The Mason-Wasps 



sand to make the entrance of the hole per- 

 ceptible and to have laid the foundation of 

 the tube. 



" But the work can proceed quickly only 

 so long as the Wasp is able to moisten the 

 sand. She is obliged to take trouble to re- 

 new her store of water. I do not know 

 whether she simply went to take in water at 

 some stream, or whether she drew, from 

 some plant or fruit, a more sticky fluid; 

 what I do know is that she returned without 

 delay and set to work with renewed zeal. 

 I observed one Wasp who managed, in 

 about an hour, to sink a hole the length of 

 her body and who raised a chimney as tall 

 as the hole was deep. At the end of a few 

 hours the tube stood two inches high and 

 she was still deepening the hole that lay un- 

 derneath. 



" It did not appear to me that she had 

 any rule respecting the depth which she 

 gives it. I have found some whose hole 

 ran more than four inches from the orifice; 

 others whose hole measured only two or 

 three inches. Again, over one hole you 

 will find a tube twice or three times as long 

 as that over another. Not all the mortar 

 removed from the hole is invariably em- 

 ployed to prolong it. In cases where the 

 40 



