LIST OF ILLUSTRATIONS. 



1. Skull of a grasshopper . 4 



2. Portion of compound eye of a fly ....... 8 



3. Median ocellus of a honey bee . 9 



4. Antenna of a carrion beetle . . . . 12 



5. Tactile hair 14 



6. Nerve endings in tip of labial palpus of a fish moth . 1 6 



7. Ear of a grasshopper . . . . . ; . . . . . . . 17 



8. Locust from lateral aspect, auditory organ ... 18 



9. Auditory hairs of a mosquito ......... 18 



10. Antenna of a mosquito . * . . . . ... . . 19 



1 1 . Tracheal system of an insect . . ... . . . . . 21 



12. Tracheal gill of a Mayfly ......-. 22 



13. Digestive system of a beetle .......... 25 



14. Stages in development of nervous system of a 

 dipter water beetle . .' . . .... 29 



15. Concentration in nervous system of a dipter . . 30 



1 6. Hypermetamorphosis of Epicauta cinerea . . ... . 34 



17. Larva of tomato worm .... . ....... 35 



18. Pupa of tomato worm .... . ' . ' : . '. .-. . . 36 



19. Adult of tomato worm ..,'...-,..... 37 



20. Development of squash bug .......... 41 



21. Diagram of insect net 1 .... 49 



22. Dip net ..................... 50 



23. Drying board 55 



24. Great water scavenger ..'... 61 



25. Egg case of water scavenger . . . . _ . . . . 61 



26. Larva of water scavenger 62 



27. A flower beetle, Euphoria inda 62 



28. Some California ladybird beetles 70 



29. The searcher 71 



ix 



