FIG. 24. A PLANT OF A SINGLE CELL (Sphcerella pluvialis). 



In the upper left-hand corner are seen the plants in t'he motile stage. To the right one more highly magnified 

 and showing the cell-wall (CM>), protoplasm (p), nucleus (n), and flagella (,/), arising from the clear part of the 

 protoplasm and piercing the cell-wall. Below to the left is a plant that has passed into the still condition : and 

 beside it one that has divided into four within the cell-wall. 



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