1909] LIPMAN—EFFECTS OF SALTS ON BACILLUS 115 
In the curve plotted from table VI (fig. 3), we note again a strong 
antagonism between the two salts tested, though it is not as marked 
as in the last series. ‘The curve proves to be more regular than the 
last, probably owing to.the fact that there was practically no variation 
in the temperature throughout the period of incubation. As Lrp- 
“kg 
4mg 
NAEP Eo Sse: Mol), 
Ee Le 7 DO CBA 9% 
Fic. 3.—Antagonism curve, NaCl vs. MgCl. The ordinate at K repre : od = 
ammonia nitrogen in milligrams formed in a pure NaCl solution. The ordinate at 
A represents th "Ses ae formed in a pure MgCl, solution, and the 
ondhontes at the intermediate points represent the amounts formed in various com- 
binations of the two salts as indicated by the corresponding letters in table VI. 
MAN (4) has demonstrated, a constant temperature and equal 
periods of incubation are essential factors in quantitative work in 
ammonification, if results are to be considered comparable. — 
