Wonders of Insect Architecture. 



branch of a tree which has no lateral twigs, and makes 

 the branch the axis or central support of the nest. To 

 the branch a series of combs, each 

 composed of a limited number of 

 cells, are firmly attached, each tier 

 separated by an appreciable space. 

 Over these combs, to which it is 

 not attached, a very elaborate 

 paper envelope is formed, and 

 attached closely to the branch 

 above and below the combs, with 

 a small opening low down for 

 the entry and exit of the wasps. 

 The fibres of which this paper 

 envelope is formed are arranged 

 with wonderful regularity, and 

 the envelope is tinted with longi- 

 tudinal bands of different colour, 

 while its surface is marked with 

 transverse oval ridges, giving it 

 a scalloped appearance. 



The slim-bodied Polybias of 

 tropical America are all remark- 

 able builders. Some, like the 

 Polybia liliacea, make a wonder- 

 ful nest, nearly four feet in height 

 and containing thousands of cells, 

 which is attached to a branch of 

 a tree and covered with a thick, Nest of Polybia. 

 rough envelope of almost cardboard texture. Others make 

 the most tiny, frail, and beautifully formed habitations, 

 about a quarter of an inch in length, on the under sur- 



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