1913] CURRENT LITERATURE 511 
JAVILLIER™ negatived this conclusion and attributed the lack of spore-formation 
in the absence of iron to the deleterious effect of zinc in RAULIN’S solution, for 
they found that when both zinc and iron were absent spores were produced by 
the fungus. Meanwhile, BERTRAND” reported experiments which seemed to 
indicate that manganese played a special part in the spore-production of 
Aspergillus niger. 
The question of the influence of various elements on the spore-production 
of molds has now been further investigated by Sauton.% He finds that if A. 
miger is grown on: RAvtin’s solution to which iron in the form of ferric am- 
monium citrate has been added, no spores are produced, thus strengthening 
his conclusion that iron plays no special part in the spore-production of that 
fungus, If, however, iron sulphate is added to the solution, spores are pro- 
duced. The difference in behavior of the two salts may be ascribed to the 
absence of manganese in the one and its presence in the other. The author 
finds, however, that in a solution without zinc, spores are produced in the 
absence of any detectable traces of iron and manganese, and concludes, there- 
fore, that if these elements are necessary for A. niger, the requisite quantities 
are limited to such minute traces that they cannot be detected chemically. He 
finds that in this respect A. fumigatus is a more favorable object of experimen- 
tation. If of the two elements in question manganese alone is present in the 
culture solution, this fungus produces spores after 15 days, while with iron also 
Present spores are produced on the third day. If manganese is absent no spores 
are formed. It appears, therefore, that for this mold both iron and manganese 
are Necessary for spore-production. The influence of some of the other elements 
of RavLIn’s solution on spore-production was also determined. In the a sence 
of sulphur A. niger grows poorly but nevertheless produces spores. A. fumi- 
gatus, however, does not produce spores in the absence of that element. No 
Spores are produced by either mold in the absence of potassium, but the addition 
or withdrawal of caesium and rubidium are without influence. In the absence 
of phosphorus no spores are formed, but it does not seem to be possible to 
exclude magnesium to such an extent as to inhibit spore-formation. 
It is likely that this work would lead to more definite results if it were 
Separated from the problem of the toxicity of zinc, which although placed by 
Ravtin among the elements of his culture solution is not a substance necessary 
in the metabolism of plants. 
BERTRAND and 
4 Riese 941 + the action 
T 
JAVALLIDN b r 

* Rev. Bor. Gaz. 55:88. 1913. 22 Rev. Bot. Gaz. 55:89. 1913. ; 
*3 SAUTON, B., Sur la sporulation de Aspergillus niger et de l Asper gillus fumiga- 
fus. Ann. Inst. Pasteur 27: 328-335. 1913. : 
* Bertranp, Dr., et Javizz1ER, M., Action combiné du manganése et du zine sur 
le développment et la composition minérale de l’Aspergillus niger. Ann. Inst. 
Pasteur 26: 515-521. 1912. 
