98 



Insect Architecture. 



found a nest of this description attached to the stem of a 

 nettle. Reaumur says that they are sometimes attached to 

 the branch of a thorn or other shrub, or to stalks of grass ; 

 peculiarities which prove that there are several species of 

 these wasps. 



The most remarkable circumstance in the architecture 

 of this species of vespiary is, that it is not horizontal, like 

 those formerly described, but nearly vertical. The reason 

 appears to be, that if it had been horizontal, the cells must 

 have been frequently filled with rain , whereas, in the position 

 in which it is placed, the rain runs off without lodging. It 

 is, besides, invariably placed so as to face the north or the 



Wasps' Cells attached to a Branch. 



east, and consequently is less exposed to rains, which most 

 frequently come with southerly or westerly winds. It is 

 another remarkable peculiarity, that, unlike the nests of 

 other wasps, it is covered with a shining coat of varnish, to 

 prevent moisture from soaking into the texture of the wasp's 

 paper. The laying on this varnish, indeed, forms a con- 

 siderable portion of the labour of the colony, and individuals 



