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in which the fruiting body is predominantly cup-shaped or dis- 
coid with the hymenium lining the upper surface, although ther 
are many exceptions to this general rule. In all, however, - 
hymenium is freely exposed at maturit y. 
“As pointed out by Boudier, the cup fungi may be divided 
into two very natural groups, the basis of division being the 
method of the dehiscence of the ascus. The first, which is called 
y him the Operculae, may be recognized by the fact that the 
ascus opens at the apex by a circular lid, which is known as the 
operculum, It is og group which is referred to under the name 
of ‘fleshy cup-fungi.’ 
“The second group is known as the Inoperculae since the ascus 
does not open by means of an operculum but by a simple pore 
which is formed by the rupture of the ascus. Although the pres- 
ence of the operculum was noted first by Crouan, it was Boudier 
who in 1879 first called attention to its significance as a basis of 
classification. 
‘While at first thought this might seem an obscure character 
it is really very distinct and easily recognizable with a little ex- 
perience. There are, however, a few exceptions to the rule. 
he fete cup-fungi as considered here include most of the 
large conspicuous species as well as many of the smaller ones, 
some of which are less than a millimeter in diameter. Among 
