32 



SCHOOL ENTOMOLOGY 



when there is no sharply defined resting stage, as the 

 pupal stage, the development is still said to be direct. 



FIG. 17. Chrysalids of Butterflies. 



1, 2, Papilionidce; 3, Pieridce; 4, NymphalidasS 



In almost all cases where the development is direct the 

 young forms have compound eyes, but larvae, properly 



FIG. 18. Larvae of the House-fly. Enlarged. 



speaking, never have more than ocelli and are often en- 

 tirely blind. This will ordinarily serve as a distinctive 

 point in cases of doubt. 



