10 THE SOLITARY BEES 



numbers on the lawn under notice and so passed 

 unrecognized. They may safely be left alone, 

 as they never seem to breed many consecutive 

 years in one such locality : probably the treat- 

 ment of a lawn does not suit them, mowing and 

 rolling upsetting their arrangements. We will 

 now consider these arrangements. The female bee, 

 so soon as she realizes that she is charged with 

 the duty of providing for her future offspring, 

 makes a burrow in the ground, and the earth 

 thrown up from the tunnel forms the little heap 

 which is so observable ; this burrow varies in depth 

 from 6 to 12 inches and has short lateral branches ; 

 each of these she shapes, more or less, into the 

 form of a cell, provisions it with a small mass 

 of pollen mixed with honey for the maintenance 

 of the larva when hatched, and lays her egg ; she 

 then seals up that cell and proceeds to the next, 

 and in this way fills the burrow up until pretty 

 near the surface. The bee caterpillar when 

 hatched is a white grub-like creature which, 

 after devouring the food provided for it, becomes 

 more or less torpid ; it then makes its final 

 change of skin, after how long a period is probably 

 uncertain, and appears in the nymph stage. 



