THE BURROWS OF BEES 283 



the tube is full. The leaf-cutting bees line their 

 earthen nests with a layer of leaf-discs and construct 

 thimble-shaped leafy cells in which to store their 

 pollen and lay their eggs. The carder-bees drape 

 some ready chink with wool or cotton which they gather 

 from plants near by. In these various ways they 

 lay and feed their young, and defend them against 

 mould that most insidious and deadly of their 

 enemies. 



Mouldiness is, however, not the only foe the bees 



FIG. 59. Burrow of the Leaf-cutter Bee (Megachile centuncularis}. 

 (From a specimen in the Manchester Museum.} 



have to fear. Another and more widespread enemy 

 is ever ready to annex their ingatherings. The ten- 

 dency to take what others have gathered and to divert 

 the store for their own ends exists in all capable 

 organisms, and amongst bees there is a whole tribe of 

 cuckoos who plant their eggs in others' nests. Even 

 those steady workers, the mason-bees, will, if inter- 

 rupted, carry their provisions to a neighbouring, 

 completed cell, and there strive to gain a footing, 

 and many other solitary bees, if delayed or unable to 

 finish their tale of cells, will tear what they have done 



