68 INSECT MISCELLANIES. 



Rove beetle (Cherius olens) on the wing. 



immersed a number of bees in water, slightly heated 

 to prevent any effect from torpidity in consequence of 

 cold. 



' When only the head of a bee,' he says, ' was 

 plunged in mercury or water, it did not seem to suf- 

 fer ; but if the head alone remained out of the fluid, 

 the insect stretched out its sucker and gradually 

 swooned away ; if the head and thorax were im- 

 mersed, leaving the abdomen free, it struggled a few 

 minutes and quickly died. The mouths of the spi- 

 racles appearing from this to be in the chest, that was 

 left free, while the head and the abdomen were im- 

 mersed. A bee supported this experiment very pa- 

 tiently, and took flight when released. The action of 

 the spiracles can be best observed by the suffocation 

 of bees in water. Four air-bubbles then become 

 conspicuous, — two between the origin of the neck 

 and the root of the wings, a third on the neck at the 

 origin of the tongue, and a fourth on the opposite 

 extremity of the chest close to its junction with the 

 abdomen. The bee seems to have some power in the 

 retention of air, as the bubbles do not rise to the 

 surface till they acquire sufficient size to overcome 

 the resistance of inspiration or adherence to the sides 

 of the -cavities. By the third and fourth bubbles, the 



