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MANUAL OF POISONOUS PLANTS 



Fig. 19. Algae found in water supplies., a. Protococcus. b, c. Cosmarium, one of the 

 desmids. d. Pediastrum. e. Oscillatoria. f. Nostoc paludosum. g. Closterium, chr — 

 chromatophore. h. Pandorina; 1, gelatinous envelope; 2, cilia, i, ;. {Anabaena flos-aquae)* 

 k* Botrydium granulatum; 2, rhisoids. I and m. Diatoms, n. Zygnema; 1, chromatophore; 

 2, zygospores, o. Spirogyra; 1, 2, 3, 4, different stages in the formation of the zygospores. 

 p., Draparnaldia; 2, thallus. q. Stoneworts (Chara) ; 1, antheridium; 3, archegonium; 5, 

 nodal cells, r. Portion of antheridium with sperm cells. 



