108 BEES AND WASPS [OH. 



favourable variations to offspring, for they produce 

 none. As a study in evolution and heredity this 

 question is full of interest. 



CHAPTER VIII 



SOME STRUCTURAL FEATURES: THE STING AND 



THE "TONGUE" 



IT will not be out of place to include a description 

 of the weapon by which the bees, wasps and ants are 

 distinguished from other insects, and of the "tongue" 

 which plays so important a part in the economy and 

 on whose characters the primary classification of the 

 bees is based. 



Strictly speaking, the sting belongs to the female 

 reproductive system, and corresponds to an ovi- 

 positor : but unlike the ovipositor of many of the 

 lower Hymenoptera (saw-flies, etc.), it does not project 

 from the body, but is withdrawn within it ; it has more- 

 over lost all direct connexion with oviposition, the eggs 

 escaping at its base instead of passing through it. 

 If a living worker or "queen" wasp be held in a pair 

 of forceps, the insect will be seen repeatedly to dart 

 out from the apex of the abdomen a sharply pointed 

 structure which is usually mistaken for the sting. 

 This organ, though sharp and strong enough to pene- 

 trate the skin is not, however, the true sting by which 



