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often complicated changes take place during and after a 

 period of growth. The phases in the life of an insect 

 are, first the egg stage, second the larva or caterpillar, 

 third the pupa or chrysalis, and fourth the sexual adult. 

 The changes in the egg, so-called embryonic changes 

 need not concern us. The larval stage is the period of 

 growth, the period of ravenous feeding, the time during 

 which the majority of insect enemies of the Rose are so 

 harmful. The caterpillar on leaving the egg shell is 

 very small. It gradually grows until its skin is too 

 small to contain the body contents. The skin then splits 

 and the insect crawls forth from the old skin with a new 

 one ready formed beneath, soft in texture and capable of 

 expanding. This process of casting the skin is known 

 as " Ecdysis." Several of these moults take place in 

 the larval stage. Preceding, during, and just after the 

 moult, the larva does not feed, and moreover is sluggish 

 and tender. At this time it is often more easily killed 

 by insecticides than at others ( = freshly moulted green 

 fly and leaf-hoppers). 



At last the larva reaches maturity and then casts its 

 skin for the last time and enters the third phase of life, 

 the pupa or chrysalis. Previous to so doing, the larva 

 either spins a cocoon of silk, attaches itself at its tail end 

 to some object by silk, or enters the soil and forms a case 

 of earth in which the pupal stage is found ; a few pupae 

 are found nude in the soil, others in wood and seed. 



This pupal stage is the period of metamorphosis or 

 transformation. The pupa proper is incapable of any- 

 great movement, nor does it take food. It is the period 

 when the greater part of the caterpillar's organisation is 

 destroyed and remodelled into the adult. 



