The Biology of Polyporus Pargamenus Fries 67 
put out at one end of the spore and very shortly after this 
another one is put out from the other end. Occasionally 
germ tubes are put out simultaneously from both ends, but 
in general one seems to precede the other. In some instances, 
however, the one germ tube makes considerable growth before 
the spore puts out one from the other end. Germination 
from the side of the spore is of rare occurrence. 
No instances were observed in which more than two germ 
tubes were put forth from a single spore. The spores were 
not observed to become vacuolate before germination, 
although spores which failed to germinate became 2-vacuolate 
and more or less distorted after lying in the hanging drop 
culture for a few days. After several days they were 
found to have collapsed. Even after several weeks the col- 
lapsed spores could be clearly detected in the drop. Before 
putting forth germ tubes the spores swelled up to less than 
twice their original size. The germ tubes are nearly as 
wide as the spores and germination seems to be merely a 
gradually tapering prolongation of the spore wall. After 
a few days’ growth it was usually impossible to distinguish 
the position of the original spore wall in the mycelium. In 
many instances, especially in slowly growing plants, small 
globular inflations or cysts were noticed on the mycelium, 
some being lateral and others terminal (Plate VIII, h; and 
Plate IX, 2,3, 4, and 5). These local enlargements of the 
hyphe evidently were peculiar to this particular fungus for 
they were observed to occur after forty hours’ growth in a 
number of hanging drop cultures in practically every medium 
used in which germination was secured. No such abnor- 
malty, however, could be detected in any of the numerous 
cultures made on solid media. 
It was clearly evident that these peculiar cyst-lke bodies 
were not reproductive bodies. It is the writer’s opinion that 
they occur solely as a result of the physiological response of 
the mycelium to the excessively unnatural conditions of the 
nutrient medium for its growth. The mycelium invariably 
developed large numbers of these globular enlargements in 
the younger stages of its growth, but ceased to develop them 
