VENUS' FLY-TRAP 



danger. They are almost certain to die of overfeeding or 

 indigestion. It is impossible to keep people from giving 

 them too much to eat. 



This wonderful little plant shows quite distinctly that 

 there must be some way of sending messages in its leaves. 

 Somehow the message travels from the tentacle which the fly 

 has touched, down the stalk into the leaf, and up into the 

 other tentacles, and tells them that there is something worth 

 stooping for. 



No one has explained this, and probably no one will ever 

 do so. 



The last, and in some ways the most interesting, of all 

 these carnivorous plants is Venus' Fly-trap {Dioncea rmcsci- 

 pula\ which grows in North America from Rhode Island 

 to Florida. 



It is a quite small herb with a small circle of leaves which 

 lie flat on the ground. Each leaf ends in a nearly circular 

 piece which is divided by a very marked midrib. The two 

 semicircular halves have a series of teeth along their edges ; 

 these margin teeth are stiff* and a little bent upwards. In 

 the centre of each half there are three small hairs. On look- 

 ing closely at these hairs one finds that each has a joint near 

 the base ; all over the centre of these leaf halves there are 

 scattered glands which secrete ferments intended to digest 

 any animal matter. 



The really interesting point is connected with these central 

 jointed or trigger hairs ; they are extremely sensitive. But 

 when they are touched it is not they themselves that are 

 aff*ected, but the entire circular end of the leaf ! 



Suppose an insect wanders on to the leaf and reaches one 

 of these semicircular halves, nothing happens until it touches 

 one of these hairs, but then both halves suddenly close 



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