2 
]\Iycologia 
Hymenochaete riibiginosa is a common saprophyte on decor- 
ticated chestnut in the vicinity of Ithaca, N. Y., and is also found 
more rarely on decorticated oak. The brown, resupinate or dim- 
idiate fruit bodies (Figs, i, 3), rarely over four or five centi- 
meters in diameter, are usually to be found where oak and chest- 
nut timber lies on the ground in the forest. Chestnut-rail fences 
which extend into the deep shade of the woods present an ideal 
place for its collection and almost invariably the lowest rail, par- 
tially immersed in leaf mold, is infested with the fungus. Where 
the rail is oblique to the surface of the ground and one end is 
imbedded in the humus, thereby insuring a sufficient supply of 
moisture, the fruit bodies may be entirely resupinate and reflexed. 
On fallen trunks they usually become dimidiate and often hollow- 
ungulate, the pilei imbricated, irregularly united and sharply obli- 
que to the substratum. When mature, the shelving pilei are 
smooth above, except for the pubescent margin, and exhibit fine 
concentric lines on their upper surface. These are not the result of 
perennial growth, since the fruit bodies are annual, but rather of 
fluctuations in seasonal growth brought about by varying amounts 
of moisture. The fruiting surface, or hymenium, of the pilei is 
glabrous at maturity except at the margin. When viewed with a 
pocket lens of ten diameters, it is seen to be covered with many 
brown setae which project upward from the grayish hymenium. 
It is due to this character that Leveille^® first separated such 
forms from the genus Stereum. 
Development of the Fruit Bodies . — As already noted, the fruit 
bodies make their appearance on decorticated wood. Even in 
collecting several hundred specimens at periods extending over 
two years, no exceptions were found to the above rule. The fruit 
bodies rarely appear on wood in an advanced stage of disintegra- 
tion. A few cases were observed where the wood was badly de- 
cayed to a depth of a centimeter under the fruit bodies due to at- 
tacks 'Of this or other fungi. In such cases, however, the fruit 
bodies were always connected with the firm, hard wood In the core 
of the log. They are never formed from mycelium in wood 
which has lost its firmness or exhibits advanced stages of decay. 
The first evidence of the formation of fruit bodies is the ap- 
pearance of small, brown, mycelial wefts on the surface of the 
