56 



THE TISSUES OF PLANTS 



tion of cells already existing, whioh causes growth or the 

 extension of the parts of plants. In this resi^eot precisely, 

 the same laws operate in plants composed of a single row 

 of cells, as when nature works on a more enlarged scale. 

 The most important physiological truths may therefore be 

 learned from vegetation apparently insignificant. " JVaiura 



miranda est 



maxime m iiunimis. 



Fig. 13. 



^tp<g«/ 



Branclimg summit of a fresli water plant, Conferim glamerat'a, magaified, 

 showing at upper a, the partitions forming by the infolding process, and at 

 lower a, the partitions complete. 



* Linnasus. 



