FRESH WATER ALG/€. 



PLATE VII 



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AFTER NATURE 8V DR. M. C. WOOD 



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T. StNCLAtR It SON, PHILAOCLPHIK. 



Fig. T. SCYTONEMA CATARACTOIVI . 

 - S, SCYTONEMA IMMERSUM 



Fig 3. RHAPHIDIUM POLYMORPHUM. 

 •■ 4. PROTOCOCCUS. 



