15 



stances without any communication with 

 one another. How admirably suited also 

 are these structures to exigencies unfore- 

 seen by the artificers. Some hornets build 

 the exterior of their nests with aggluti- 

 nated leaves and the Interior cells with the 

 same materials, reduced to the state of paste 

 or mortar, whilst the bees which build In 

 hollow trees, requiring no protecting walls, 

 merely build a comb with plates of wax 

 resembling tiles, which are prepared and 

 formed between layers constructed for this 

 purpose on the surface of their bodies. 

 This apparatus and its products have been 

 exhibited by Mr. Hunter In his museum, 

 and you know his very interesting paper on 

 this subject which is published in the phi- 

 losophical transactions. The greater num- 

 ber of animals, however, have no necessity 

 nor propensity to build j so that this very 

 curious instinct Is also a very partial 

 one. 



