: 
B 
; 
F 
T909] LIPMAN—EFFECTS OF SALTS ON BACILLUS III 
example, by the work of OstwaLp (21) in which KCI showed the 
most extreme toxicity of all the salts tested. 
It is also worthy of mention here, as shown above, that the KCl 
curve declines more gradually than the sodium curve beyond the 
concentrations of o.1 m. 
SERIES IV. MAGNESIUM CHLORID 
In the curve drawn on the basis of table IV (fig. I) we notice a 
parallel to the toxicity curve for CaCl,, except that MgCl, is not 
nearly as toxic for B. subtilis as the former. 
While a 0.3 m solution of CaCl, totally: ins: jee 
hibits the ammonifying activity of B. subtilis, Numbers repre- Milligrams of N 
- : * sent tenths m cH; 
the latter will make a fair growth in a solu- MgCl, solution| formed as N 
TABLE IV 
tion of MgCl, of like concentration and form ° 5.60 
an appreciable amount of ammonia. Here ; nares 
again, we find agreement between the be- 3 ao 
havior of B. subtilis and Fundulus in solu- 5 a pi 
tions of MgCl,, as Lors (7, p. 411) found 
that in an m/2 solution of MeCl, no embryo 
develops in the eggs of Fundulus, but that the same degree of toxicity 
is reached in an m/8 solution of Ca(NO,),, thus showing the mag- 
nhesium salt to be less toxic than the calcium salt. On the other 
hand, as shown by Macowan (14), MgCl, is far the most toxic 
of the four chlorids employed in experiments on wheat; and in this 
respect the behavior of B. subtilis resembles that of Fundulus rather 
than that of the higher plants. 
Experiments with binary solutions 
The fact that the results obtained were in such striking general 
agreement with those of the investigators above mentioned on animals 
and higher plants was sufficient stimulus for further inquiry into the 
biochemistry of ammonification. It was deemed of interest, therefore, 
to see if antagonism between salts holds as well for bacteria as it does 
for the higher forms of life, with the end in view of ascertaining whether 
’ balanced solutions are necessary for bacteria, and whether solutions 
_ balanced for the other forms of life investigated will prove the same 
eet we A ee 
oh 
for bacteria. The remainder of this paper will deal with the an- 
tagonistic effects of one salt on another in binary solutions, while 
