i6o THE LORE OF THE HONEY-BEE 



hooks along its top edge, while the lower edge of 

 the upper wing is flanged or folded back. In 

 flight the hooks on one wing engage with the 

 flange on the other, and thus the wings on each 

 side are automatically locked together, forming one 

 continuous air-resisting surface. This combined 

 wing is very flexible throughout, except at its 

 upper edge, where it is stiffened by the main rib. 

 In action, therefore, — the force being applied 

 practically to the edge alone, which resists the air 

 while the rest of the wing bends to it — the result 

 is that the whole wing becomes an oscillating, 

 inclined plane, whose inclination, forward on the 

 down-stroke, is still forward on the up-stroke, 

 because the plane-inclination reverses itself auto- 

 matically. 



From this it will be understood how the flexible 

 wings of the bee are used in straightforward 

 flight ; but, seeing that the wings themselves are 

 incapable of independent or irregular action, it is 

 not yet clear how the bee contrives to steer herself, 

 rising or descending, or turning sideways, just as 

 the mood seizes her. It is here that the reason 

 for the peculiar construction of her body becomes 

 plain. The fine link which unites her abdomen 

 to her thorax is really an universal joint, actuated 

 by a series of powerful cross-muscles, and the bee 

 steers herself through the air by using the weight 

 of the lower half of her body as a counterpoise. 

 By swinging her heavy abdomen forward or back- 



