DESCRIPTION OF FIGURES. 



Fig. 



1. — A small "still" cell of Protococcus pluvialis, 

 revived after desiccation. The contents gru- 

 mous, almost filling the cell-membrane. 



2. — A very large cell, in which the red, finely granular 

 contents, fill up the membrane, and have in the 

 centre a clearer space, (cytoblast ?) 



3. — A green cell with chlorophyll-vesicles, containing 

 an excentric, reddish, lighter-coloured vesicle 

 (nucleus ?) surrounded by an opaque red ring. 



4. — A cell which had been dry for six years, under- 

 going segmentation after its revival ; one half is 

 green and granular ; the other red, presenting an 

 oil-like substance. 



5. — A cell which has assumed an elliptical figure pre- 

 paratory to its dividing. 



6. — Division further advanced. 



7. — Completed division. The secondary cells appear 

 to have a cellulose coat, and are surrounded by 

 the mother-cell, which has become gelatinous. 



8. — ^Division into four. 



9. — The same, still surrounded by the parent-cell. 

 10. — Commencement of division; a green, small cell, 

 with a red zone at the border, and red central 

 substance, as well as a lighter coloured nucleus. 

 11. — A "still" cell, containing, within a distant, dense, 

 colourless coat, a coloured globule also surrounded 

 with a membrane. 

 12. — A large naked zoospore, green, with red central 

 substance, and a colourless spot at the anterior 

 end, with two vibratile cilia, originating, either in 

 the division of an encysted zoospore or from a 

 " stiU" cell. 

 13. — An irregular-shaped, quadrangular, flat, Euglena- 

 hke zoospore, with chlorophyll-vesicles, colourless 

 anterior end, and two cilia. 



36 



