CHAPTER VIII 



MOSQUITOES AND CATERPILLARS 



In the following* studies of insect life-histories the growth 

 and development of the insects from hatching to maturity 

 can be readily observed in the schoolroom. The particular 

 insects chosen are selected because they can be easily ob- 

 tained and reared indoors, and because they present especially 

 interesting changes in their development. But other insect 

 life-histories may be observed, either completely or in part, 

 if it is so desired. Various caterpillars and chrysalids can 

 be kept alive and watched as they develop into moths or 

 butterflies, and various grubs that live in the ground can be 

 kept until they become beetles. Flesh-flies may be allowed 

 to lay their eggs on decaying meat, and the hatching of the 

 maggots, their change into brown seed-like pupae, and 

 the final emergence from these of the blue and green flies 

 all carefully noted. 



MOSQUITOES 



The eggs and hatching. — Mosquitoes' eggs are usually 

 laid in small blackish masses, which float on the surface 

 of water. (In the case of some species the eggs are laid 

 in groups of only a few, or even deposited singly.) These 

 sooty egg-masses are composed of a single layer of slender 

 elongate eggs standing on end and loosely fastened to- 



*Most of the work outlined in this chapter, as also that of the succeeding 

 chapter, can be done only in the spring or summer, so that this part of the 

 book although devoted to a subject which should logically be treated imme- 

 diately after, — if indeed not before — the structure and general physiology, 

 may be postponed until after the next part (classification) is studied. 



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