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Elementary Biology, 



to catch and kill by means of remarkable modification of 

 their leaves. The number of species which possess this 

 power is not great. They belong to widely separated 

 families, and are found scattered all over the globe. They 

 comprise some well-known forms, such as the famous 

 pitcher-plant, Nepenthes, the familiar Drosera or sundew, and 

 Dionaa, Venus's fly-trap. On examination we find that itis 



FIG. 109. LEAF OF Drosera. (Darwin.) 



FIG. 108. Drosera rotundi- 

 folia. (Bentham.) 



possible to make a physiological classification of carnivorous 

 plants according to the way in which they treat the animals 

 they catch. One group is represented by the sundew, which 

 is able, not only to kill, but to digest the insects which it 

 catches ; the other, represented by Sarracenia, is unable to 

 do more than absorb the gases which arise by decomposition 

 of the dead bodies of the insects caught by the leaf. A, 



