INSECTS DIAGRAM 6 



105 



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Gnat magnified. 



time that they emerge from the egg to their first metamorphosis 

 is the larva state ; that which separates the first metamorphosis 

 from the second, is the pupa, nymph, or chrysalis state ; and the 

 third state is that of the imago OY perfect insect. 



Larva state. In this state, insects have often the form of a 



worm, and this name is applied 

 to them ; the larvpo of butter- 

 flies are caterpillars ; the 

 white worm will become a cock- 

 chafer ; the maggot will become 

 a flesh fly ; and thus with a num- 

 ber of insects. 



The habits of larva) often 

 differ much from those of the 

 perfect insect which proceeds 

 from them. In the first place 

 lavse never fly. There are many 

 larvso which live in water while the 

 perfect insect is aerial : this is the case, 

 for instance, with the gnats. Other 

 larvse live underground, like the white 

 worm, while the cockchafer lives in 

 trees ; larvso do nothing but eat for 

 almost all their lives, and the greater part are therefore injurious 

 to man. Larva) have a very variable number of legs, sometimes 

 none at all, like maggots. Lastly, they have frequent moults 

 according to their growth. 



Many larva) spin a cocoon like the silkworm, in which they 

 enclose themselves to undergo their first metamorphosis. 



Pupa or chrysalis state. This state is that in which the eilk- 

 worm is found in the co'coon when it 

 is opened before the moth emerges. 

 The silkworm is contracted together ; 

 it is generally of a brown colour, and 

 it moves the rings of the hind part 

 Chrysalis. of its body which terminates in a 



Larva of gnat magnified. 



