24 ANDERSON: DASYSCYPHA RESINARIA CAUSING 
mon larch canker-producing fungus of Europe, which were familiar 
to the writer in their living and natural condition. The canker 
swellings and deformations had much the same appearance as 
those caused by D. calycina, especially in the profuse resin exuda- 
tion and flow from the wound. 
The external character of the canker-swellings and the pres- 
ence of the ascomata, which were found only on the affected parts, 
led me to believe that the fungus, if not D. calycina, was a para- 
sitic one, closely related to the larch canker, Dasyscypha, of 
Europe. 
Material of the affected stems and fungus was collected at the 
time, which has since been worked up. The more important char- 
acters of the fungus and its effect on the stems are given in this 
paper. 
THE Funcus 
The ascomata are found only on the bark of the canker-swell- 
ings and deformations on living trees or on the similar swellings 
on branches and stems which have recently been killed by the 
cankers. The fungus is not present on the bark of any other 
part of the tree. 
The ascomata are stipitate when mature, but sessile in their de- 
veloping condition (fig. 3, a). The cups of immature and mature 
ones are approximately of the same diameter—one-half to one mil- 
limeter across. The stipe varies from one-fourth to one millimeter 
in length. The whole ascoma is covered over with pilear hairs 
(fig. 3), which are longer and more abundant on the cup, espe- 
cially around the disc, than on the stipe (figs. ¢ and 6). 
The hairs, which surround the disc, project upwards perpen- 
dicularly to the disc when the ascoma is wet or moistened, but 
when in a dry condition the hairs of the fringe are turned inwards 
and almost cover and exclude the disc from view. The reason 
for this movement will be explained later in the paper. The disc 
is slightly orange colored, seen best in younger ascomata, soon 
after they have opened. The stipe and surface of cups of mature 
ascomata are grayish, becoming whitish and more easily seen on 
the bark, when in a dry condition. The ascomata, although of a 
leathery consistency, become brittle and easily drop off when dry- 
Sections of the ascoma shows it to correspond, in its structural 
