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TRANSFORMATIONS OF INSECTS. 
well known to most of us. It is made up of two very sharp stylets, 
which are mounted upon scales attached to the last segment of 
the abdomen, there being two valve-like sheaths which encase, and 
HEAD OF THE HIVE BEE, MAGNIFIED, WITH THE PIECES OF THE MOUTH 
MUCH SEPARATED FROM EACH OTHER. 
protect them. The poison glands are formed by two twisted 
tubes which lead into a large reservoir, the small opening of which 
is in a tube that emerges between the piercing stylets. When the 
bee is about to sting, it contracts the muscles of its abdomen 
and forces out the stylets, and the pressure exercised in doing 
this gives out a drop of venom, which runs along the perforating 
instruments into the wound inflicted by them. 
When a swarm of bees has taken possession of a cavity — of a 
