260 



HOMES WITHOUT HANDS. 



each structure appearing to be capable of unlimited enlargement. 

 The mode by which the wasps increase the size of their pensile 

 home is equally simple and efficacious. When the number of 

 the inhabitants becomes so large that a fresh series of cells is 

 required, the insects enlarge their home with perfect ease, and at 

 the same time without destroying its symmetry, a point which is 



CHAUTtKGUS XIDUL.VNS, 



often forgotten wlien human architects undertake the enlarge- 

 ment of some fine old edifice. Taking the bottom of the nest as 

 the starting-point, they build upon it a series of cells, taking 

 care to add another row or two to the circumference, so as to 

 increase the diameter in proportion to the length. They then 

 add fresh material to the outer wall, which is lengthened so as 

 to include the new tier of cells, and then the bottom is closed 

 with a new floor, which in its turn will become the ceiling of the 

 next tier of cells. 



These nests are therefore permanent ; unlike the habitations 

 of the common British wasps, which are only used for a single 

 season and then deserted, the few surviving females seeking their 

 winter quarters elsewhere, and always choosing some fresh spot 

 for the nucleus of a fresh colony. On the average, a well-sized 



