The Mason-bees 



the scale at thirty-five pounds. Now the roof 

 whence it came was covered with similar 

 masses, adjoining one another, over a stretch 

 of some seventy tiles. Reckoning only half 

 the weight, so as to strike an average between 

 the largest and the smallest lumps, we find 

 the total weight of the Bee's masonry to 

 amount to three-quarters of a ton. And, 

 even so, people tell me that they have seen 

 this beaten elsewhere. Leave the Mason-bee 

 to her own devices, in the spot that suits her; 

 allow the work of many generations to accu- 

 mulate, and, one fine day, the roof will break 

 down under the extra burden. Let the nests 

 grow old ; let them fall to pieces when the 

 damp gets into them; and you will have 

 chunks tumbling on your head big enough to 

 crack your skull. There you see the work of 

 a very little-known insect.^ 



*The insect is so little known that I made a serious 

 mistake when treating of it in the first volume of these 

 Sowvenirs. Under my erroneous denomination of Chali- 

 codoma sicula are really comprised two species, one 

 building its nests in our dwellings and particularly under 

 the tiles of outhouses, the other building its nests on the 

 branches of shrubs. The first species has received vari- 

 ous names, which are, in order of priority: Chalicodoma 

 fyrenaica, Ler. {Megacliile) ; Chalicodoma pyrrhopeza, 

 Gerstacker; Chalicodoma rufitarsis, Giraud. It is a pity 

 78 



