26o INSECT LIFE 



XIX 



far enough away, and came home by their local 

 knowledge. The experiment had to be tried again 

 at a greater distance, and from a point which the 

 Cerceris could not possibly know. 



I therefore took nine females from the colony 

 whence I had got them in the morning ; three of 

 these had been already experimented upon. Again 

 they were conveyed in a dark box — each imprisoned 

 in a paper twist. The starting-place was to be the 

 neighbouring town of Carpentras, about three kilo- 

 metres from the burrows. I meant to release them 

 not amid fields as before, but in a street in the midst 

 of a populous quarter, where the Cerceris, with their 

 rustic habits, had assuredly never penetrated. As 

 the hour was late I put off the experiment, and my 

 captives spent the night in their prison cells. 



The next morning, towards eight o'clock, I 

 marked them with a double white spot on the thorax 

 to distinguish them from those of the evening before, 

 which had only one, and set them free successively 

 in the middle of the street. Each mounted vertically, 

 as if to get as soon as possible from between the 

 houses and gain a wide horizon, then rising above 

 the roofs, instantly and energetically turned its flight 

 south. And it was from the south that I brought 

 them into the town, and their burrows are south. 

 Nine times with my nine prisoners did I obtain this 

 striking result — that an insect quite beyond its 

 bearings should not hesitate a moment what direction 

 to take to regain its nest. 



Some hours later I too was at the burrows. I 

 saw several of my yesterday's Cerceris with a white 

 dot, but none of the last set free. Had they been 



