EYMENOPTERA (BEES, WASPS, ANTS.) 



Bees, wasps, and ants are the better known represen- 

 tatives of this group, all the members of which agree in 

 having four membranous wings (the front pair the larger) 

 with comparatively few cross-veins. The mouth-parts are 

 fitted both for biting and for sucking. There is a com- 

 plete metamorphosis. So far as we can judge, these are the 

 most intelligent of all insects, and the student who investi- 

 gates their habits is continually rewarded by new facts, 

 which show that their small brains are most highly devel- 

 oped. In other points of structure, however, they are 

 much less complicated. 



In the lower forms the female is provided with an ovi- 

 positor, frequently of great length, which is well adapted 

 for boring. In the higher this ovipositor is modified into 

 a sting a weapon of offence and defence, the efficiency of 

 which is increased by an associated poison-gland. 



The lowest forms are the sawflies, the larvae of which are 

 vegetable-feeders, some eating the leaves of plants, others 

 boring in the solid wood. A little higher in the scale come 

 the gall-flies, those forms which lay their eggs in various 

 plants and in some way so stimulate the vegetable tissue 

 that strange growths galls are formed. Allied to these 

 last are the ichneumon-flies, which lay their eggs in other 

 insects. Here the larvae hatch out, feed upon the host, 

 at last destroying it. Then pupation comes, and the per- 

 fect insect emerges to repeat the process. Naturally these 

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