AMMOPHILA AND HER CATERPILLARS 



stinging agree fairly well with those of Fabre ; but there 

 is one important exception. In his cases the middle seg- 

 ments, upon one of which the egg is laid in our species 

 as well as in his, were in- 

 variably stung, and this he 

 considers a point of extreme 

 importance. In one of our 

 cases the middle segments 



Were not touched. CATERPILLAR WITH EGG OF 



AMMOPHILA URNARIA 



The point in which our 



observations differ most widely from those of Fabre is 

 in the condition of the caterpillars after the stinging. 

 He seems to have found that they always lived a long 

 time, but in a motionless or nearly motionless state ; 

 and he dwells at length upon the necessity of both of 

 these conditions, since he believes that while the wasp 

 larva must have perfectly fresh food, any violent mo- 

 tion would imperil its safety. As a matter of fact we 

 found a wide variation in the thoroughness with which 

 the wasps performed their task. We had, in all, fifteen 

 caterpillars upon which urnaria had worked her will ; 

 and while a few of them fulfilled to a nicety the con- 

 ditions which Fabre believes to be imperative, most of 

 them were far from doing so. Some of them lived only 

 three days, others a little longer, while still others showed 



29 



