352 



ZOOLOGY. 



Order 12. Coleoptera. The beetles form a homogeneous 

 and easily circumscribed group, all having the fore-wings 

 thickened, not used in flight, and forming sheaths (elytra 



Fig. 335 Pine weevil, a, larva ; b, pupa. 



or wing-covers) for the hinder pair. The mouth-parts are 

 free and adapted for biting. The metamorphosis is com- 

 plete. The young or larvaa of beetles are called grubs. 

 Examples of beetles and their transformations are the pine 



Fig. 336 June Beetle and its transformations. 1, pupa; 2, larva. After Riley. 



weevil (Fig. 335, Pissodes sirobi Peck) and the June beetle 

 (Fig. 336, Lachnosterna fusca Frohl.). The oil beetle is 

 remarkable for passing through three larval stages (Fig. 



