THE DIODONTI. 101 



these off it prevented them from returning and scenting the 

 trail to communicate the intelligence to others." 



With our wasps there was no such struggle as this for the 

 possession of the aphides. They made no resistance and we 

 never saw them try to strike the ants from the bushes. "We 

 have been especially interested in Mr. Belt's opinion that some 

 wasps are much cleverer than others as we have again and again 

 noted the same thing. 



We found that when a wasp secured an aphis she flew with 

 it to another leaf near by, alighting, this time, on the upper 

 surface. She then passed it back from her mandibles to the 

 second pair of legs, and holding it, with them, under her body, 

 she proceeded to make use of the first pair in giving herself a 

 thorough cleaning. Her face, especially, was well washed and 

 rubbed. We afterward saw other wasps put themselves in 

 order and smooth their ruffled plumage after catching their 

 prey. Ammophila was especially given to making her toilet 

 on these occasions, but she had some excuse for it since she 

 could not subdue her victim without going through something 

 of a struggle. With Diodontus the performance became 

 absurd, since the capture of the aphis required no combat, 

 scarcely, indeed, an effort. The victim was merely picked up 

 and carried off. 



Her dainty person being put to rights, our little wasp brought 

 the aphis forward, and squeezed its neck repeatedly between her 

 mandibles. With Diodontus this malaxation is always accom- 

 plished delicately, so that the skin is not broken, but there is a 

 considerable variation in the thoroughness of the work. In 

 most cases the aphides are killed, since we afterward found that 

 they were almost invariably dead in the nests, even in those that 

 were freshly provisioned. In other cases the disturbance was 

 so slight that they were able to walk about as soon as they 

 were released, seeming to be scarcely injured. 



To see the whole process more conveniently we repeatedly 

 caught a wasp and placed her in a bottle with a leaf upon 

 which were aphides. Using a glass, we could then see what 



