The Vegetation of Lakes and Swamps 

 in Japan. 



by 



H. Nakaiio. 



I. Teganuma (Tega-Swamp). 



I. Introduction. 



Many investigations in the plant distribution of lakes and 

 swamps in Europe and North America reveal us that there 

 always occur plant associations arranged in zones. We owe 

 the researches upon these zones in Europe to Magnin/^ Schro- 

 TER,^^ Brand/"^^ Yapp^) &c, and those in the United States of 

 America to Coules,'^ Reed,^^ Transeau^^ and others. 



In Japan, such an exploring has never been undertaken till 

 present. So I made an attempt to find out what a zonal arrange- 

 ment exists in Japanese lakes and swamps, and to investigate 

 what ecological factors have influenced the arrangement. 



We have many large reed-swamps (after Warming's classi- 

 fication of swamps'^^) in Japan, as Kasumigaura, Kitaura, 

 Inbanuma, Ushikunuma, Teganuma and others. For several 

 years I have been studying especially the plant formation of 

 Teganuma, and have distinguished five zones in it. The origin 

 and explanation of this plant formation are the chief object of 

 the present report. 



1) and 2) cited from Warming's Oecology of plants, 1909, p. 188. 



As to the zonal arrangement of plant associations of lakes, we may refer also 

 Schimper's Pflanzen- Geographic, 1908, p. 850. 



3) Bot. Centra]b. Bd. 65, 1896. p. 1-13. 



4) New phytologist, 1908, p. 69. 



5) B)t. Gaz. Vol. 31, 1901. p. 145. 



6) Ditto, Vol. 34. 1902. p. 129. 



7) Ditto, Vol. 36. 1904 p. 403. 



8) Warming's "Keed Swamps" may contain lakes and swamps in a limnolugical 

 sense. 



