300 The Httnthig Wasps 



in the box. I opened it and found my prisoner 

 engaged in scraping the cardboard wall with 

 its mandibles, while its body was half outside 

 the sack. The cardboard had already suffered 

 considerably and a heap of tiny fragments were 

 piled in front of the opening of the hammock, to 

 be used later. For lack of other materials, the 

 grub would doubtless have employed these 

 scrapings for its building. I thought it better 

 to provide something in accordance with its 

 tastes and to give it sand. Never had Bcmbex- 

 larva built with such sumptuous materials. I 

 poured before the captive sand from my ink- 

 stand : blotting-sand, blue sand sprinkled with 

 little gilt mica spangles. 



This supply is placed in front of the mouth of 

 the bag. The bag itself is in a horizontal posi- 

 tion, which is convenient for the coming task. 

 The larva, leaning half out of the hammock, 

 picks up its sand almost grain by grain, rum- 

 maging in the heap with its mandibles. If any 

 grain is found to be too bulky, the grub takes it 

 and throws it away. When the sand is thus 

 sorted, the larva introduces a certain quantity 

 into the silken edifice by sweeping it with its 

 mouth. This done, it retires into the eel-trap 

 and begins to spread the materials in a uniform 

 layer on the lower surface of the sack ; then it 

 gums the different grains and inlays them in the 



