BY R. GREIG-SMITH. 



611 



A medium containing saccharose and citrate of potash in place 

 of dextrose and sodium phosphate was used in the following 

 experiment; each 20 c.c. test received 0-1 c.c. of twice normal 

 sodium carbonate (approximately 10%). The slimes were 

 removed as in the previous experiment at the end of the first 

 week and finally on the 37th day.* 





Bhizobium alone. 



Bhizobium and 

 Bac. levaniformans. 



Eace. 



Slime, 

 grms. 



Nitrogen 

 gained, 

 mgrms. 



Slime, 

 grms. 



Nitrogen 

 gained, 

 mgrms. 



Robinia 



S 

 3 



10 



1 



2 

 1 



1 

 



13 



12 

 10 



7 



2 



Lupin "a" 



2 





1 



,, "d" 



2 



It has been already shown that the acidophile race, Lupin "d," 

 forms very little slime from saccharose in alkaline medium, and 

 this experiment, while confirming the earlier result, shows that 

 there is no fixation with nitrogen. But with the co-operation of 

 Bac. levaniformans, which inverts the saccharose, there is a 

 formation of slime and a gain of nitrogen. 





Bhizobium alone. 



Bhizobium and 

 Bac. levaniformans. 



Eace. 



Slime, 



grms. 



Nitrogen 

 gained, 

 mgrms. 



Slime, 



grms. 



Nitrogen 

 gained, 

 mgrms. 



Tare 



5 

 8 

 5 

 6 

 3 

 4 

 12 

 3 



1 

 1 

 2 



3 



2 



1 

 3 



1 



9 

 3 

 2 

 2 



6 

 7 



10 

 13 



2 



Lupin (Kr;il) 



Bean ,, 



2 

 2 



Pea ,, 



3 



Pea (March) 



Lupin "a" 



"c" 



"d" 



3 



2 

 3 

 3 



* With sodium phosphate in the medium, the slimes are generally acid, 

 and with citrate they are usually alkaline. It is necessary to acidify the 

 agar, etc., of the citrate tests, before driving off the water, preliminary to 

 the moist combustion. When this is not done, a volatile nitrogenous sub- 

 stance is driven off. 



