riiylctic Parallelism in Mctamorphic Species. 48 1 



III. 



INCONGRUENCES IN OTHER ORDERS OF INSECTS. 



ALTHOUGH the order Lepidoptera is for many 

 reasons especially favourable for an investigation 

 such as that undertaken in the previous section, it 

 will nevertheless be advantageous to inquire into 

 the form-relationships of the two chief stages in 

 some other orders of metamorphic insects, and to 

 investigate whether in these cases the formation 

 of systematic groups also coincides with common 

 conditions of life. 



HYMENOPTERA. 



In this order there cannot be the least doubt as 

 to the form-relationship of the imagines. The 

 .characteristic combination of the pro- and meso- 

 thorax, the number and venation of the wings, and 

 the mouth-organs formed for biting and licking, are 

 found throughout the whole order, and leave no 

 doubt that the Hymenoptera are well based on 

 their imaginal characters. 



But it is quite different with the larvae. It may 

 be boldy asserted that the order would never 

 have been founded if the larvae only had been 



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