758 
8 
We thus observe that the addition of ino SS mol. coppersulfate 
considerably enhances the weight of mould after 9 days; it is more 
than 70 milligr. greater than that obtained without addition of copper. 
Already before’) I explained that the non-formation of spores 
commonly coincides with the accumulation of glycogen in the mould 
and with a high plastic aequivalent of the carbon. 
This we find confirmed here, compare for instance Nrs. 1, 2, 3. 4. 
The values of the then following numbers are not very exact. 
That they are notwithstanding mentioned is to make clear that even 
considerable copper concentrations (N°. 9) do not change the character 
of the metabolism. The decrease in quickness of the assimilation 
of glucose is very obviously caused even by slight quantities of copper. 
Whether the greater mould production may be called favourable is 
doubtful, the sporeforming being retarded. 
| 4. Action of manganese. 
BerRrRAND and JAvILLIER®) found that addition of manganese enhances 
the weight of mould whilst it was also stated that this element is 
fixed in the organism. It also proved necessary for the spore forming ®). 
By a very minute examination BeRTRAND succeeded in showing that 
manganese made the weight of mould 
ren additi of ————— 
even addition 10000000000 
rise considerably. As will be seen from Table V the addition 
of manganese had especially brought about changes in the velocity 
of the glucose assimilation. For the rest, my experiments with manganese 
have confirmed those of BERTRAND and JAVILLIER. 
The composition of the nutrient liquid was: 
very pure distilled water in which dissolved: 
0.15 °/, ammoniumnitrate 
0.1 ,, potassium chloride 
0.1 ,, magnesiumsulfate (crystallised) 
0.05 ,, calciumnitrate (free from water) 
0.05 ,, ammoniumfosfate 
0.05 ,, fosforic acid (crystallised) 
2.— ,, glucose 
DH. J. WATERMAN, Folia Microbiologica I. (1912) p. 422. 
2) BERTRAND et JAVILLIER. Influence du manganése sur le développement de 
Aspergillus niger. G. r. 152 (1911) p. 225; Ann. de l'Institut Pasteur T. 26 (1912) 
25 Avril p. 241. 
5) BerTRAND. Extraordinaire sensibilité de |’Aspergillus niger vis à vis du 
manganèse. C, r. 154 (1912) p. 616, 
