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CALIFORNIA STATE COMMISSION OP HORTICULTURE. 



The other group, which have an "indirect" or complete metamor- 

 phosis, are grouped together as Heterametabola. In these, the insects 

 pass through the regular stages: the egg, the growing larva, the pupa, 

 and the perfect insect or imago. 



FIG. 3f>. Six successive instars of tin- squash-bug (Anasa trixti*). 



In the pupal stage of most insects having an indirect or complete 

 metamorphosis, there is a strong approach to suspended animation, for 

 while the pupa will sometimes squirm, when touched, it usually 

 remains in perfect rest until the great change has been accomplished. 



B 



FIG. 36. Papilio troilus. A, larva ; B, larva suspended for pupation ; 

 C, chrysalis. Natural size. 



In those insects which have a direct metamorphosis, the insect in its 

 transition stage is spoken of as a nymph. 



The changing insect in other cases is known as a pupa, although in 

 the case of butterflies it is often referred to as a chrysalis. 



