514 



THE UNIVERSE. 



It was also thought that the direction of the roots was 

 due to their trying to escape the hght, but ];)y means 

 of exjDeriments in which suspended plants were lighted 

 from below, it was ascertained that these organs directed 

 themselves towards the light. Hence this hypothesis really 



11 ^ -^^ 

 -I t H^>w< -''La 



;\ - 





261. Roots Lighted from below and directing tliemselves toii'ard.s the Lislit. 



explains the cause of the direction which plants take no 

 better than the others.' 



In proportion as the embryo is developed, the coty- 

 ledons, as ]Malpighi remarked, become filled with vessels, 

 the office of which is to secrete the first nutritive fluids of 



1 M. Blourleau, in a memoir read before the French Academy, stated that 

 exposure of some seeds to an induced electric ctirrent has the effect of makin" the 

 stem and leaves grow down into the earth, while the roots come up and take their 

 place. — Tr. 



