BEES AND BEE-KEEPING. 



a wound whose maximum depth is T V n -> and whose 

 diameter is -^-Qin., or less than ¥ ^-g- of the area of 

 that inflicted by a common pin. The sting derives its 

 value, as an instrument of attack and defence, from 

 the poison with which it is associated, and which is 

 derived from a gland (pg, A, Plate VI.) having often the 

 astonishing length of i^in. in the worker and i|in. 

 in the queen. In the former, dissection reveals it tra- 

 velling, like two attenuated, nearly transparent threads, 

 over the outside of the chyle stomach, while its ends 

 are swollen into forms resembling the plumber's iron. 

 These are full of curious dotted cells, containing 

 granular matter, and are abundantly supplied with 

 tracheae. The bifid gland unites at some distance 

 from the poison sac {ps). Its structure (H, Plate VII.) 

 is in the divided portion intracellular, and the duct- 

 lets of the cells (I) may be brought into view by treat- 

 ment with liquor potassa. 



The poison it secretes is formed from the blood by 

 cell-elaboration and transformation, and its active 

 principle seems to be formic acid, probably associated 

 with some other toxic agent. If a bee be made to 

 sting a piece of paper stained with litmus, which 

 is a common test for acids, the dye is immediately 

 reddened. On this account, ammonia is often recom- 

 mended to allay the irritation a sting causes, as it 

 is argued that the alkali must act as a neutraliser. 

 Formic acid is poison to the blood of the bee, which 

 dies by a sting from its relative, although it is not in- 

 jurious if taken, in reasonable doses, into the creature's 

 stomach, as food mixed with it is accepted readily, while 

 no untoward consequences are observed {see Diseases). 



