INSECTS. 



91 



(Fig. 62, left), and fully developed wings are only 

 present after the last moult. The ovipositors of 

 female insects, in those cases where the metamorphosis 

 is incomplete, first appear as fulty developed organs 

 in the perfect condition of the animal, but begin to 

 develop in the preceding stage. In eases of this kind 

 of metamorphosis the young insect ("larva") closely 

 resembles the adult in form even in the first stage 

 of development. In insects undergoing complete 

 metamorphosis the difference between larva and adult 

 insect (imago) is much greater (Figs. 60, 61, 65). 



Fig. 65. — The CommoQ Cockchafer (^Meloloniha vulgaris). 

 Larva, pupa, female flying, and male creeping out of the earth. 



The time passed in the pupa state by insects with 

 complete metamorphosis is by no means always of 

 the same length. For example, there are two genera- 

 tions annually of the cabbage white butterfly ; one 

 lives through the winter in the pupa state, the pupse 

 of the other are found in summer. So that while an 

 insect of the winter generation lives about half a year 

 in the pupa state, this condition lasts only about a 

 month in the summer generation. A higher tempera- 

 ture hastens the development. 



Although the insect in the pupa state takes no 



