EXPERIMENT STATION BULLETINS. 



431 



Fig. 5. Photomicrograph of longitudinal section through leaf petiole of mosaic bean plant, showing 

 first stage of division of flagellate and proximity to host cell nucleus. X 1500. 



A. Division of flagella preceding longitudinal binary lission into two flagellates. 



B. Biflagellate organism lying in contact with host cell nucleus. 



C. Nuclei with dark-staining nucleoli in center. 



FiQ- 6. Flagellate from bean plant dividing by longitudinal binary fission. 



A. Two daughter flagellates. 



B. Flagellum partially divided. 



X.1800, 



