410 



ZOOLOGT. 



as wings form elytra, i. e., protecting sheaths for the others 

 (a, Fig. 426). At other times these same wings, still mem- 

 branous towards their extremities, become hard and opaque at 

 their base, and are then called semi-elytra. 



Fig. 425. Morphe. 



Fig. 426. Capricorne Charpentier. 



There are insects in which the wings, instead of being 

 laminated, are cleft into a number of membranes, barbed on 

 the edges like feathers, disposed like a fan. This may he 

 seen in the genus pterophore and orneode (Fig. 427). 

 Finally, when the posterior wings are wanting, they are 



V^ V/^/l 



Fig. 427. Orneode ; Plumed Moth. 



usually replaced by two small moveable filaments, terminated 

 like a club, and named balances (Fig. 428). 



517. The abdomen of insects is composed of a consider- 

 able number of rings, moveable on each other. As many as 



