wat eae 



1891.] The Comparative Morphology of the Fungi. 1059 
ing these must be placed the angiocarpous forms, usually known 
under the name of Gasteromycetes. The author suggests that 
these last may have been derived either from the gymnocarpous 
forms through the hemiangiocarpous ones, or from the Proto- 
basidiomycetes through forms like Tulostoma. It is „worthy of 
note that development along parallel lines in the two great groups 
of fungi, in consequence of tke acquirement of a subterranean 
mode of life, should have brought about such striking similarity 
as is presented in the fruit bodies of the Tuberaceze and the 
Hymenogastree. 
The culture of a large number of Basidiomycetes has brought 
to light much that is new concerning their life-histories, and em- 
phasizes the fact that polymorphism is by no means a charac- 
teristic of the Ascomycetes alone, or even chiefly of that group, 
as has been thought since the Tulasnes’ classic researches. Bre- 
feld shows that in this respect there is little to choose between the 
two groups. Since the basidium is merely a modified conidio- 
phore, it might be expected that the Basidiomycetes would pro- 
duce, as accessory fruit forms, unmodified and still indefinite coni- 
diophores. And such is found to be the case witha number of 
forms, some of which have been already mentioned. In some 
Tremellineze, Polyporez, and other fornis, conidia have been for 
some time known. Another accessory fruit form which is 
always morphologically of strictly secondary value, although it 
often becomes of primary importance histologically, is the 
chlamydospore. These occur very frequently-in cultures of Basi- 
diomycetes, and in their simplest and commonest form are short 
joints cut off from the fungus threads, occurring in chains and 
constituting members of the old form-genus Oidium. They 
may often reproduce themselves indefinitely under suitable con- 
ditions without a hint of their true relationships; as in the case 
with the form known as Oidium lactis. Much less common are 
the more highly differentiated chlamydospores formed, like the 
Oidia, from joints of the mycelium, which occur in Nyctalis, 
Oligoporus, Fistulina, etc. These forms may be restricted to 
special parts of the fruit body, as to the hymenium in Nyctalis 
parasitica, or to the top of the pileus in N. astrophora. The 


