760 
ganese, which proved more favourabie than that of each of these 
elements separately. 
In his last communication JAVILLIER *) mentioned that the constant 
relation between the assimilation of sugar and the production of 
mould, which is nearly 3:1, sometimes became 8:1 by leaving out 
zine, that is to say, addition of zine should allow the organism to 
use less food; besides, the assimilation of nitrogen and of the other 
anorganie elements changed according as zine was added or not. 
Hitherto I have not been able to confirm JAVvILLIER’s results. 
Addition of zine caused but little change in the metabolism of 
the carbon, but again the velocity of the glucose assimilation was 
modified. 
seer l. ZuCl 
en 
nme ante Ze: 
p. L. caused a distinct, albeit slight increase of the plastic aequiva- 
lent of the carbon, but it was accompanied by non-formation of 
Addition of stronger zine concentration : 
spores. 
In many respects, thus, the action of zine resembles that of cop- 
per. As with this element the addition of slight quantities of zine, 
which exerts no perceptible influence on the production of spores, 
causes hardly any change in the weight of mould. 
he 7 7 
So, nutrient solutions containing 100.000.000 * 10.000.000 and 
7 . 
1.000.000 or mol. ZnS 0 AG: por, produced after: four days 
respectively 407, 410 and 417 milligrs. of dry material, whilst analogous 
experiments, without addition of zine, produced 406 and 408 milligrs. 
The fact that stronger concentrations of zinc check the forming 
of spores (see above) which had also been observed by Sauron *) and 
JAVILLIER ®), BERTRAND*) tries to explain by the relation existing 
between the quantity of manganese present on one side, and the 
produced mould on the other. 
Thus BerrRAND says: “Lorsque au milieu nutritif on n’ajoute ni fer, 
ni zine, ou seulement du fer ou du zine, les mycéliums qui pren- 
nent naissance sont si réduits que le rapport du manganese, introduit 
volontairement on non, au poids de matière organique formée, peut 
1) Javittier, Influence du zinc sur la consommation par /’ Aspergillus niger. 
de ses aliments hydrocarbonés, azotés et minéraux, CG. r. 155 (1912) p. 190. 
2) B. Sauton, C. r. 151 (1911) p. 241. 
8) M. JAvILLIER et B. SAUToN, Cr. 153 (1911) p. 1177. 
4) G. BerrRAND, Ce r. 154 (1912) p. 381, 
