366 



THE INSECT WORLD. 



hiding-place to find the road before it free. The Xylocopce pass the 

 winter in the pupa state, and the perfect insects, with wings of a 

 beautiful metallic violet, appear in the spring, but are not found in 

 Great Britain (Fig. 339). 



Other solitary bees have their hind legs unsuited for the gathering 



' Fig. 342. — Rose Megachile {Megachile centuncularis). 



of pollen, but have the rings of the abdomen furnished with hairs for 

 that purpose. Such are the Mason Bees of Reaumur, belonging to 

 the genera Osmia and Chaiicodoma,''' which build their nests against 

 walls with tempered earth, which become very hard. 



* At a meeting of the Entomological Society of London, Feb. i8th, 1867, Mr. 

 Newman exhibited the lock of a door, one of several which in 1866 were found at 

 the Kent Waterworks, Deptford, to be completely filled and choked up wiih nestS 

 of Osmia Bicornis: a portion of the nest had been forced out by the insertion of the 



