58 PLANT GEOGRAPHY 



The character of the vegetation that will occupy such 

 ground depends partly on the chance of the first comer, 

 partly on the various means of dispersal and multiplica- 

 tion possessed by plants, partly on soil-conditions, and 



FIG. 3. Vertical Zonation or Complementary Society of (i) York- 

 shire Fog (Holcus), (2) Bracken, and (3) Bluebells. 



(By Dr. T. W. Woodhead.} 



then ultimately on competition. Obviously, the first 

 comer is likely to be some neighbouring species. 



SUCCESSION. On the occasionally inundated and 

 salt-saturated deposits of the shore, Algae will be followed 

 by such halophytes as Salicornia, Salsola, Crab-weed 

 (Obione portulacoides Moquin), and other Chenopodiacece, 



