PLATE 12. 



NiTROOEN-FlXING BACTERIA ill sUu IN NODULE ON ROOTLET OF PEA. 



X 400. 





01^* >' 



Nitrogen-Fixing Bacteria in situ in Root-Nodule 

 OF Pea. (Section of Noduk). x 500. 



Nitrogen-Fixing Bacteria in aitu in Root-Nodule 

 OF Pea. (Section of Nodvle). x GOO, 



[To faxe page 134, 



