214 Transactions British Mycological Soctety. 
sterquilinus can only germinate in the presence of bacteria. In 
rg11, A. H. R. Buller and S. G. Churchward, working in the 
Botanical Department of the University of Manitoba, carried 
out a series of experiments upon the conditions of germination 
for the spores of C. sterquilinus; and they found that Miss 
Baden’s conclusion was incorrect, for in their experiments 80 to 
go per cent. of the spores germinated in perfectly sterile hanging 
‘drops of various media*. I herewith state that my investiga- 
tions entirely confirm the work of Buller and Churchward, for 
the spores of C. sterquilinus used in my cultures, when ger- 
minating, never came into contact with any bacteria. Were 
the presence of bacteria a necessary condition for the germina- 
tion of the spores of C. sterquilinus, the isolation of monosporous 
mycelia could not have been accomplished by the simple 
methods which I actually employed. In none of the nine species 
of Coprinus with which I worked, is the presence of bacteria 
a necessary condition for the germination of the spores. 
Miss E. M. Wakefield made monosporous cultures of Schizo- 
phyllum commune and of Stereum purpureum and came to the 
conclusion that the chief factor making for sterility or fertility 
in her cultures was individual mycelial peculiarity, some mycelia 
fruiting readily and others refusing to fruit under any condi- 
tions. According to Kniep, the explanation of Miss Wakefield’s 
results is as follows. Schizophyllum commune is a heterothallic 
species which fruits readily when the mycelium is diploid and 
has clamp-connections but more or less reluctantly when the 
mycelium is haploid and has no clamp-connections. On pairing 
the 14 monosporous mycelia which he isolated, he found that 
some pairs yielded clamp-connections and fruit-bodies and 
others not. In my work on Coprinus, I did not obtain a hetero- 
thallic species which fruited in artificial culture. However, it 
is remarkable that the homothallic species Coprinus niveus ex- 
hibited individual peculiarity in the fruiting of its monosporous 
mycelia, some mycelia having fruited readily, others having 
produced only fruit-body rudiments, and one having produced 
no rudiments at all. Yet even here, as already described, 
fruiting appeared to be stimulated by mixing two mycelia. 
* A. H.R. Buller and S. G. Churchward in an unpublished paper shown me 
by Professor Buller. The delay in publication has been caused by Churchward 
going overseas to the war. The details of the work will be given in Professor 
eee second volume of “‘ Researches on Fungi’ now in preparation for the 
Tess. 
} E. M. Wakefield, Die Bedingungen der Fruchtkérperbildung bei Hymeno- 
myceten, sowie das Auftreten fertiler und steriler Stamme bei» denselben, 
Naturw. Zeitschr. f. Forst- und Landwirtschaft, vi1, 1909, pp. 521-550. 
