5Cu HABITATIONS OJ INSECife. 



iition walls being double''. These cells, which, as wa^ps 

 do not store up any food, serve merely as the habita- 

 tions of their young, are not, like those of the honey- 

 bee, arranged in two opposite layers, but in one only, 

 their entrance being always downwards: consequently 

 the upper part of the comb, composed of the bases of 

 the cells, which are not pyramidal but slightly convex, 

 forms a nearly level floor, on which the inhabitants can 

 conveniently pass and repass, spaces of about half an 

 inch high being left between each comb. Altliough the 

 combs are fixed to the sides of the nest, they would not 

 be sufficiently strong without further support. The 

 ingenious builders, therefore, connect each comb to 

 that below it by a number of strong cylindrical columns 

 or pillars, having according to the rules of architecture 

 their base and capital wider than the shaft, and com- 

 posed of the sau^e paper-like material used in Other 

 parts of the nest, but of a more compact substance. 

 The middle combs are connected by a rustic colonnade 

 of from forty to fifty of these pillars ; the upper and 

 lower combs by a smaller number. 



The ceils, which in a populous nest are not fewer 

 than iG,000, are of different sizes, corresponding to 

 that of the three orders of indi^ iduals which compose 

 the community ; the largest for the grubs of females, 

 the sm.allest for those of workers. The last al^vay* 

 occupy an entire comb, while the cells of the males 

 and females are often intermixed. — Besides openings 

 which are left between tlie walls of the combs to admit 

 of access from one to the otiier, there are at the bottom 



' Memoirs of the Wernsrian Society, ii. 260. 



