REV'IEWS. 579 



The Runners of Nephrolepis. 



[Erganziingen z\ir Morphologie vind Anatomie der Auslaufer 

 von. N. Sperlich in Flora, 96, 451, 1906.] 



A paper largely of anatomical contents. 



J. C. W. 



Plankton in Colombo Lake. 



[Apstein C. Das Plankton im Colombo-See auf Ceylon. 

 Sammelausbeute von A. Borgert, 1904-.5. Zool. .Tahrb. ,25, 1907. 

 p. 201.] 



Herr Apstein received collections made by Borgert and by 

 Dr. Willey. They show that there is a marked periodicity of the 

 plankton, which is attributed to changes of monsoon, with the 

 consequent changes of level and of amount of food in the water. 



J. C. W. 



Algse in Ceylon. 



[The subaerial and freshwater Algal flora of the Tropics. 

 Fritsch. Ann. of Bot., 21, AprU, 1907. p. 235.] 



A general consideration of the subaerial and freshwater Algal 

 flora of Ceylon, Part I., Fritsch, Proc. Roy. Soc.,79, 1907, p. 197. 



[Uber einen Fall von Symbiose zwischen zoochlorellen und einer 

 marinen Hydroide. Svedelius. Svensk Bot. Tidsk I. , 1907, p. 32.] 



A series of papers by former visitors. The first two are of 

 special interest to the student of the general distribution of algae. 



J. C. W. 



The Alga Martensia. 



[Ueber den Bau und die Entwicklung der Florideen-gattung 

 Martensia. By N. Svedelius. Kgl. Sv. Vetenskapsakad. Handl, 

 43.] 



Dr. Svedelius collected this alga at Galle, and gives here a 

 detailed account of its structure and development. 



J. C. W. 



