74 EXTERNAL ANATOMY OF INSECTS. 



solid, bony, and somewhat quadrate. Unlike the same part 

 in Diptera, it cannot be bent without injury. It either retains 

 the bend or it breaks. It is not always visible externally. 

 In the bee it is conspicuous : in the wasp it is hidden by the 

 clypeus. In Coleoptera it retains a similar character. It 

 varies much in development. The Scarabceites have the upper- 

 lip small. I cannot consider, with Olivier, that it is in any case 

 absolutely wanting, 6 although the great stag-beetle is almost 

 without it. In these orders f the clypeus supplies its place : 

 whence the error of Fabricius in confounding the two. In the 

 rapacious beetles it is large. In Anthia and Cicindela it is 

 very conspicuous. In all water-beetles it is fully developed ; 

 the difference in their economy does not affect it. g In Orthop- 

 tera its character continues the same, its relative size larger. 

 In Hemiptera it has changed. It continues rigid, and is 

 injured by bending : but it is longer and more pointed than in 

 the three preceding classes. It is grooved to receive the 

 labium, and is the only part of the mouth that is detached. 

 In Issus it is sharper than a needle. In the other Cicadites 

 it is more obtuse. In the Cimicites, again, it is sharp ; and the 

 same in the Nepites. The mouth in Neuroptera has no com- 

 mon character. Neuropterous orders, with the exception of the 

 central one, Libellulites, h assimilate in all their characters to 

 the classes to which they approach. I cannot, therefore, detail 



Idvre inferieure, comme celle des Hymenopteres, mais par les machoires. Dans 

 les Myodaires, elle est ordinairement membraneuse, quelquefois solides et 

 triarticulee. La base est enveloppee par la base de la levre inferieure, dont les 

 deux palpes sont toujours developpees, et qui se prolonge en deux supports 

 lateraux et ordinairement solides. Le corps de la trompe se prolonge en une 

 gaine, terminee par des levres membraneuses dues a des trach^es tres developpees, 

 et par des palpes qui peuvent etre solides. Elle renferme deux filets allonges 

 qui torment le sucoir et qui representent les mandibules. La piece plus ou 

 moins solides qui se prolonge sur la rainure de la trompe est le labre ou la levre 

 superieure. — Desvoidy. 



e Les Scarabies qui ont des mandibules, et qui n'ont point de levre supe- 

 rieure. — Olivier. 



f Scarabceites and Lucanites. 



e In water beetles the clypeus is never distinct. 



h La labre demi-circulaire voute ; deux mandibules ecailleuses, tres fortes et 

 tres dentees ; des machoires terminees par une piece de la meme consistance, 

 dentee, epineuse et ciliee au cote interieur, avec une palpe d'un seul article, 

 applique sur le dos, et imitant lagalete des Orthopteres, une levre grande, voutee, 

 a trois feuillets, et dont les lateraux sont des palpes ; une sorte d'epiglotte ou de 

 langue vesiculate et longitudinale dans Pinterieur de leur bouche. — Latreille. 



