82 DROSERA ROTUNDIFOLIA. [Cdap. IL 



tions of certain salts, and of too great heat, whilst weaker 

 solutions of the same salts and a more gentle heat cause 

 movement. We shall also see in future chapters that various 

 other fluids, some vapours, and oxygen (after the plant has 

 been for some time excluded from its action), all induce in- 

 flection, and this likewise results from an induced galvanic 

 current.* 



* My son Francis, Ruklod by nection with the Becondary coll 



the observations of Dr. Burdon of a I)u Bois Induction apparatus 



Sanderson on Dionsca, flnds that, are inserted, the tentacles curve 



If two needles are Inserted Into Inwards In the course of a few 



the blade of a leaf of Drosera, minutes. My son hones soon to 



the tentacles do not move; but publish an account of his obser- 



that, if similar needles in con- vutlous. 



