Chap. VII. CELLS OF THE HIVE-BEE. 225 



I was led to investigate this subject by Mr. Water- 

 house, who has shown that the form of the cell stands 

 in close relation to the presence of adjoining cells ; and 

 the following view may, perhaps, be considered only as 

 a modification of his theory. Let us look to the great 

 principle of gradation, and see whether Nature does not 

 reveal to us her method of work. At one end of a short 

 series we have humble-bees, which use their old cocoons 

 to hold honey, sometimes adding to them short tubes of 

 wax, and likewise making separate and very irregular 

 roimded cells of wax. At the other end of the series we 

 have the cells of the hive-bee, placed in a double layer : 

 each cell, as is well known, is an hexagonal prism, with 

 the basal edges of its six sides bevelled so as to join on 

 to a pyramid, formed of three rhombs. These rhombs 

 have certain angles, and the three which form the pyra- 

 midal base of a single cell on one side of the comb, enter 

 into the composition of the bases of three adjoining cells 

 on the opposite side. In the series between the extreme 

 perfection of the cells of the hive-bee and the simplicity 

 of those of the humble-bee, we have the cells of the 

 Mexican Melipona domestica, carefully described and 

 figured by Pierre Huber. The Melipona itself is inter- 

 mediate in structure between the hive and humble bee, 

 but more nearly related to the latter : it forms a nearly 

 regular waxen comb of cylindrical cells, in which the 

 young are hatched, and, in addition, some large cells of 

 wax for holding honey. These latter cells are nearly 

 spherical and of nearly equal sizes, and are aggregated 

 into an irregular mass. But the important point to 

 notice, is that these cells are always made at that 

 degree of nearness to each other, that they would have 

 intersected or broken into each other, if the spheres had 

 been completed ; but this is never permitted, the bees 

 building perfectly flat walls of wax between the spheres 



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