416 TRANSACTIONS OF THE 



prey voraciously upon the smaller and weaker insects, upon larvae 

 and worms, preferring those whose bodies are furnished with a 

 membranaceous cuticle, more readily permeable to their instru- 

 ments eibaria. 



The same rapacity is observable in the larva, or imperfect stage 

 of existence, of these insects, that we have occasion to remark in 

 the parent; but not having been endowed by natui'e with the 

 same light and active frame of body, they are under the neces- 

 sity of resorting to stratagem and ambuscade for the acquisition 

 of the prey, which is denied, to their sluggish gait. The remark 

 is, I believe, generally correct, though liable to many signal ex- 

 ceptions, that carnivorous animals display more cunning, industry, 

 and intelligence, than those whose food is herbs, for the acquisi- 

 tion of which, fewer of the mental attributes are requisite ; we 

 see throughout the animated creation, that the development of 

 these qualities, as well as of the corporeal functions, are in exact 

 correspondence with their necessities ; and that where a portion 

 of the one is withheld, an additional proportion of the other is 

 imparted. This larva has a very large head, elongated abdomen, 

 and six short feet placed near the head ; when walking, the body 

 rests upon the earth, and is dragged forward slowly by the feet. 

 Notwithstanding these disadvantages they contrive means to ad- 

 minister plentifully to an appetite, sharpened by a rapid increase 

 of size. A cylindrical hole is dug in the ground to a consider- 

 able depth, by means of the feet and mandibles, and the earth 

 transported from it, on the concave surface of the head; this cell is 

 enlarged [403] and deepened, as the inhabitant increases in size, 

 so that its diameter is always nearly equal to that of the head. At 

 the surface of the earth they lay in wait for their prey, nicely 

 closing the orifice of the hole by the depressed head, that the 

 plain may appear uninterrupted ; when an incautious or unsus- 

 pecting insect approaches sufficiently near, it is seized by a sudden 

 effort of the larva, and hurried to the bottom of the dwelling, to 

 be devoured at leisure. These holes we sometimes remark, dug 

 in a footpath ; they draw the eye by the motion of the inhabitant 

 retreating from the surface, alarmed at the approach of danger. 



I shall now proceed to offer some remarks on the affinities of 

 this genus, and endeavor to point out the differential traits, by 



[Vol. I. 



