Classification of Bisects. 105 



lar to those of the aquatic worms. And the great and com- 

 plicated changes which they undergo, both in structure and 

 form, lead to a development which does not rank higher than 

 that observed among Coleoptera. Indeed, the soft wings of 

 Neuroptera indicate, in my opinion, a character of low deve- 

 lopment ; for their peculiar structure resembles more that of 

 the wings of the young butterfly, before passing into the con- 

 dition of the pupa, than that of the elytra. The wings of 

 Coleoptera, again, resemble more closely the condition of the 

 wings in the pupa of the butterfly, at the period when the 

 outer wing is hardened and soldered to the body, covering 

 the lower wings, which remain soft. I would, therefore, 

 without hesitation, place Neuroptera as the lowest order of 

 Mandibulata. 



Next might come the Coleoptera, followed by the Orthop- 

 tera ; for Hymenoptera, no doubt, rank highest in this divi- 

 sion. To satisfy ourselves that this is the case, we need only 

 consider the structure of their jaws, the upper pair of which 

 alone preserve the character of chewing insects, while the 

 lower are transformed into a kind of proboscis very similar 

 to that of Haustellata. Again, their larvae rank higher than 

 the larvse of either Neuroptera or Coleoptera. They are 

 for the most part larvae with aerial respiratory organs, and 

 in that respect, rank decidedly above those of Neuroptera, 

 and might be considered as of equal value with those of 

 Coleoptera. 



Though the fact, that many Hymenoptera have caterpillar- 

 like larvae, will at once place them one stage higher, that is, 

 nearer the Haustellata, some facts presently to be mentioned, 

 respecting the changes which caterpillars undergo before they 

 pass into the state of complete pupae, will establish more fully 

 the value of this argument. 



There is, however, one order of chewing insects, the posi- 

 tion of which is somewhat embarrassing ; I mean the Orthop- 

 tera. If the views expressed above are correct, the very fact 

 of their having chewing jaws will place them among the 

 Mandibulata, below the Haustellata. But what is the pro- 

 per position to assign to them among Mandibulata ? They 

 cannot be placed higher than the Hymenoptera, for their 



