1921] 
WEBB—GERMINATION OF SPORES OF CERTAIN FUNGI 339 
(11) The expanded range of germination under conditions 
of active alkalinity in such solutions as beet decoction and 
‘‘water HCl or KOH" might appear on first glance to be corre- 
lated with buffer effects. Buffer action in these solutions is 
feebly present in the beet decoction and totally absent in the 
water. This is, no doubt, an important factor, but the experi- 
mental results here obtained seem hardly to justify an explanation 
entirely on such a basis. The fact that germinating spores of 
B. cinerea produce changes in reaction in the beet decoction 
medium and not in the ‘‘water HCl or KOH” is very striking. 
(12) Various additions of sugar beet decoction to solutions 
of mannite pronouncedly stimulate germination with the two 
organisms under experimentation, namely, A. niger and B. cinerea. 
The percentages and the range of germination approach those 
offered by beet decoction alone, and no manifested resemblance 
to those furnished by the mannite alone is recognizable. 
(13) It would seem, therefore, that germination in the beet 
decoction is stimulated by some special substance or peculiar 
set of conditions, either or both of which are totally or partially 
absent in the synthetic culture media. 
(14) With increase in length of intervals of incubation, the 
relations of germination to hydrogen-ion concentration, other 
than a general increase in magnitude of all germination quantities 
and a frequent expansion of inhibitory limits, remain practically 
the same. 
(15) The curves of germination for any organism are practically 
identical, whether incubated at a temperature representing a 
provisional optimum or at 4-5? C. above or below such an 
optimum. Germination often occurs feebly in cultures possess- 
ing a hydrogen-ion concentration closely approaching that of 
inhibition, and, if differences are manifested in the favorable 
ranges the tendency is for germination to occur over the widest 
range at the optimum temperature. 
(16) The data here developed and presented, it is felt, are 
sufficient to change materially the previously prevailing view 
concerning the relation of germination of fungous spores to acid 
and alkaline media, as well as to be of fundamental importance 
in any future study of fungicides or spray mixtures. 
