3i4 SPECIAL INSTINCTS. [Chap. VIH. 



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 inter- 

 sected 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 which 

 thus tend to intersect. Hence, each cell consists of an 

 outer spherical portion, and of two, three, or more flat 

 surfaces, according as the cell adjoins two, three, or 

 more other cells. "When one cell rests on three other 

 cells, which, from the spheres being nearly of the same 

 size, is very frequently and necessarily the case, the three 

 flat surfaces are united into a pyramid ; and this pyramid, 

 as Huber has remarked, is manifestly a gross imitation 

 of the three-sided pyramidal base of the cell of the hive- 

 bee. As in the cells of the hive-bee, so here, the three 

 plane surfaces in any one cell necessarily enter into 

 the construction of three adjoining cells. It is obvious 

 that the Melipona saves wax, and what is more important, 

 labour, by this manner of building ; for the flat walls 

 between the adjoining cells are not double, but are of the 

 same thickness as the outer spherical portions, and yet 

 each flat portion forms a part of two cells. 



Eeflecting on this case, it occurred to me that if the 

 Melipona had made its spheres at some given distance 

 from each other, and had made tbem of equal sizes and 

 had arranged them symmetrically in a double layer, 

 the resulting structure would have been as perfect as 

 the comb of the hive-bee. Accordingly I wrote to Pro- 

 fessor Miller of Cambridge, and this geometer has 

 kindly read over the following statement, drawn up 

 from his information, and tells me that it is strictly 

 correct : — 



