158 ON SYSTEMATIC ZOOLOGr. 



is first excluded by the female, and contains the insect 

 in its smallest state: from the egg is produced the larva, 

 grub, or caterpillar, of a moist soft substance, without 

 wings, slow in motion ; often with numerous feet, some- 

 times with none; sterile, and very voracious of its pro- 

 per food : from this state it passes into that of the 

 pupa, chrysalis, or nymph, which is drier and harder 

 than the last, confined in a narrow compass, naked or 

 enclosed in a web ; often without a mouth ; and some- 

 times with, sometimes without feet : escaping from this 

 last confinement, it becomes the perfect insect, furnished 

 with antennae. Such is the general definition given by 

 the illustrious Swede of the class Insecta. But we shall 

 gain a better insight into his views by looking to the 

 construction of his primary groups. 



(212.) The first divisions of the class are into seven 

 orders, as follows: — 



Modern Orders. 

 1. Coleoptera. f "^ings four ; the upper crustace- J coleoptera. 

 ^ (_ ous, with a straight suture. j v-v/ ^.^i,..>..o. _ 



" HemiDtera. f Wings four ; the upper semi-crus- 7 Hemiptera. 

 *" '^ i taceous and incumbent. J Homoptera. J 



J' 



r Wings four; all of them membra- ^ 

 3. Lepidoptera. •< naeeous and imbricate with line > Lepidoptera, 

 C scales. J 



fNeuroptera? 

 r Wings four, all of them membra- | Orthoptera. •' 

 i. Neuroptera. < naeeous and reticulate ; tail un— { Dermoptera. ' 

 C armed. i Trichoptera. | 



(.Strepseptera. 



s w„«,o„„«t„..„ f Wings four, all of them membra-lTj „„^ t„.„ 



5. Hymenoptera. ^ „^^^^^^ . '^^.^ ^^^^ ^.^^^ ^ ^^.^^_ j Hymenoptera. 



6. Diptera. ["^rngs two. with a poiser under j pj^^^^^ - 



Classes, 

 u f Suctoria ia<. 



Crustacea Lat. 

 Aptera Lat. 

 Myriapoda Leach. 



7. Aptera. ; ''Vitjgs none in either sex. ^ Thysanura Leach. 



I Ametabolia Leach. 

 I Arachnoida Leach. 

 I Acari Leach. 

 I &c. &c. 



(213.) On comparing these primary divisions with 

 those of Aristotle, we observe a marked improvement in 

 two essential points. The first regards the separation 

 of the Hymenoptera from the Neuroptera, both which 



