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TEXT-BOOK OF ENTOMOLOGY 



In what may be termed the 3d stage (Fig. 616, C), though the 

 distinction is a very arbitrary one, the change is accompanied by a 

 moulting of the skin, and a great advance has been made towards 

 assuming the pupal form. The abdomen is very distinctly separated 

 from the thorax, the propodeum being closely united with the thorax, 

 and the head and thorax taken together are nearly as large as the 

 abdomen, the latter now being shorter and perceptibly changed in 



form, more like that of the completed pupa, while there are other 

 most important changes in the elaboration of the parts of the thorax, 

 particularly the tergites, and of the head and its appendages, ^lean- 

 while the ovipositor has been completed and nearly withdrawn 

 within the end of the abdomen. 



The next to study the transformations of the Hymenoptera was 

 Ganin, who discovered the early remarkable pre-eruciform larva\ as 



