346 SPECIAL INSTINCTS. [Chap. YHI. 



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 de- 

 scribes her spheres so as to intersect to a certain extent ; 

 and then she unites the points of intersection by per- 

 fectly flat surfaces. By such modifications of instincts 

 which in themselves are not very wonderful,— hardly 

 more wonderful than those which guide a bird to make 

 its nest, — I believe that the hive-bee has acquired, 

 through natural selection, her inimitable architectural 

 powers. 



But this theory can be tested by experiment. Follow- 

 ing the example of Mr. Tegetmeier, I separated two combs, 

 and put between them a long, thick, rectangular strip of 

 wax: the bees instantly began to excavate minute 

 circular pits in it; and as they deepened these little 

 pits, they made them wider and wider until they were 

 converted into shallow basins, appearing to the eye per- 

 fectly true or parts of a sphere, and of about the diameter 

 of a cell. It was most interesting to observe that, wherever 

 several bees had begun to excavate these basins near 

 together, they had begun their work at such a distance 

 from each other, that by the time the basins had acquired 

 the above-stated width (i.e. about the width of an 

 ordinary cell), and were in depth about one sixth of the 

 diameter of the sphere of which they formed a part, the 

 rims of the basins intersected or broke into each other. 

 As soon as this occurred, the bees ceased to excavate, 

 and began to build up flat walls of wax on the lines of 

 intersection between the basins, so that each hexagonal 

 prism was built upon the scalloped edge of a smooth 

 basin, instead of on the straight edges of a three-sided 

 pyramid as in the case of ordinary cells. 



