116 BOTANICAL GAZETTE [aucust 
Malonic acid (table 56) is dissociated to the extent of 82.3 
per cent.when one gram equivalent is dissolved in 1024 liters, so 
that at the concentration one gram equivalent in 3200 (the con- 
centration in which the lupines live) the acid is highly disso 
ciated though probably not completely. 3 
Succinnic acid is a much weaker acid. It is dissociated only 
30.82 per cent.when one gram equivalent is contained in ne : 
liters (Ostwald). Table 56 shows that some of the seedlings 
survive when one gram equivalent of the acid is contained oe 
1600 liters. | 
Fumaric acid (table 58) allows the beans to survive when 0% 
gram equivalent is contained in 6400 liters, whereas maleic acid 
(table 59) permits them to live when one gram equivalent is present 
in 3200 liters. As maleic acid at the dilution 1024 is dissociated” 
98.2 per cent. and fumaric only 78.5 per cent., we should expect : 
the latter to be less poisonous than the former, if the i a 
action be due to the hydrogen ions alone. That the opposite = 
apparently takes place seems to show that the anions of fume 
acid exert a toxic action at this high state of dilution. whet ' 
this is true or not can only be definitely settled by investigatiNg : 
the action of a salt of the acid the cathion of which has no® 
effect. We do not place much reliance on the results Sti 
from these two acids as it is questionable whether the substance 
were perfectly pure. i 
60. MALIC ACID. 
(Begun January 28, 6 P.M.; closed January 29, 9 A.M.) 
=—S—= a 
Concentration ‘ 
8M. equiv. per liter Length Remarks 
pine 
1805 18.5" flabby, dead 
oe 
se we 17.5 oe ““ 
szv0 a76 alive 
Foe ew. 20.5 oe “ 
waton 25.0 “sé ‘“ 
Ge 
In a solution of malic acid (table 60) the seedlings 7 
en one gram equivalent is present in 3200 liters. This® 
“See Ostwald, Zeitschr. . physik, Chem., 3: 380. | 
wh 
