158 



ENTOMOLOGY 



206) ; while male Coccidse have what is essentially a complete 

 metamorphosis. In fact, the various kinds of metamorphosis 



FIG. 205. 



Six successive instars of the squash bug, Anasa tristis. x 2. 



FIG. 206. 



Cicada tibicen. A, imago emerging from nymphal skin; B, the cast skin; 

 C, imago. Natural size. 



grade into one another in such a way as to make their classifi- 

 cation to some extent arbitrary and inadequate. 



