474 THE UNIVERSE. 



which we should never think of meeting with in the 

 vegetable kingdom. When Von Martins was traversing 

 the savannahs of tropical America, where it abounds, he 

 observed that the sound of his horse's hoofs at a distance 

 made all the sensitive plants contract as if they had been 

 frightened. A ray of sunlight, or the shadow of a cloud 

 even, is enough to produce a manifest change in the midst 

 of them. 



Such very singular phenomena ought to suffice to make 

 us suppose that the vegetable fibre conceals in its hidden 

 folds some traces of the structure which everywhere pre- 

 sides over animal life. Dutrochet even thought he had 

 found in it the regulator of so many mysterious actions 

 — a nervous system. According to him this structure 

 is represented by the granulations interposed between 

 the cells. But with the most powerful microscope the 

 eye cannot perceive anything that can be identified with 

 the nerves of animals. 



Although the existence of nerves in plants may still 

 be matter of doubt, it is none the less certain that the 

 irritability shown l^y the sensitive plant seems to be abso- 

 lutely under the empire of organs analogous to nerves, 

 as it is influenced by the same agents and in the same 

 manner as animals. Narcotics weaken its sensibility as 

 they weaken ours. If opium be sprinkled upon the plant 

 it ceases to feel irritants, and no longer contracts; it is 

 paralyzed. And, as we have said, an electric shock kills it. 



But a still more extraordinary phenomenon is, that 

 this plant knows, like ourselves, how to accommodate 

 itself to circumstances. Desfontaines, having placed 

 one in his carriage on a journey, saw it contract all its 

 leaves so soon as ever it felt the shaking of the wheels. 

 Then, strange to say, while the journey was still continued. 



