28 



ON THE ORIGIN AND 



[CHAP. 



or plants, are vermiform, as are those which live in 

 cells, and depend on their parents for food. On the 

 other hand, larvae which burrow in wood have strong 

 jaws and generally somewhat weak thoracic legs ; 

 whilst those which feed on leaves have the thoracic 

 legs more developed, but less so than the carni- 

 vorous species. Now, the Hymenoptera, as a general 

 rule, belong to the first category : the larvae of the 

 Ichneumons, &c., which live in animals, those of 



and eandez-, Mem. boc. Koy. Liege, 1853;. 0. 

 (Packard, Guide to the Study of Insects, Fig. 403). 



the Cynipidse, inhabiting galls, and those of ants, 

 bees, wasps, &c., which are fed by their parents, are 

 fleshy, apodal grubs ; though the remarkable fact 

 that the embryos of bees in one stage of their de- 

 velopment possess rudiments of thoracic legs which 

 subsequently disappear, seems to show, not indeed 

 that the larvae of bees were ever hexapod, but that 

 bees are descended from ancestors which had hex- 



