Experiments 



nest at twenty minutes to three. They had 

 therefore taken less than three-quarters of an 

 hour to cover the two miles and a half, a 

 very striking result, especially when we re- 

 member that the Bees did some foraging on 

 the road, as was proved by their bellies' yel- 

 low pollen, and that, on the other hand, the 

 travellers' flight must have been hindered by 

 the wind blowing against them. Three more 

 came home before my eyes, each with her 

 load of pollen, an outward and visible sign of 

 the work done on the journey. As It was 

 growing late, our observations had to cease. 

 When the sun goes down, the Mason-bees 

 leave the nest and take refuge somewhere or 

 other, perhaps under the tiles of the roofs, or 

 in little corners of the walls. I could not 

 reckon on the arrival of the others before 

 work was resumed, In the full sunshine. 



Next day, when the sun recalled the scat- 

 tered workers to the nest, I took a fresh cen- 

 sus of Bees with a white spot on the thorax. 

 My success exceeded all my hopes : I counted 

 fifteen, fifteen of the transported prisoners of 

 the day before, storing their cells or building 

 as though nothing out of the way had hap- 

 pened. The weather had become more and 

 53 



