GENERAL RELATION OF THE PHVLOGENETIC LINES. 37 



labor. Since there are also numerous different 

 kinds of adaptation, a phyletic line may divide at 

 each point into several adaptive forms, which appear 

 in the taxonomic system as species, genera, often 

 even as whole families, while in other cases various 

 degrees of organization have appeared in one family. 



20. LAWS OF EVOLUTION OF THE PLANT KINGDOM. 



In the sub-organic kingdom, which precedes the 

 plant and animal kingdoms, (see page 5), there are 

 gradually formed from the spontaneously generated 

 plasma independent cells with their characteristic 

 properties, i.e. , growth by intussusception of micellae, 

 formation of a plasmic cuticle, and a non-plasmic 

 membrane about the same, division of the cells, 

 separation of the cells thus formed, and free cell 

 formation within the cell contents. These proper- 

 ties are inherited from the sub-organic kingdom by 

 the plants and animals which follow in the next 

 stage of phylogeny. The evolution of the plant 

 kingdom proceeds through the following regular 

 processes, which continue to operate through the 

 entire phylogenetic series. 



Law of Phylogenetic Combination. The simplest 

 of all plants are cells of round form, which grow 

 and reproduce themselves by division, budding or 

 free cell formation. From the fact that the younger 

 generation of cells, instead of separating from each 

 other and growing to independent plant individuals, 



