AN ENEMY OF THE WESTERN RED CEDAR 
William A. Murrill 
(With Plate 122, Containing 2 Figures) 
The species described below was first sent to me from Idaho 
by Mr. Weir. Since the description was drawn, Mr. Weir wrote 
me under date of December 17, 1913, as follows: 
During the past season, the species has been abundantly col- 
lected throughout northern Idaho and Washington. It has been 
found to be of far greater importance in its relation to the decay 
of the western red cedar than my previous observations showed. 
Not only is it the principal fungus concerned in the basal decay 
of the living tree, but it continues the destruction of the heart- 
wood and later of the sapwood after the tree has fallen and may 
extend along the entire tree, even attacking the bark. The 
chemical action of the mycelium on the wood results in a separa- 
tion of the annual layers in the initial stages of decay, later 
developing a brown, friable rot quite characteristic and easily 
recognized. The damage caused by the fungus in the western 
red cedar is great enough to be made a special project for the 
coming field season. 
Fomitiporia Weirii sp. nov. 
Broadly effused, often extending many feet along the trunk, 
irregular, adnate, rather soft, of light weight, flexible when young, 
3-10 mm. thick, margin rather thick, adnate or slightly 'seceding, 
undulate, lobed, or irregular, broadly sterile, ferruginous to 
fulvous, velvety-tomentose ; context conspicuous, fulvous, punky, 
soft and flexible; hymenium plane or conformed to the sub- 
stratum, fulvous-umbrinous, often with an avellaneous tint; tubes 
indistinctly 2-3 times stratified in older specimens, 2-4 mm. long 
each season, avellaneous within; mouths angular, stuffed when 
young, minute, about 6 to a mm., edges thin, entire; spores 
ellipsoid, smooth, hyaline, 5 X 3/*; hvphae ferruginous ; cystidia 
conic, tapering to a sharp point, not ventricose at the base, 
fulvous, filled with contents, sometimes strongly curved, 35-50 X 
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