MINING-BEES. 37 



performed by the female. The females of the solitary bees 

 have no assistance in their tasks. The males are idle ; and 

 the females are unprovided with labourers, such as the 

 queens of the hive command. 



Keaumur mentions that the bees of this sort, whose 

 operations he had observed, piled up at the entrance of 

 their galleries the earth which they had scooped out from 

 the interior ; and when the grub was hatched, and pro- 

 jDcrly provided with food, the earth was again employed 

 to close up the passage, in order to prevent the intrusion 

 of ants, ichneumon-flies, or other depredators. In those 

 which we have observed, this was not the case ; but 

 every species differs from another in some little pecu- 

 liarity, though they agree in the general principles of 

 their operations. 



