THE MOST PRIMITIVE LIVING REPRESENTATIVE OF 

 THE ANCESTORS OF THE PLANT KINGDOM. 



By GEORGE T. MOORE, Ph.D. 

 (Read April 25, igo8.) 



There is but little doubt among botanists that the land flora as 

 it now exists has originated from aquatic ancestors. Both from the 

 morphologic and palseontologic standpoints the evidence corroborates 

 this view. Indeed, the dependence of land plants upon an adequate 

 water supply, together with the fact that in such groups as the 

 Mosses and Ferns, fertilization itself can only be accomplished in 

 the presence of water supplied from some external source, gave rise 

 to the conclusion that the origin of the vegetable kingdom was from 

 primitive plants living in the water, long before there was the more 

 conclusive evidence now existing. 



It would be interesting to inquire into the life histories of certain 

 transitional groups with a view to tracing this migration from water 

 to land. For modern morphological and physiological investigations 

 has enabled us to do this with a considerable degree of certainty. 

 Not only would we be able to show that the establishment of the 

 higher representatives of our land flora had been brought about by 

 certain methods of specialization in lower aquatic or semi-aquatic 

 forms, but it would be possible to indicate to a certain extent at 

 least how this process had been carried on. However such an 

 inquiry would lead us entirely too far afield at this time and it will 

 be necessary to grant without further discussion that the facts are 

 sufficient to sustain the aquatic origin of the higher plants. 



Naturally, in seeking for the primitive ancestors of the vegetable 

 kingdom, attention is at once directed to the algae, the group of 

 plants which to a very considerable extent is more dependant 

 upon the presence of external water for the carrying on of its vital 

 processes than any other. Furthermore, in the present state of our 

 knowledge, such an investigation would not be devoted to the more 



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