BACTERIA FIXING ATMOSPHERIC NITROGEN 105 



reported appreciable gains in nitrogen by this organism. 10 The idea 

 then originated to utilize this organism for soil inoculation and a special 

 preparation "alinit," in a powdered form, was placed on the market. 

 This proved to be a failure, but aroused great interest and expectations 

 among the farmers. Actually this organism was found to be unable to 

 fix any nitrogen. 11 - 12 



The important contribution to the subject of non-symbiotic nitrogen- 

 fixing bacteria, next to Winogradsky's work, was the isolation of the 

 aerobic organisms Azotobader chroococcum and Azotobacter agile by 

 Beijerinck. 13 In addition to the Azotobacter group, Beijerinck and 

 Van Delden 14 also found that various forms of the genus Granulobacter 

 (which are actually varieties of Bac. asterosporus (A.M.) Mig.) are 

 capable of fixing nitrogen. A number of other bacteria, commonly 

 found in the soil are also able to fix small amounts of nitrogen on arti- 

 ficial culture media, especially when freshly isolated from the soil. 



Algae, fungi and actinomyces do not fix any atmospheric nitrogen. 

 However, symbiosis between nitrogen fixing bacteria and algae has been 

 established. 15 - 16 Symbiosis is also probable between bacteria and certain 

 non-leguminous plants, like Alnus, Eleagnus, Myrica, Coriaria, Ceano- 

 thus, the bacteria forming nodules on the roots of these plants. Sym- 

 biosis between bacteria and leaves of certain plants was observed in the 

 case of Pavetta, 17 Ardisia, 18 Kraussia. 19 Knots are formed at the place of 



10 See also Beijerinck, M. W. L'influence des microbes sur la fertilite du sol 

 et la croissance des vegetaux superieurs. Arch. Neerl. Sci. Exact. Nat., Ser. II, 

 8: VIII-XXXVI. 1904. 



11 Stutzer, A., and Hartleb, R. Untersuchungen fiber das im Alinit enhaltene 

 Bakterium. Centrbl. Bakt., II, 4: 31-39, 73-77. 1898. 



12 Kriiger, W., and Schneidewind, W. Untersuchungen uber Alinit. Landw. 

 Jahrb. 28: 579-591. 1899. 



13 Beijerinck, 1901 (p. 104). 



14 Beijerinck, M. W., and Van Delden, A. Uber die Assimilation des freien 

 Stickstoffs durch Bakterien. Centrbl. Bakt., II, 9: 3-43. 1902. 



16 Reinke, J. Symbiose von Volvox und Azotobacter. Ber. deut. bot. Ges. 

 21: 482-484. 1903. 



16 Fischer, H. Uber Symbiose von Azotobacter mit Oscillarien. Centrbl. 

 Bakt. II, 12: 267-268. 1904. 



17 Faber, F. C. Das erbliche Zusammenleben von Bakterien und tropischen 

 Pflanzen. Jahrb. wiss. Bot. 51: 285-375. 1912; 54: 243-264. 1914. 



18 Miehe, H. Die sogenannten Eiweissdrusen an den Blattern von Ardisia 

 crispa A. D. C. (V. M.). Ber. deut. bot. Ges., 29: 156-157. 1911; 34: 576-580. 

 1916. Weitere Untersuchungen tiber die Bakteriensymbiose bei Ardisia crispa. 

 II. Die Pflanze ohne Bakterien. Jahrb. wiss. Bot. 58: 29. 1917. 



19 Georgevitch. A new case of symbiosis between a bacillus and a plant. 

 Bull. Bot. Garden Kew, 1916, p. 105. 



