106 
Journal of Mycology 
[Vol. 10 
The size of the collar surrounding the pore was carefully 
noted since Fischer 1 2 stated that the absence of a collar is one of 
the chief characteristic marks of D. phalloidea var. campanulata. 
The large size of the collar is also mentioned by Morgan" in his 
description of D. duplicata. As a matter of fact this character 
is extremely variable. A complete series of forms was found, 
varying from those with absolutely no band surrounding the pore 
and with the gleba coming to its very margin, to those having a 
band 1.2 cm. wide from the edge of the pore to the free edge of 
the collar. The size of the pore varied from 0.3 cm. in diam¬ 
eter in No. 20 to 1.2 cm. in No. 13. Here again there was no 
correlation between the size of the collar and other characteris¬ 
tics, nor did the size of the collar depend upon the size of the 
pore. No. 6 has a broad, low pileus and no collar, while No. 3, 
also without the collar, has a relatively tall and conical pileus. 
No. 16 has the slightest trace of a collar. No. 1, which has the 
largest collar, has a large pileus with about an average relation 
between the height and diameter of the base. 
The presence of a bit of gelatinous material, or a fragment 
of the volva on the apex of the pileus was mentioned by Cragin 1 
in his description of P. collaris. It was found in one case where 
several plants were collected from the same mycelium that a com¬ 
plete series of variations in this character existed. This series of 
specimens varied from one with an open pore to one in which 
the membrane of the volva had ruptured at the side and one- 
third of the peridium was borne on the apex of the pileus. These 
specimens were gathered near the close of the season. It was 
afterwards noted that when the cool weather began to retard the 
development of the plants a greatly increased proportion of the 
specimens was found with part of the peridium covering the 
pileus. 
There is no other part of the whole plant that shows as great 
variation in both size and structure as does the veil. The veil 
of a given specimen may vary with the age of the specimen when 
collected, or with the surrounding conditions. It was often ob¬ 
served that the veil expanded after the stipe had fully elongated. 
In other specimens the expansion of the veil was more rapid 
than the elongation of the stipe. In such cases the veil protruded 
from between the pileus and the volva as a large fold, which 
later straightens out and hangs free when the stipe is fully ex¬ 
tended. When a specimen had been exposed to a dry atmosphere 
for a short time the veil became much shrunken. The measure¬ 
ments given in the table were taken from specimens gathered at 
about ten o’clock in the forenoon. Care was taken to measure the 
length of the veil when it was most fully expanded. While the 
1 Loc. cit. 
2 Loc. cit. 
1 Loc. cit. 
