THE BEE. 



described, and avail themselves of the ready-made cavities of trees, 

 or any other object which answers their purpose. Kirby mentions 

 the example of nests of this kind found by himself and others, 

 constructed in the inside of the lock of a garden-gate. 



44. A proceeding has been ascertained on the part of these 

 insects in such cases, which it is extremely difficult to ascribe to 

 mere instinct, independent of some intelligence. Wherever the 

 nest may be constructed, the due preservation of the young requires 

 that until they attain the perfect state, their temperature should 

 be maintained at a certain point. So long as the material sur- 

 rounding their nest is a very imperfect conductor of heat, as 

 earth or the pith of wood is, the heat developed by the insect, 

 being confined, is sufficient to maintain its temperature at the 

 requisite point. But if, perchance, the mother-bee select for her 

 nest any such locality as that of the lock of a gate, the metal, 

 being a good conductor of heat, would speedily dissipate the animal 

 heat developed by the insect, and thus reduce its temperature to 

 a point incompatible with the continuance of its existence. How 

 then does the tender mother, foreseeing this, and consequently 

 informed by some power of the physical quality peculiar to the 

 metal surrounding the nest, provide against it ? How, we may 

 ask, would a scientific human architect prevent such an even- 

 tuality ? He would seek for a suitable material which is a non- 

 conductor of heat and would surround the nest with it. In fact 

 the very thing has occurred in a like case in relation to steam- 

 engine boilers. The economy of fuel there rendered it quite as 

 necessary to confine the heat developed in the furnace, as it is to 

 confine that which is developed in the natural economy of the 

 pupa of the bee. The expedient therefore resorted to is to invest 

 the boiler in a thick coating of a sort of felt, made for the pur- 

 pose, which is almost a non-conductor of heat. A casing of 

 sawdust is also used in Cornwall for a like purpose. By these 

 expedients the escape of heat from the external surface of the 

 boiler is prevented. 



45. The bee keeps its pupa warm by an expedient so exactly 

 similar, that we must suppose that she has been guided either by 

 her own knowledge, or by a power that commands all knowledge, in 

 her operations. She seeks certain woolly leaved plants, such as the 

 stachys lanata or the agrostemma coronaria, and with her 

 mandibles scrapes off the wool. She rolls this into little balls, 

 and carrying it to the nest, sticks it on the external surface by 

 means of a plaster, composed of honey and pollen, with which 

 she previously coats it. Thus invested, the cells become impervious 

 to heat, and consequently all the heat developed by the little 

 animal is confined within them. 

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