358 TFfE BOTANICAL MAO AZINE. [V.a. xxx. No. ssn. 



peculiar phenomenon, that is the migration of an immense 

 number of svvarmspores groujiing in vertical columns from the 

 surface of the medium to the bottom of the flask. This pheno- 

 menon was explained as a manifestation of negative rheotaxis. 

 The significance of this phenomenon in hydrobiology in nature 

 was suggested. 



5. The positive chemotactic activity of the organism was 

 demonstrated b}' experimentation with the acidic chemicals. 

 It was suggested that it maj' have some biological importance 

 to the nutrition of this organism in nature. 



(). The morphological accounts of the present organism 

 were given and the pectin nature of the cell-membrane was 

 pointed out. 



In conclusion, I have the pleasant duty of thanking Prof. 

 K. Fujii for suggestions and criticisms throughout the work. 

 My thanks are also due to Prof. K. Okamur.\ of the Fishery 

 Institute of the Department of Agriculture and Commerce for the 

 facilities given for the investigation. 



Explanation of Plate. 



Fig. 1. Pliotosrapli showing a collection of tlie swarmspores responded to lie;l>t. 

 The upper dark l)and in the photograpli is tlie image of the gronp of organi.snis at 

 the bottom reflected on tlie surface of warter. 



Fig. 2, Side-view of green columns of organisms moving down from the surface 

 of water towards the bottom of the liask. xl. 



Fig. 3. Pliotograph showing the same. 



Fig. 4. Pliotograph showing both surface- and sidi-view of green columns 

 arranged towards the direction of ray o( light. Source of light being in the direc- 

 tion of tlie top of the page. 



Fig. 5. Swarmsporcs. x27o0. 



Fig. C. The same. X 2750. 



Fig. 7. The same showing "starch"' grains only. X 2750. 



Fig. 8. Resting form. x2750. 



