Chap. VII. CELLS OF THE HIVE-BEE. 227 



both layers be formed, there will result a double layer of 

 hexagonal prisms united together by pyramidal bases 

 formed of three rhombs ; and the rhombs and the sides 

 of the hexagonal prisms will have every angle identi- 

 cally the same with the best measurements which have 

 been made of the cells of the hive-bee. 



Hence we may safely conclude that if we could 

 slightly modify the instincts already possessed by the 

 Melipona, and in themselves not very wonderful, this 

 bee would make a structure as wonderfully perfect as 

 that of the hive-bee. We must suppose the Melipona 

 to make her cells truly spherical, and of equal sizes ; 

 and this would not be very surprising, seeing that she 

 already does so to a certain extent, and seeing what 

 perfectly cylindrical burrows in wood many insects can 

 make, apparently by turning round on a fixed point. 

 We must suppose the Melipona to arrange her cells in 

 level layers, as she already does her cylindrical cells ; 

 and we must further suppose, and this is the greatest 

 difficulty, that she can somehow judge accurately at 

 what distance to stand from her fellow-labourers when 

 several are making their spheres ; but she is already 

 so far enabled to judge of distance, that she always 

 describes her spheres so as to intersect largely; and 

 then she unites the points of intersection by perfectly 

 flat surfaces. We have further to suppose, but this is 

 no difficulty, that after hexagonal prisms have been 

 formed by the intersection of adjoining spheres in the 

 same layer, she can prolong the hexagon to any length 

 requisite to hold the stock of honey ; in the same 

 way as the rude humble-bee adds cylinders of wax 

 to the circular mouths of her old cocoons. By such 

 modifications of instincts in themselves not very won- 

 derful, — hardly more wonderful than those winch guide 

 a bird to make its nest, — I believe that the hive-bee 



