Bramble-bees and Others 



An inspection of a nest constructed under 

 these conditions is enough to convince us. It 

 now consists not of a string of chambers ob- 

 tained by simple transverse partitions, but of 

 a confused heap of clumsy many-sided com- 

 partments, standing back to back, with a tend- 

 ency to group themselves in storeys without 

 succeeding in doing so, because any regular 

 arrangement would mean that the ceilings pos- 

 sessed a span which it is not in the builder's 

 power to achieve. The edifice is not a geo- 

 metrical masterpiece; and it is even less satis- 

 factory from the point of view of economy. 

 In the previous constructions, the sides of the 

 reed supplied the greater part of the walls and 

 the work was limited to one partition for each 

 cell. Here, except at the actual periphery, 

 where the tube itself supplies a foundation, 

 everything has to be obtained by sheer build- 

 ing: the floor, the ceiling, the walls of the 

 many-sided compartment are all made of 

 mortar. The structure is almost as costly in 

 materials as that of the Chalicodoma or the 

 Pelopa^us. 



It must be pretty difficult, too, when one 

 thinks of its irregularity. Fitting as best she 

 can the projecting angles of the new cell into 



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