BY R. GREIG-SMITH. 



613 



tions in the moisture^content of the slimes; and (3) the auto- 

 digestion of the slimes. Autodigestion was very marked with 

 some races, e.g., Pea, Bean, Tare and Lupin(Kral), when the 

 experiment occupied more than a week. 



Average Gain op Nitrogen per Gram of Slime. 



Slime, grms. 



None 



1 



2 



3 



4 



5 



6 



7 



S 



9 



10 



11 



12 



13 



14 



15 



22 



Nitrogen gain- 





































ed, mgrams. 







0-2 



1-2 



1-3 



0-7 



1 



1-5 



1-5 



1-7 



2 



1-5 



2 



2 "5 



2-5 



3 



4 



4 



No. of Tests 







in average ... 



3 



5 



5 



9 



3 



6 



2 



4 



3 



1 



4 



2 



4 



2 



1 



1 



1 



Average Weight of Slime per Milligram or Nitrogen Gained. 



Nitrogen gained, mgrms 

 Slime formed, grms 



None 

 2-6 



1 



5-7 



2 



7-1 



3 



8-6 



4 

 16-3 



No. of tests in average 



16 



14 



16 



7 



3 



Taken as a whole, the research shows that 



(1) Races of Rhizobium leguminosarum can fix atmospheric 



nitrogen in artificial culture; 

 (•J) The fixation is coincident with and proportional to the 



formation of slime; 

 (3) Under conditions that preclude the formation of slime, 



there is no fixation; 

 (i> Conditions, such as the presence of another bacterium, 



which assist the formation of slime, also assist fixation; 

 (5) It is a matter of indifference whether the medium is acid 



or alkaline. 



The simultaneous production of slime and fixation of nitrogen 

 have not been noted by Moore or by Lohnis, but Maze clearly 

 points out the relation. Translating from a part of his conclu- 

 sions (p. 24) we read — " From the beginning of our experiments, 

 our attention has been strongly drawn to the abundance of slime 



