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method by which he obtained Diatomeae in pure culture. For this 

 purpose, silica-gel plates, to which had been added dipotassium 

 phosphate and ammonium chloride, appeared especially useful; the 

 technique of preparation of such plates is very carefully described. 

 These pure cultures were used by Beijerinck to demonstrate the 

 formation of fat as an assimilation product of these algae. 



From the above very condensed survey it will be apparent that in 

 the study of algae also, Beijerinck has done pioneer work. 



