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permanent and visible here as in millet. The series of experiments with infected barley and with 

 wheat substantiated in short the earlier results with millet. In this can be recognized no proof 

 that any assimilation of free nitrogen takes place, caused by parasites in the host plants, and we 

 can say directly that the host plant infected with smut is here exactly as dependent on nitrogen 

 compounds as are other healthy plants. The negative result of these experiments makes the facts 

 ascertained by Hellriegcl, for Leguminoseae, appear so much the more prominently. The subject 

 is finally limited to the fact that according to our present knowledge only the rhizobia possess 

 the capacity of bringing about assimilation of free nitrogen to any great amount when living 

 parasitically on the roots of Leguminoseae. 



