[Vor. 8 
92 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
P M 
ec. ^ o AMn Oz 
A3 5 7 7 7 
Fig. 13. "Total action of extra- and intra- 
cellular amylase produced by Colletotrichum 
Gossypii grown in Czapek's solution of Pa 
4.5 ( ) Pa 7.0 (---), Pa 82 (..—-..), 
Pg 9.2 (==). 
of the fungus was not the 
same in the corresponding 
solutions. Thusfor Colleto- 
trichum it was Py 8.4 in 
Series 8, while under similar 
initial conditions the final 
reaction in the case of Fu- 
sarium was Pg 9. 
Sufficient data, in the ex- 
periments with Penicillium, 
have not been obtained to 
establish definite relations. 
However, natural Czapek's 
solution and Czapek's solu- 
tion having a reaction of 
Pa 3 were equally effective 
in producing an accumula- 
tion of amylase (fig. 14 and 
table vr). In these deter- 
minations, it was evident 
that the amount of amylase 
excreted into the culture 
solution and the amount 
formed in the mycelium was 
greater than in the other 
organisms in thecorrespond- 
ing culture solutions. 
A resume of the results 
with the three fungi showed 
that maximum amylase ac- 
cumulation was effected by 
Colletotrichum Gossypii and 
the least by Fusarium sp. 
Although the results as yet 
are not inclusive enough to 
warrant absolute state- 
ments, yet they indicate 
that H-ion concentration of 
the culture solution may be 
a factorinamylasesecretion. 
'The H-ion concentration at 
which maximum accumula- 
tion was produced varied 
