PAPER^MAKERS 163 



horizontally with the cells opening downwards. 

 Like the bee, they begin their building at the top 

 of their nest and work downward, but there is 

 this difference, that the bee-comb is attached by 

 its double thickness and each one has its own 

 support ; the single flimsy combs of the wasp are 

 suspended by paper pillars, the first layer to a 

 branch or underground root, and each succeeding 

 comb to the one previously constructed ; so that 

 the entire series of combs has to depend upon 

 the original pillar. 



In a previous chapter we have referred to the 

 idea, still entertained by a few, that the hexagonal 

 form of the bee cells is due to mutual pressure. 

 In the analogous case of the wasp, where the same 

 shape is adopted, observation of the building-up 

 of the comb convinced us many years ago that the 

 hexagon is built as such, and not produced by pres- 

 sure. There is this difference, however, between 

 the cell of bee and wasp — the latter has a base 

 slightly convex on the exterior, and the interior 

 forming a broad inverted cone. This is due to 

 the fact that there is no economy possible in adopt- 

 ing the three rhombs of the bee cell. The upper 

 side of the comb is flat as a whole, but the slight 

 convexity of each cell is patent to the eye, and it 

 is equally evident that the hexagonal form is adopted 

 from the beginning. 



Whence comes the material of the comb ? The 

 wasp cannot produce paper pulp from the plates 

 of her abdomen as the bee produces wax. It is 



