II4 BOTANICAL GAZETTE [AucusT : 
between CaCl, and KCl. Osternovrt (20) obtained a similar curve — 
for the antagonism between the same two salts in his experiments — 
on wheat. It is particularly interesting to note that both for wheat — 
and for bacteria the maximum point of the curve is at the combina- — 
tion of roo°* KCl solution and 5°° CaCl, solution, notwithstanding — 
the wide difference between the materials employed in the two cases, — 
and further despite the fact that the Ca ions are most toxic for B. 
subtilis and least toxic for the wheat. 
Again we find the strong antagonism above obtained is in strik- 
ing accord with the results of Lorn in similar experiments on animals, — 
both as to development (7) and as to muscular contraction (6). j 
SERIES VI. SODIUM CHLORID vs. MAGNESIUM CHLORID 
In this series the experiment was arranged and carried out in the — 
same manner as the one preceding, except that the salts used were — 
different. The ammonia formed at the end of the period of incuba- 
tion was determined with the following results: 
TABLE VI 
ALL QUANTITIES GIVEN REFER TO CUBIC CENTIMETERS OF o. 35 m SOLUTIONS 
Culture solution | Corresponding | Milligrams of N 
POG NO pra K 22.36 
too NaCl } 
5 MgCl, § *7-"°7°* a 23.75 
too NaCl 
pa, Vo eens I 28.67 
too NaCl 
25 MgCl, Sete oe H 24.56 
too NaCl 
50 MgCl, BT as is 18.67 
too NaCl 
100 MgCl ae et oe F 10.49 
50 NaCl 
100 MgCl, Sian ce Se er oe ee ee ) E 4 84 
25 NaCl | , 
MgCl, Sirk de pe | D 3.80 
to NaCl 
10d MgOly hosts se | Cc 3-54 
5 NaCl 
‘oe gCl, Royce eine ere B 3-36 
500 JAMULS 6 aie A 2.13 
