The Mason-Wasps 



six captures belong to the Nest-building 

 Odynerus and all the six are females. 

 Any one passionately interested in a pro- 

 blem and suddenly discovering the data re- 

 quired for its solution will understand my 

 emotion. The joy of the moment has its 

 anxious side: who knows what turn things 

 will take between the huntress and the 

 quarry? I shift an Odynerus and a Chry- 

 somela-larva into a bell-glass. To stimu- 

 late the assassin's ardour, I set the glass 

 cage in the sun. Here is the story of the 

 drama, told in detail. 



For a good quarter of an hour, the cap- 

 tive clambers up the sides of the bell-glass, 

 crawls down again and up again, seeking an 

 outlet whereby to escape, and seems to pay 

 no attention to the game. I was already 

 despairing of success when suddenly the 

 huntress falls upon the larva, turns it over, 

 belly upwards, clasps it and stings it thrice 

 in succession in the thorax, particularly un- 

 der the neck, in the median region, a point 

 at which the sting is more insistent than 

 elsewhere. The close-clasped larva does its 

 utmost to protest, emptying its scent-bottles 

 and oiling itself with petrol; but these de- 

 fensive tactics have no effect. Indifferent to 

 the heady perfume, the Odynerus performs 



210 



