intal", when the vellels of the wings put on the ap- pair of forceps; as in the forsicula. Foliola, repuarance of network, as in the hemerobins peria; fembling a leaf; as in the blatiæ, grylli, and forre the two anterior wings generally become supc. species of cancri. Telifora, armed with a dart cr rior, and the posteriör ones inferior, in moths, fing; as in the scorpion and parorpa. Aculus, when their wings are clofed; but the anterior the fting, an instrument with which they wound, wings are called primary, and the inferior ones and at the same time init il a poison ; with such secondary, in butterflies, as none can properly be the bee, walp, fcorpio., &c. are furnished, called inferior, when the wings are all erect.

EXPLANTION of PLATE CXXVI. Colores, the colours, are self-apparent and variol's; but according to their several tapes, they Fig. 1. ANTENNE PECTINAT.E, or feathered antake the different names of purls, dots; macıilet, tennæ; as in the phalana, moths. {pots; fasclx, bands, which frequently run across 2. ANTENNE PER FOLIATE, or pertoliated; as in and sometimes surround the edge of the wings; the derinesti's and dyt:fius. frige, streaks, which are very slender facfciæ; 2. ANTENNE FISSILES, or fittile, divided into 1.2and linex, lines, which are longitudinally exterded. inirx at the extremity, as in the searabxi,

Ocelluis, is a round fpoi, containing a letler spot beetles. of a difierent colour in its centre. Sigma, ano- 4. ANTENNÆ CLAVATÆ, or club-maped, as in the ther term introduced by Linnæus, signifies the papilio, butterfly. fout, or anatamosis, in the middle of the wing 5. ANTENNE MONILIFORMEs, like a necklace of far the anterior margin; it is copipicuous in beads; as in the chryfanel. most of the hymenoptera' ane neiroptera, and 6. ANTENNE SETACIÆ, letaceous, or bristleeen in the coicoptcra. Tlie single or double kid.

thaped; as in many of the phalene. ney-shaped spot, situated in the same part of the 7. ANTENNA ARISTITÆ, furnithed with a lateral anterior wings, and frequently occuring in the hair, as in the fly. plaaniæ pazanæ, is diftinguiihed likewise by the 8, 9, a Caput, the head. b Palpi, the feelers. name of j'iyina

c Antenne, or horns. & Oculi, the eyes.

e Thorax

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