The Algae 



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Fig . 27 s- Fresh-water algae. The upright filaments are, from left to right : CEdogonium, 

 producing swimming spores, eggs, and sperms ; Microspora, forming resting spores and 

 swimming spores ; and Ulothrix, forming swimming spores and gametes. The hori- 

 zontal filaments are Spirogyra (left) and Vaucheria (right). Highly magnified. 



