PERFECT SOCIETIES OF INSECTS. 199 



great energy. But if by any means a shadow is cast over 

 any portion of the group, the ventilation ceases there, 

 while it continues in the part which feels the heat of 

 the sun. The same cause produces a similar effect upon 

 humble-bees, wasps, and hornets. 



Amongst the bees, however, it is remarkable that 

 ventilation goes on even in the depth of winter, when 

 it cannot be occasioned by excess of heat. — This there- 

 fore can only be regarded as a secondary cause of the 

 phenomenon. From other experiments, Avhich, having 

 already detained you too long, I shall not here detail, 

 it appears that penetrating and disagreeable odours 

 produce the same efl^ecf^. Perhaps, though Huber 

 does not say tliis, the odour produced by the congre- 

 gated myriads of the hive may be amongst the princi- 

 pal motives that impel its inhabitants to this necessary 

 action. 



Whatever be the proximate cause, it is I trust now 

 evident to you, that the Author of nature, having as- 

 signed to these insects a habitation into which the air 

 cannot easily penetrate, has gifted them with the means 

 of preventing the fatal effects which would result from 

 corrupted air. An indirect effect of ventilation is the 

 elevated temperature which these animals maintain, 

 w ithout any effort, in their hive : — but upon this I shall 

 enlarge hereafter.^ 



Bees are extremely neat in their persons and habi- 

 tations, and I'emove ail nuisances with great assfduity, 

 at least as far as their powers enable them. Some- 

 times slugs or snails will creep into a hive, which with 

 all their address they cannot readily expel or carry out. 



* Ilubcr, ii. 359 — 



