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very delicate poison- glands, which resemble threads, not nearly 

 so thick as a human hair, and white in colour. These glands 

 unite together at their bases and form a short common tube, 

 which opens into the poison sac, in which the venom is retained 

 until it is wanted. The base of the sting is connected with 

 the poison sac, and as soon as the weapon is used, the poison 

 flows down the sting and is injected into the wound. 



