ON STRUCTURE 



ALTHOUGH in the foregoing chapter a little has 

 been said on this subject, there is a great deal 

 more that a student should learn about the 

 general form of these creatures. 



They begin life as white or nearly colourless 

 grubs, which, after various changes of skin, 

 assume what is called the nymph or pupa stage, 

 during which a change occurs, believed to be 

 peculiar to the Hymenoptera; the fifth segment 

 of the larval body is transferred to the mass 

 which is called the thorax, so that a portion of 



hat looks like thorax is really the first segment 

 of the abdomen. Continental writers call this 

 portion sometimes the first abdominal segment 

 and sometimes the median segment, but New- 

 man gave it a definite name, the " propodeum", 

 and the most convenient method seems to be 

 to call it so, and treat it as a part of the thorax, 

 calling the first or basal segment of the abdomen 



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