Bramble-bees and Others 



cal wafers. For this work of fortification, 

 artistic refinement seems superfluous; at any 

 rate, the pieces of leaves are for the most 

 part irregular. You can see that the insect 

 has cut them out hurriedly, unmethodically 

 and on a different pattern from that of the 

 pieces intended for the cells. 



I am struck with another detail in the bar- 

 ricade. Its constituents are taken from stout, 

 thick, strong-veined leaves. I recognize 

 young vine-leaves, pale-coloured and velvety; 

 the leaves of the whitish rock-rose {Cistiis 

 albidus) ^ lined with a hairy felt; those of the 

 holm-oak, selected among the young and 

 bristly ones; those of the hawthorn, smooth, 

 but tough; those of the cultivated reed, the 

 only one of the Monocotyledones exploited, 

 as far as I know, by the Megachiles. In the 

 construction of cells, on the other hand, I see 

 smooth leaves predominating, notably those 

 of the wild briar and of the common acacia, 

 the robinia. It would appear, therefore, that 

 the insect distinguishes between two kinds of 

 materials, without being an absolute purist 

 and sternly excluding any sort of blending. 

 The very much indented leaves, whose pro- 

 jections can be completely removed with a dex- 



244 



