64 The Hunting IVasps 



of the cell are not coated with any particular 

 cement ; but, in spite of their bareness, we can 

 see that they have been the object of the most 

 conscientious labour. The sand has been 

 heaped up and carefully levelled on the floor, 

 the ceiling and the sides, so as to prevent land- 

 slips and remove any roughness that might 

 hurt the delicate skin of the grub. Lastly, this 

 cell communicates with the passage by a 

 narrow entrance, just wide enough to admit the 

 Sphex laden with her prey. 



When this first cell is supplied with an ^^;^ 

 and the necessary provisions, the Sphex walls 

 up the entrance, but does not yet abandon 

 her burrow. A second cell is dug beside the 

 first and victualled in the same way ; then a 

 third and sometimes a fourth. Not till then 

 does the Sphex shoot back into the burrow all 

 the rubbish accumulated outside the door and 

 completely remove all the outward traces of 

 her work. Thus, to each burrow there are 

 usually three cells, rarely two and still more 

 rarely four. Now, as we ascertain when dis- 

 secting the insect, we can estimate the number 

 of eggs laid at about thirty, which brings up 

 to ten the number of burrows needed. On the 

 other hand, the operations are hardly begun 

 before September and are finished by the end of 

 the month. The Sphex, therefore, can devote 



