442 THE ALGAE 



This scheme must be regarded as a great advance on the other 

 classifications, but at the same time it does not seem to take ade- 

 quate account of the effect of environment and, furthermore, it is 

 primarily of use for the marine algae and does not take into con- 

 sideration the numerous fresh- water and terrestrial species. 



Cedergren (1939) pubUshed a Hfe form scheme based primarily 

 upon the nature of the medium and secondarily upon the nature of 

 the substrate. This scheme can be considered as excellent in so far 

 as it classifies the algae in a more general sense. 



Series A. Terrestrial Algae. 



(i) Terricolae (on the earth). (4) (a) Epiphytes. 



(2) (a) Saxicolae (on stone). (b) Endophytes. 



(b) Calcicolae (on chalk). (5) Epizoic forms (on animals). 



(3) Lignicolae (on wood). (6) Succicolae (gelatinous). 



Series B. Soil Algae (in the earth). 



Series C. Water Algae. 



(i) Nereider (river and stream (4) (a) Epizoic forms, 

 algae). (b) Endozoic forms. 



(2) Limnaeider (lake algae). (5) Plankton (small floating algae). 



(3) (a) Epiphytes. (6) Pleuston (large floating algae). 

 (b) Endophytes. (7) Neuston. 



Of all those so far published, however, Feldmann's appears to be 

 the most workable. The real test will come if and when it is em- 

 ployed to give biological spectra, and if the spectra from different 

 localities, e.g. temperate and tropical regions, show a distinct differ- 

 ence then it should prove possible to extend its use as a means of 

 comparing the vegetation from different regions. Such differences 

 may be expected to open up problems, the solutions of which 

 should yield us valuable information concerning the general biology 

 and ecology of the species concerned. 



REFERENCES 



Bennett, T. and Pope, E. C. (i953)- Aust. J. Mar. Fr. Wat. Res., 4 (i)j 105. 

 Borgesen, F. (1934). Det. Kgl. Danske Vidensk. Selsk. Biol. Meddel, 11, 1. 

 Borgesen, F. and Jonsson, H. (1905). Botany of the Faeroes, 3. Copen- 

 hagen. 

 Cedergren, G. R. (1939). Bot. Notiser, 97. 



