in] GREEN CELLS OF CONVOLUTA 99 



food from two sources from ingested plants and 

 animals and from its green cells. 



This second phase is succeeded by a third, in 

 which C. roscoffensis, having ceased to ingest solid 

 food, is nourished, in the same manner as the colour- 

 less non-chlorophyllous tissues of a green plant are 

 nourished, by the products of the photosynthetic 

 activity of its green cells. 



Last stage of all which ends this strange eventful 

 history: the animal digests its green cells, and, 

 having done so, dies. 



In the first phase, the mode of nutrition is 

 animal- wise : in the second, part animal-, part plant- 

 wise : in the third, altogether plant- wise or holo- 

 phytic : and in the fourth, autotrophic, that is by 

 living on itself. 



Convoluta paradoxa is like unto C. roscoffensis, 

 except that its experiments in nutrition stop, under 

 normal circumstances, at phase two. Under artificial 

 conditions, however, it behaves like its ally, lives for 

 a while like a plant at the expense of the products 

 of photosynthesis of its yellow-brown cells, and, 

 finally, driven to digest these cells, prolongs its life 

 autotrophically. 



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