1899] TOXIC EFFECT OF DELETERIOUS AGENTS 321 
values of these anions, as nearly as could be determined with 
Aspergillus and GZdocephalum, were as follows: 
Monochloracetic - - - —CH,CICOO, x 
Dichloracetic - - - ._ CHC], Coo; aT 
| Trichloracetic - 3 . ~ Sa os ar 
it s+ e+ 
Here the toxic values, although not high, are in the expected 
order, 
Let us next glance at the toxic properties of these acids in a 
practically completely ionized condition. Kahlenberg and True 
(96) found that with Lupinus 
6400 ‘ 
sowth. The same concentration of dichloracetic was evidently 
im the line, one plant being killed by it while the check survived. 
monochloracetic permitted 
q 
fygo ttichloracetic proved fatal. Ionization being practically com- 
Hee at this great dilution, we have to deal with ionic i and the 
Mons only. The toxic values of such solutions should be equal 
‘Uthat of HCl+ the value of the anion. This is exactly what 
ws find, Monochloracetic with its non-toxic anion has the same 
oa Value as HCl for Lupinus. The others are somewhat more 
‘ne: due doubtless to the influence of the anions, which are 
/ Pparently telatively more toxic towards the higher plants ge 
ards the molds, 
At the concentrations at which they are effective towards the 
°adadae we have an entirely different condition as reget 
_ ~~ ®8, as may be seen from the following: 
Monochloracetic inhibits at % and is 20 per cent. ionized. 
35 
Dichloracetic ‘i ” 
: “ 70 “c “ 
: Trichloracetic « a « ggg « “ 
2 Thi i : 22.8 i ; 
tion in the ionization {Ostwald ’89) is the key e 
* Planation of this apparent deviation from the rule referre 
above, 
“Stinet 
ee changes in the chemical and physical properties 
oniz A great increase in the toxic properties 
ed molecules, (2) A great increase in the 10nl? 
© introduction of Cl into the acetic radical np 2 a 
of tne 
of the 
ation of 
