PLASTERERS 



never more the builder is particular about that, and seems 

 to regard it as a most important ceremony. 



This piece of rustic architecture can defy the worst of 

 weather; you can make no impression on it with your 

 fingers, nor can you remove it unbroken with a pocket-knife. 

 Its peculiar form and the fragments of grit which stick out 

 on all sides recall certain ancient cromlechs and tumuli dotted 

 over with gigantic blocks of stone. 



Such is the appearance of a single, isolated cell. In most 

 cases, however, the wasp constructs others on the top of this, 

 to the number of five or six or even more, and so saves a 

 certain amount of labour, because where two chambers are 

 side by side the same wall serves for both of them. But the 

 graceful shape is lost, and at the first glance such a group 

 looks like nothing more than a splash of mud covered all 

 over with tiny stones. If, however, we examine this ap- 

 parently shapeless mass more closely, we can distinguish the 

 number of chambers by the bell-shaped openings, each one 

 being quite distinct from all the others and furnished with 

 its little stone door embedded in cement. 



Quite at the beginning of the springtime you may observe, 

 foraging among the flowers, some pretty little hymenoptera 

 whose coppery skin is covered with bright red down. These 

 are the Osmia bees, and their arrival, like that of the 

 swallows, foretells the advent of sunny days. 



In spite of their dainty appearance they are sturdy 

 labourers accustomed to hard work, and they pass no small 

 portion of their lives in making mortar from mud. Unlike 

 many of their relatives, these insects are merely plasterers. 

 They are not even skilled in the manufacture of hydraulic 

 cements from road-dust and saliva, but are content to build 

 their nests of no better material than ordinary mud, 

 collected and moulded, apparently, without any special 



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