ENTOMOLOGY. 



diocres, of the same length with the 

 bo.ij 



Cv vier has shewn that the organs of 

 hearing are placed at the base of the 

 antennae i:* the Crustacea, such as crabs 

 and lobsters, and from analogy many na- 

 turalists have supposed them to be simi- 

 larly situated in the true insects; this 

 may probably be correct, but it has not 

 yet been proved, and must not therefore 

 be assumed. 



Clypeus, the covering of the head in 

 the beetle tribe ; it extends from the eyes, 

 often projecting over the mouth. 



Vertex, the top of the head above the 

 front. 



Front, this term is applied to the an- 

 terior part of the head of most insects, 

 and is analogous to the clypeus of the 

 beetles. 



Gula, throat, underneath the head, sup- 

 porting the lip. 



Mouth, is situated in the head, rarely 

 in the breast, and affords so great a' 

 variety of characters, that the celebrated 

 Fabricius founded upon them his entire 

 system of arrangement ; the principal and 

 most obvious parts are, the palpii, mandi- 

 bulae, labrum, labium, ligula, maxillae, and 

 galeae. 



Palpi, or feelers, are articulated fila- 

 ments of different forms, sometimes re- 

 sembling antennae, placed in the mouth, 

 either on the jaws or lip ; they are two, 

 or four, or six, in number, and are either 

 anterior, intermediate, or posterior, or, 

 according to Latreille, labial or maxillary. 

 Considered in relation to those parts upon 

 which they are situated, they generally 

 furnish good generic characters. 



Mandibulae, mandibles, two horny curv- 

 ed pieces, placed one on each side of the 

 mouth, moving laterally, and used by the 

 insect either to seize its food, or as" wea- 

 pons in its combats. 



Maxillae, jaws, two horny or submem- 

 branaceous pieces, placed one under each 

 mandible, generally ciliated with hair, or 

 dentate on the inner side, and always pal- 

 pigerous in those insects that have more 

 than one pair of palpi. 



Labrum, or as it is sometimes termed 

 labium superius, upper lip, a transverse 

 moveable piece, placed immediately be- 

 low or underneath the clypeus and above 

 'he mandibles. 



Labium, lip, termed by some entymo- 

 logists labium inferius, and by others 

 mentum, or chin, a horny substance, 

 sometimes truncate, and terminates the 

 mouth ; beneath it supports the posterior 

 palpi, and serves as a sheath for the 

 *ongue. 



Ligula, a soft instrument, coriaceous 

 at the base, often bifid at the tip, and re- 

 tractile ; this part is found only in insects 

 provided with mandibles. 



Galas, casque, two membranaceous, in- 

 articulate pieces, placed one on each side 

 of the mouth in some insects of the 

 hemiptera and neuroptera orders, and in 

 conjunction with the lips covering the 

 mouth ; this part is by some considered 

 as an anterior palpi, or an exterior divi- 

 sion of the jaws. 



In some insects the mouth is elongated 

 into a tube, or placed at the end of a pro- 

 jection of the head, and is then either a 

 lingua, proboscis, haustellum, rostellum, 

 or rostrum. 



Lingua, tongue, soft, flexible, tubular, 

 involuted, like the spring of a watch, 

 usually obtuse at its termination, and 

 placed under the head between the palpi 

 of the butterflies and moths. 



Proboscis, trunk, soft, retractile, inar- 

 ticulate, labiated at the extremity, and is 

 peculiar to the flies ; the common fly af- 

 fords a good example of it. 



Haustellum, sucker, composed of very 

 fine and rigid filaments, enclosed in a 

 bivalve sheath, and is peculiar to the 

 cimices, and some of the flies. 



Rostellum, a bill, or beak, coriaceous, 

 articulate, and inclosing the haustellum. 



Kostrum, a prolongation of the head, 

 terminated by the mouth, as in the cur- 

 cuhos, &c. 



Some of these terms are not used by 

 some authors as here defined ; and in- 

 deed so unsettled are many entomologi- 

 cal terms, that the student is often very 

 much perplexed by the various applica- 

 tions of them. 



II. Truncus, the trunk, to which the 

 legs are attached, is situated between the 

 head and the abdomen ; it is divided into, 

 1. The thorax, or chest, which is the 

 superior part. 2. Scutellum, i. e. small 

 shield or escutcheon, separated from it 

 by a suture, on the posterior part. 3. 

 The breast and sternum, which is the in- 

 ferior part. 



III. The abdomen, that part which con- 

 tains the stomach, intestines, and other 

 viscera, consists of several annular seg- 

 ments ; it is perforated on the sides with 

 spiracula, or breathing-holes ; the upper 

 part of it is termed tergum, or back ; the 

 inferior part venter, or belly ; the pos- 

 terior part anus. 



IV. Artus, the extremities, are the 

 wings, legs, and tail. 



(1.) Ate, the wings, are two or four ; 

 they are either, J , Plan^e, *. e. plain, swell 



