ALGOLOGICAL NOTES 



327 



but conspicuous granules, the nature of which has not been deter- 

 mined. No pigment-spot (stigma) is present. 



The movements of this organism deserve special notice. When 

 I received the specimens they were too sluggish to enable me to 

 study their movements properly, but Mr. Scourfield has supplied 

 me with some interesting notes thereon. In normal progression 

 through the water, which is fairly rapid, the body of the cell is 

 imshecl in front by the movements of the cilia ivhich are carried 

 behind. In other words, the organism moves backiuards {vide 



Fig. 3. — Scourfieldia complanata. A-C, three individuals stained with 

 iodine; cli, chloroplast ; n, nucleus; v, vacuoles (2?). A and B, seen from 

 the front; C, side view showing compression of cell. D, side view of individual 

 showing resting position of cilia in living cell. E, diagram to show the direction 

 and the nature of the movements. F, diagram to show cross-section of cell 

 and nature of chloroplast. A-E, x 2000. 



fig. 3, E). This is the reverse of the usual method of propulsion 

 in the Chlamydomonadeae. During progression the body oscillates 

 rapidly from side to side, as indicated in the diagrammatic fig. 3, E. 

 When the organism was at rest the two long cilia were arched 

 backwards, each forming a wide arc. The distal portions of the 

 cilia became anchored to the glass, and the body then swayed 

 about by jerky movements of the cilia. Fig. 3, D, represents this 

 resting position of the organism viewed from the side. It will be 

 noticed that the plane containing the cilia is at right angles to 

 the plane of compression of the cell. 



