GENERAL CHARACTERISTICS. 



25 



dows by the same process. It was fonnerly asserted that 

 insects cling to the smooth surfaces by air suction, but the 

 above explanation is correct, and you can actually see "the 

 footprints of a fly" on a pane of glass, with the help of a 

 microscope, remnants of the "clammy" substance being quite 

 discernible. By this ingenious arrangement, bees can walk 

 indifferently upon almost anything, since wherever the claws 

 fail, the pulvilli take their place. 



53. "But another contrivance, equally beautiful, remains 

 to be noticed. The pul villus is carried folded in the middle (as 

 at C, fig. 13), but opens out when applied to a surface, for it 

 has at its upper part an elastic and curved rod (cr) which 

 straightens as the pulvillus is pressed down, C and D, fig. 13, 

 making this clear. The flattened-out pulvillus thus holds 

 strongly while pulled, by the weight of the bee, along the sur- 

 face, to which it adheres, but comes up at once if lifted and 

 rolled off from its opposite sides, just as we should peel a wet 

 postage stamp from its envelope. The bee, then, is held se- 

 curely till it attempts to lift the leg, when it is freed at once; 

 and, by this exquisite yet simple plan, it can fix and release 

 each foot at least twenty times per second." — (Cheshire.) 



Fig. 13. 



bee's foot in climbing, showing action of PtXVILLUS. 



(Magnified 30 times. From Cheshire.) 



A, position of the foot in climbing slippery surface or glass ; pv, pul- 

 villus ; fh, feeling hairs ; ati, anguiculus, or claw ; t, tarsal joint. 



B, position of the foot in climbing rough surface. 



C, section of pulvillus just touching flat surface ; cr, curved rod. 



D, pulvillus applied to surface. 



54. The legs of bees, like all other parts of their body, 

 are covered with hairs of varied shapes and sizes, the descrip- 

 tion of which is beyond the limits of this work. We will con- 



