Larval Dimorphism 



flight, Its long investigations and its sudden 

 blows with the tip of its belly against the layer 

 of earth. The Bombylii^ observe similar 

 tactics when soaring at a short height above 

 the ground. 



I at once rushed to the spot touched, lens in 

 hand, in the hope of finding the egg which 

 everything told me was laid during that tap 

 of the abdomen. I could distinguish nothing, 

 In spite of the closest attention. It is true that 

 my exhaustion, together with the blinding 

 light and scorching heat, made examination 

 very difficult. Afterwards, when I made the 

 acquaintance of the tiny, thing that issues from 

 that egg, my failure no longer surprised me. 

 In the leisure of my study, with my eyes rested 

 and with my most powerful glasses held in a 

 hand no longer shaking with excitement and 

 fatigue, I have the very greatest difficulty 

 in finding the infinitesimal creature, though I 

 know exactly where it lies. Then how could 

 I see the egg, worn out as I was under the 

 sun-baked cliff, how discover the precise spot 

 of a laying performed in a moment by an in- 

 sect seen only at a distance? In the painful 

 conditions wherein I found myself, failure 

 was inevitable. 



'Bee-flies. — Translator's Note. 

 9X 



