Feb. io, 1925 Root Rot of Grapevine Caused by Clitocybe Tabescens 355 
Pat. (30, p. 248) should be confused 
with Curtis’s name, for they represent 
entirely different species. 
In 1883, Schulzer von Muggenburg 
(44, V • 256) described as a new species 
a plant occurring in Hungary, Poland, 
and Transylvania, which he had had 
under observation for several years and 
regarded as an exannulate form of 
Agaricus (Armiliaria) melleus, naming 
it Agaricus ( Collybia) inarmillatus. 
This was regarded as a synonym of 
Clitocybe tabescens by Bresadola (6). 
In the same year Morgan (27) 
described from Ohio a plant which 
closely resembled Agaricus (Armillaria) 
melleus , but which lacked an annulus. 
This he called Agaricus monadelphus, 
placing it under Clitocybe. 
In 1892 Peck (32, p. 180-181) pub¬ 
lished Miss Banning’s description of 
Clitocybe aquatica, based upon speci¬ 
mens from Maryland. A year later 
Peck (33, p. 134) under his description 
of Armillaria mellea, mentions the 
receipt from Brooklyn, N. Y., and 
Washington, D. C., of a densely 
caespitose, slender-stemmed form with 
no annulus, which he called var. 
exannulata. The following remark by 
him is of interest: “It is scarcely dis¬ 
tinguishable from Clitocybe aquatica 
Banning, and Clitocybe monadelpha 
Morg., which, I suspect, will yet have 
to be referred to this species. Accord¬ 
ing to Quelet, Clitocybe socialis DC., 
and Agaricus gymnopodius Bull, also 
belong here.” 
In 1895 Peck (34, p. 265) described 
Armillaria mellea var. exannulata in 
greater detail. In 1898 he reported 
for the first time the occurrence of 
Clitocybe monadelpha in New York 
(35, p. 284) and described and illus¬ 
trated the species (35, p. 302-303, 
pi. 51, figs. 1 to 5). In his report on 
the edible fungi of New York in 1900, 
Peck (36) reproduced the same de¬ 
scription of Clitocybe monadelpha, the 
illustrations being changed somewhat. 
In 1900 appeared Bresadola’s work 
(6), in which he pointed out that the 
plant we have known best in the United 
States as Clitocybe monadelpha is but 
a synonym of Clitocybe tabescens of 
Europe. It is generally conceded by 
most American mycologists familiar 
with this plant that Bresadola was 
correct in considering the American 
plant to be the same as the European. 
Boudier’s excellent illustration, ap¬ 
pearing as Plate 61 (51a) in his “leones 
Mycologicae ou Iconographie des 
Champignons de France” and repro¬ 
duced with slight modification as 
Plate 197 of Bresadola’s work, is re¬ 
produced here as Plate 6. It is typical 
of our plants. 
In his paper on a rhizomorphic root 
rot of fruit trees in Oklahoma caused 
by a caespitose species of Clitocybe, 
Wilcox (58) states that this species of 
Clitocybe is closely related to C. mona¬ 
delpha Morgan and to Armillaria mel¬ 
lea exannulata Peck, but he describes 
it as a new species, C. parasitica, since 
he believed that it differed from these 
two species in certain morphological 
characters and in its parasitic habit of 
growth. 
Unfortunately, the writer has not 
been able to see the type of Wilcox’s 
species. Specimens do not occur 
either at the Missouri Botanical 
Garden, where he spent a few weeks 
in examination of the literature, or 
at the Oklahoma Agricultural and 
Mechanical College, where, if any were 
deposited, they probably were de¬ 
stroyed in the 1914 fire which con¬ 
sumed the herbarium and all records 
pertaining thereto. 
Almost the only points in which 
Wilcox’s description of his species 
differs from Morgan’s are these: In 
Wilcox’s plant the pileus is roughened 
with small scales from the first instead 
of being at first glabrous and then 
scaly; the stipes are never twisted, and 
it “is always parasitic in habit.” 
According to the observations of the 
writer on the plants in both Missouri 
and Florida, Wilcox’s morphological 
distinctions are based on rather vari¬ 
able characters. It is obvious that 
fungi never can be stereotyped crea¬ 
tions and that mycologists must 
allow a certain amount of latitude in 
the species concept, which, in this 
case at least, is but arbitrarily defined. 
Citing a statement in one of Morgan’s 
letters to him, written in 1901, that 
C. monadelpha is never a parasite, 
Wilcox reports (58, p. 18) that “our 
species is always parasitic in habit,” 
and at the bottom of the same page 
further states that “the species grows 
in dense clusters from the crowns of 
living trees and the stumps of dead 
trees but is strictly a parasitic form in 
both cases.” In his summary on page 
22 he says: “The same fungus is a 
common parasitic and saprophytic 
form on four species of oak in Okla¬ 
homa.” It is obvious, therefore, that 
neither the distinctions made by 
Wilcox in the morphological characters 
nor those in the habit of growth of 
these two fungi hold good. 
Wilcox regarded the Oklahoma form 
as distinct from Peck’s Armillaria 
mella exannulata because the plants 
