HYMENOPTERA. 

 CHARACTERISTICS. 



I. Four membranous wings, bare of scales. 



Bees. 



Body thick-hairy. 



Legs usually thickly clothed with hairs. 



Wasps. 



Body smooth, constricted at front of abdomen, 

 or pedunculate. 



Ants. 



Body smooth, not pedunculate, but one of the 

 abdominal segments is expanded to form a 

 scale or button-like knot next to the thorax. 



Ichneumon flies. 



Abdomen curved and, in some of the smaller 

 ichneumons, pedunculate. 



Thalessa has three long hairs (they may look 

 as if they were one) at the end of the abdomen. 



SawQies. 



Head and thorax wide where they join Ihe 

 abdomen ; the female bears a saw-like organ at 

 the end of the abdomen. 



Homtails. 



Head and thorax wide, and abdomen broad and 

 usually cylindrical; abdomen bears a spine- 

 like organ; insects large. 



Gallflies. 



Abdomen compressed and pedunculate by the 

 first abdominal segment; the second and third 

 abdominal segments much larger than the 

 other segments ; insects small. 



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