1908] ATKINSON—POLYPORUS LUCIDUS 331 
as verrucose in several species (Ganoderma tsugae Murrill, G. lucidum 
[Leys.] Karsten, G. curtisii [Berk.] Murrill, and others). 
In studying the spores of these species I have been surprised to 
find that they are not echinulate or roughened. The spore wall is 
smooth, that is, there are no elevated or projecting portions of the 
surface. But the spores have a very peculiar structure, which re- 
Fic. 5.—Ganoderma subperforatum Atkinson, from Ohio (natural size). 
quires very careful examination to interpret properly, and sometimes 
the use of the oil immersion lens is necessary to resolve clearly the 
characteristic structure of the wall. On a first examination of the 
‘pores with the dry objective, they appear warty or roughened ; 
ut the appearance is so peculiar that I was not content with-this 
(efinition and sought to determine more accurately the nature of the 
Peculiar structure. When the upper or lower surface of the spore is 
™ the focal plane, the wall of the spore presents the appearance of 
