THE MASONS 217 



and try — in vain — to remove all traces 

 of their presence. 



All the mud nests are very friable and 

 easily broken, so that it is difficult to re- 

 move a cluster of them without destroying 

 some. The mud of the nests does not 

 seem to be glued together with secretion 

 from the wasp's mouth, at least not as a 

 rule, but merely dries, and thus keeps its 

 form. It is moulded solidly, so that when 

 dry it is strong enough for the purpose 

 unless it happens to be placed where, 

 through some accident, the rain wets it, 

 in which event it quickly falls to pieces. 



In taking down the cells in the little 

 shed the lower tier was broken, and a 

 larva left exposed in one cell, while a pupa 

 in its shell was exposed in another. The 

 anxious mother, returning to finish her 

 last cell and finding the whole fabric gone, 

 with only these luckless infants left and 

 exposed to a merciless world, at once set 

 to work plastering them up again. Evi- 



