AMERICAN NATURALIST 



THE PROBABLE INFLUENCE OF DISTURBED NUTRI- 

 TION ON THE EVOLUTION OF THE VEGETA- 

 TIVE PHASE OF THE SPOROPHYTE. 



By Geo. F. Atkinson. 1 



In this paper the discussion of the influence of nutrition, 

 applies chiefly to that source of nutrition in plant organs pro- 

 vided with chlorophyll, and presupposes, in general, that the 

 ordinary physiological processes, other than the one which is 

 termed carbon assimilation, are normal. In all such plants 

 some development of this vegetative part of the plant must take 

 place before spore production, or fruiting, of a kind which re- 

 presents a real increase at the time, can be accomplished. 

 Some apparent, but not real, exceptions to this might be noted. 

 In germination of the spores of Oedogonium, frequently spore 

 production takes place without the development of any such 

 vegetative part of the plant, but there is no real increase of the 

 plant substance. This kind of spore production is only a 

 means, perhaps, to tide over some condition unfavorable for 

 the elaboration of the vegetative phase of the plant, which is 

 present at the time and place. In Coleochsete, germination of 

 the oospore results in the formation of a cellular mass, which 



1 Cornell University. 

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