394 BOTANICAL GAZETTE [DECEMBER 
CuSO,, which effectually inhibited germination in the form used 
by the writer, contains about 0.1 per cent. CuSQ,.. DeSeynes 
(’95) reports growing cultures of Penicillium glaucum, gotten from 
different sources, in solutions containing 2 to 9.5 per cent. 
CuSO,. Cultures grown on the stronger concentrations bore red 
spores. Pfeffer (81) reports finding Penicillium growing ona 
concentrated solution of CuSO,. Manasein (fide Loew 93) 
finds from his experiments that this salt must be present in a 
.25 per cent. concentration before it has any appreciable effect on 
this fungus. Others might be quoted, but sufficient has been 
said to indicate the possibilities yet to be investigated of the 
acclimatization of fungi (and other plants) to chemical agents 
(Davenport and Neal, ’96). 
Zinc sulfate—Inasmuch as zinc chloride is used very exten- 
sively for impregnating railroad ties to prevent attacks of wood- 
destroying fungi (Roth, ’95), it was a surprise to find it having 
so low a toxic value, particularly when it is recalled that one of 
the molds tested, Penicillium, is one of the enemies of the wooden 
ties (Ward, ’98). Koch (’81) finds the chlorid and the sulfate 
to have practically the same disinfecting power. Towards 
Aspergillus we may say that zinc is non-toxic, the spores surviv- 
4 E m a 2n 
ing an immersion of 48 hours in a on (27 per cent. anhydrous 
ZnSO,) concentration. In a - concentration (7 per cent.) 25 
per cent. of the spores germinated and grew slowly. The 
mycelium produced was very irregular and closely septate. 
Strychnin sulfate, CoH UNO HGSO:. This alkaloid, the 
only one experimented upon, was dissolved in the slightly acid 
beet infusion until a saturated solution was obtained. This was 
found to have a content of 4.31 per cent. strychnin sulfate. This 
| solu- 
s é 2 
in terms of a normal solution would be about = a norma 
tion of this substance requiring over 30 per cent. on account of 
its very large and heavy molecule. 
Sterigmatocystis grew and fruited normally i 
solution, although germination and early growth were fr 
n this saturated 
etarded. 
