Chlamydospore-Forination in a Basidiomycete. 2 1 
Again, as regards their formation actually within the vessels of the 
wood, the only parallel cases seem to be the formation of “ oidia- 
chains ” (to he referred to below) in the case of Collybia longipes , 
and the innumerable conidia sometimes found in timber infected 
with Polyporus sulfureus. The latter were originally discovered by 
Hartig, 1 who at first thought that they belonged to some other 
species of fungus, but mentions them “ as he so constantly found 
them in company with the ordinary hyphse of P. sulfureus .” Later 
Seynes 2 published a monograph of this species and proved beyond 
question that this conidial form really belonged to it. 
Brefeld 3 gives a long and very interesting account of the 
different forms of chlamydospore already observed in a few genera 
of Basidiomycetes, and in conclusion his observations may be shortly 
summarised as follows. The very simplest forms are the so-called 
“ oidia-chains (Oidienketten); these appear to be produced by the 
simple division of the hyphse into long chains of cells, and a whole 
mycelium may sometimes break up in this way. The single limb on 
germination again produces an Oidia-chain and so on for generation 
after generation. Examples of this kind of formation have been 
recorded for various genera such as Phlebia, Irpex, Pholiota, Hypho- 
loma, Collybia, etc. Brefeld goes on to say that though these 
“ oidia-chains ” are the simplest known form of chlamydospores, 
they are not the only ones. Various oidia-forms, slightly more 
differentiated than those just described, have been observed, and at 
length a higher form is reached, to which alone, strictly speaking, 
the term chlamydospore is applicable. So far the latter have been 
discovered only in the genus Nyctalis amongst the Agaricini, and in 
Fistulina and Oligoporus amongst the Polyporei. 
In the first genus, the formation of true chlamydospores 
appears to be always preceded by the formation of “ oidia-chains,” 
in the other two genera the latter are wanting. 
It seems that very often the chlamydospores arise in special 
positions in relation to the true fructification or hymenial layer 
(cf. Brefeld, Plate VI., Fig. 4), actually appearing in company with 
the basidiospores. At other times, however, they are borne in great 
numbers by the hyphae of the ordinary mycelium. Brefeld further 
observes that short branches may be sent up into the air on which 
the spores are borne not interstitially, but terminally, which is 
1 Zersetzungserscheinungen des Holzes, p. 112. 
2 Bull, de la Societ6 Botanique de France. Tome XXXI., p. 296. 
3 Untersuchungen aus dem Gesammtgebiete der Mykologie. 
Heft VIII., p. 206, etc. 
