CHAPTER IV 

 THE ORIGIN OF LAND PLANTS 



THE algae seem to have reached their culmina- 

 tion in such great marine forms as the 

 giant kelps of the Pacific. These highly special- 

 ized brown seaweeds and the very peculiar red 

 algae are the dominant plants of the ocean at the 

 present time, and have evidently best solved the 

 problem of life in salt water; to their peculiar 

 environment are no doubt due their most marked 

 characteristics. There is little reason to suppose that 

 any higher plant types have arisen from either the 

 brown or the red algae, although it has been sur- 

 mised that there may be a possible connection be- 

 tween the latter and certain fungi. 



Green Algae the Ancestors of the Land Plants. 

 The green algae, on the other hand, probably repre- 

 sent the remnants of the primordial vegetation 

 which have persisted in fresh water without any 

 very great alteration down to the present time. It 

 is from forms allied to these primitive green algae 

 that there is good reason to suppose the first land 

 plants arose. 



Except for differences in temperature, conditions 

 so 



