24 EXTERNAL STRUCTURE OF INSECTS 



place. Butterflies (Fig. 28) are day fliers; their antennae or feelers 

 are thread-like, with a knob on the end. Injurious forms in this 

 order are the codling moth (Fig. 29), currant borer, cut- worms, 

 army worm, and others. The pupal stage of butterflies is naked 

 and called a "chrysalis" (Fig. 30). The pupa of a moth is 

 inclosed either in a silken cocoon or in a cell below the surface 

 of the ground. 



Other Groups. Insects in an order are divided into families; 

 each family is divided into genera; each genus into species, and we 

 frequently have varieties of a species. These groups and sub- 

 groups are used in classification. 



QUESTIONS 



1. What is the place of insects in the animal kingdom? 



2. Give a comprehensive definition of an insect. 



3. Name the three parts of an insect's body. Does each part bear appendages? 



4. Name mouth parts of typical insects in order of their occurrence, beginning 



with the most anterior. 



5. Are they the same in all insects? 



6. What are the parts of an insect's leg? 



7. Are all of the legs alike in the grasshopper? 



8. Compare the legs of a caterpillar with those of a moth or butterfly, which 



produces the caterpillar. 



9. What is meant by a "pro-leg" or a "prop-leg"? 



10. What insects fly? Name a few which never fly. Do beetles fly? 



11. Give, in general, the life history of a butterfly. 



12. Of plant lice. 



13. Name the orders of insects and give example or examples under each order. 



14. Describe complete and incomplete metamorphosis in insects. Give 

 . examples. 



15. What is the difference between the pupal stage of a moth and that of a 



butterfly? 



16. How does an insect see, feel, smell, and hear? 



17. Name, in proper order, the divisions and sub-divisions used in classifying 



insects. 



