362 WASP STUDIES AFIELD 



Under the next heading we come to the expression of 

 emotions in these wasps. It is exceedingly difficult, in wit- 

 nessing demonstrations like the following to think of these 

 creatures as mere automata or mechanical instruments. 



In the sun-dance of Bembix nubilipennis, sufficient emo- 

 tion is displayed when the dancing males leave their aerial 

 flight and masses of them struggle on the ground to gain 

 possession of the female and then pursue the mated pair 

 on the wing until they overtake them and form the teeming 

 mass again. 



Pompiloides tropicus, upon regaining her spider after a 

 long search, pounced upon it with unmistakable viciousness. 

 Later, when some ants came near to her burrow she bit at 

 them, kicked at them angrily and curled up her sting at 

 them menacingly until they withdrew, either of their own 

 accord or in consequence of her threats. 



Pompiloides mavginatus displayed decided agitation 

 when she came to a spider's turret, lingered about it for 

 some time in vain, then violently rammed her head against 

 the turret. 



If wasps are capable of the expression of the emotion 

 of anger, Pseudagenia pulchripennis certainly made the 

 display when the spider which she was pursuing gave one 

 leap and escaped. The wasp became frantic; the sight of 

 the spider and the fact that she had been fooled so excited 

 her that she acted madly, walking, flying, running about 

 the ground in indescribable directions until she tumbled 

 headlong into a mole's hole. The play of Trypoxylon 

 clavatum might probably be classified as the expression of 

 some emotion or other. 



Stizus unicinctus, after examining near a dozen spots of 

 broken soil, arrived at a certain inconspicuous pile of loose 

 earth. Instantly her manner changed when she had "struck 

 pay dirt"; she became greatly excited, nervous, quivering 



