532 COMPARATIVE ANATOMY AND PHYSIOLOGY. 



developed egg has a more or less worm-like shape ; it 

 may be headless and legless (maggot), or have a 

 head, but 110 legs (grub), or be provided with head, 



Fig. 218. A, Larva ; B, Chrysalis ; c, Imago of Papilio machaon. 



legs, and fore-legs (caterpillar). The larva grows, 

 and moults its skin as it grows ; after a time it ceases 

 from this active mode of life, and passes into a more 

 quiescent condition, as in the case of the butterfly, or, 



