Autotrophic Nitrification in the Ocean 



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Fig. 2a. Nitro.somonas curopaea. 



Fig. 2b. Nitrobacter agills. 



Fig. 2c. Marine nitrifying bacteria. 



Fig. 2d. Protozoan-like cell just after division. 



Fig. 2e. Protozoan-like cell just prior to division. 



Fig. 2f. Hypertrophied protozoan-like cell from senile culture. 



