Insects. 5171 



assume the perfect hexagon, whilst in the centre of the comb 

 the four or five foundation cells, or those formed at the commencement, 

 are carried upwards in perfect hexagonal forms, the outer walls having 

 the angles of the hexagon, as acute and regular as those which come 

 in contact with the angles of adjacent cells. 



We must now cany our mind backwards to the point at which we 

 traced the formation of the footstalk which supports the nest from the 

 roof of the chamber : at the same time that the mother wasp constructs 

 the foundation of the first four or five cells she simultaneously spreads 

 over them a detached covering, exactly represented by an opened 

 umbrella : this covering serves to carry off any wet which might drop 

 from the roof of the chamber, and prevents any particles of dirt from 

 falling on the top of the comb, wasps never allowing any particles of 

 dirt or rubbish to litter their dwellings. As the comb widens, so the 

 labour of increasing the outer envelope proceeds, not in a single sheet, 

 but additional layers are spread over that which at first served to 

 shelter the foundation-cells ; by degrees the nest assumes the exact 

 resemblance of a half-blown rose, the successive layers of delicate 

 papery tissue representing in form the petals of the flower. 



The materials of which the nests of wasps are constructed are well 

 known to be the scrapings of different kinds of wood, mixed up into a 

 plastic consistency with a liquid or gluten secreted by the wasp; this 

 she spreads out as required with her broad flattened tongue, and for 

 the purpose of collecting the wood scrapings she is furnished with 

 stout denticulated jaws. Great differences will be observed in the 

 nests of wasps obtained in different localities ; in some places I have 

 observed nests nearly white, sometimes they are of a gray colour, 

 whilst in another locality they are of a rich variegated brown and 

 yellow. The differences of colour are attributable to the different 

 kinds of wood which prevail in a district, but this only in a degree : 

 it is to the situation in which the nest is found that we must princi- 

 pally look for the cause of the difference. Wasps, as well as many 

 other Hymenopterous insects, exhibit on all occasions a power and 

 will to reason and to act according to circumstances : in intelligence 

 they are far removed from the creatures of blind instinct which some 

 have supposed them to be. If a wasp, Vespa vulgaris, for instance, 

 builds her nest under ground, it is necessary that the materials she 

 uses should be very different from those which would suffice were she to 

 build on a beam or shelf, in which situation it would be protected from 

 damp and other casualties to which it would be exposed under ground. 

 Now the wasp is perfectly conscious of this, and selects her materials 



