LIVING PLANTS 



Botany," "from our own vital motions we 

 argue to those of the higher animals, which 

 we comprehend immediately and instinctively 

 from their conduct ; by aid of these the mo- 

 tions of the lower animals also become intel- 

 ligible to us, and further conclusions from 

 analogy lead us finally to plants, whose vi- 

 tality is only in this way made known to us." 

 An illustration of such reasoning is admira- 

 bly set forth by G. H. Lewes, the eminent 

 English psychologist, in his volume on the 

 object, scope and method in the study of psy- 

 chology. He says : "Touch the eye of a frog, 

 and there is at once the response of a reflex 

 closure of the eyelid. Touch the hairs of a 

 venus fly-trap {Dionoeamuscwula), and there 

 is at once the response of a reflex closure of 

 the leaf. Confine the frog and the dionoea 

 under a glass shade, and place there a sponge, 

 over which ether has been sprinkled. Both 

 plant and animal breathe this air in which 

 there is vapor of ether, and as this vapor pen- 

 etrates to their tissues we observe a gradual 

 cessation of all sensibility ; first the reflex 

 actions cease, then the irritability of the par- 

 ticular tissues ceases. Stupor has supervened 

 for both. Now^ remove the glass shade; the 

 vapor dissipates, the fresh air penetrates to 

 the tissues in exchange for the vitiated air, 

 and both frog and dioncea slowly recover 



