LYMAN: STUDIES OF HYMENOMYCETES. 
139 
of Russula and obtained normal fructifications of Nyctalis. Brefeld 
(’89) repeated Krombholz’s experiment, and, in addition, found that 
the mycelia from germinating basidiospores produced the character¬ 
istic chlamydospores and also oidia in abundance. Finally, Costantin 
(’91) germinated the chlamydospores in a variety of culture media,, 
and traced their development to the formation of basidia. 
Conidia have been reported in several species of this family as 
described below, but they seem to be of small importance in the life 
histories of the fungi concerned, and the more interesting forms need 
to be investigated further that their basidiomycetous nature may be 
fully demonstrated. 
Conidia were observed by Patouillard (’80, ’81, ’87a) in specimens 
of Pleurotus ostreatus grown under conditions unfavorable to perfect 
development. The stalks and caps become villous with short septate 
simple or branched hairs, some of which, particularly those about the 
margin of the pileus, produce small colorless conidia, which are borne 
singly on each cell on terminal or lateral sterigmata. Brefeld (’89) 
cultivated Pleurotus ostreatus and found oidia, but makes no mention 
of conidia. Matruchot (’97), however, corroborates Patouillard’s 
observations, finding such conidia on the margin of the pileus and in 
the hymenium. The latter region also contains numerous bodies 
which he calls cystidia, each bearing one, two, or three sterigmata 
with terminal swellings. Moreover, in eight-days-old cultures the 
mycelia produce cells (called pseudoconidia) similar to the conidia 
of the pileus. Matruchot found gradations between these three 
different spore forms, and regards all the conidiophores as modified 
basidia. So far as he could tell, the various spores are incapable of 
germination. 
According to Heckel (’80) the glands of Pleurotus glandulosus are 
composed of basidia transformed into long hairs that bear spores 
laterally in varying number. 
In Pleurotus craterellus the stalk is represented by a small tubercle 
covered by hairs whose swollen ends produce one to several oval 
conidia, borne side by side (Patouillard, ’87a). 
Eichelbaum (’86) says that a conidial modification of the basidium 
may be induced in any agaric by keeping it for some time in a damp 
chamber. The basidia lengthen into slender threads, each bearing 
at its extremity a large round cell which occasionally shows yeast-like 
budding in situ. All gradations between these slender conidiophores 
