1915] CURRENT LITERATURE 417 
Le RENARD attempts to establish as a measure of the antitoxic action 
of a substance the “antitoxic coefficient,” which is defined as the ratio 
between the number of liters containing a gram-molecule of the antitoxic 
substance in centinormal solution (that is, 100 in the case of monovalent sub- 
stances) and the number of liters in which a gram-molecule of the toxic sub- 
Stance is dissolved at the limit concentration. The propositions which the 
author derives from the ratio thus defined, and with whose derivation the 
first part of the paper is concerned, all follow from the arithmetical relations 
of the quantities involved in the definition, and like the antitoxic coefficient 
itself have no physiological significance. In his experiments LE RENARD 
studied the antagonistic action with reference to Penicillium glaucum of 
formates, acetates, sulphates, and nitrates of potassium, ammonium, and 
magnesium, and the phosphates of potassium and ammonium in combination 
with salts (mostly chlorides and nitrates) of the heavy metals. The antitoxic 
solutions were used in concentrations ranging in a geometrical progression with 
a ratio of 1/10, usually from N 107? to N 1075. The toxic substance was gen- 
erally used in one or two arbitrarily chosen concentrations. The results show 
an unusual regularity for biological data. The chief conclusion of the author 
is that the resistance of Penicillium to poisons varies according to the nutri- 
tive medium in one of the following ways: (1) the resistance varies, in a simple 
Tatio, inversely as the concentration of the antitoxic substance; (2) the resist- 
ance passes a maximum at a comparatively low degree of concentration of the 
antitoxic substance; or (3) the resistance is not modified. The first part of 
this conclusion seems scarcely to be borne out by the data, for in nearly all 
cases where different concentrations of the toxic substances were used the 
quantities endured by the fungus fell with a diminution of the concentration 
of the antitoxic substances. It is probable, furthermore, that the use of a 
greater number of aap eis = praniies eeerae between them would 
have led the author to modify his conclusion lati said to exist 
between the concentration of an antitoxic substance and its effect on the toxicity 
of another substance. The recent work of Sziics“ has clearly shown that the 
antagonistic ionic effects do not follow any such simple law of proportionality. 
The antagonism between the nitrates of calcium, magnesium, and potas- 
sium on the one hand, and nitrates of copper, lead, zinc, aluminum, and nickel 
on the other hand, with reference to the spores of Glomerella cingulata, has 
been investigated by Hawkins. The technique employed was similar to 
3 LE Renarp, A., Influence du milieu sur - atsistance du Pénicille crustacé aux 
substances ager Ann. Sci. Nat. Bot 277-336. 1912 
4 Sztcs, J., Experimentelle ee ed zu einer Theorie ut antagonistischen 
liaise Jahrb. Wiss. Bot. 51:85-142. 1913 (rev. in Bor. Gaz. 56:85 
1913). 
*s Hawkins, L. A., The influence of calcium, magnesium, and potassium nitrates 
upon the txt of certain heavy metals toward fungus spores. Physiol. Researches 
1257-02. 
