128 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
tions, while the great burden of propagating the species falls upon 
the secondary spores. On the contrary, among the Autobasidio- 
mycetes secondary spores are less commonly known, are less varied 
in character, and where present, frequently appear to be of slight 
value in propagation, so that in this group the basidiospore is the 
main, and in many cases the sole agent of reproduction. 
The literature bearing upon this subject is very unsatisfactory, as 
has already been pointed out. Writers have reported spores, or 
spore-like cells, in addition to the basidiospores, in a large number 
of species; but in many instances these reports are based upon very 
superficial examinations of the fungi concerned, and the alleged spores 
were found merely upon the basidiosporic fructifications. In the 
absence of accurate and sufficient descriptions and illustrations, and 
particularly of culture study of the alleged conidia, such reports are 
open to a two-fold criticism: first, that the conidia may belong to 
foreign fungi growing parasitically upon or together with the Basidio- 
mycetes; and, second, that even though it be admitted in any instance 
that the conidia are produced upon the same mycelium with the Bas- 
idiomycete, it has not been shown that the alleged spore is capable 
of reproducing the fungus, and that it is not a purely vegetative 
structure produced as a result of unnatural or abnormal conditions 
of environment. Such criticisms can only be satisfactorily answered, 
and the correct status of the conidia established, by the germination 
of the latter in cell cultures, with subsequent cultivation to the pro¬ 
duction of normal basidiomycetous fructifications. Careful investi¬ 
gations of this character have been made in comparatively few instances. 
The most extensive culture study of Basidiomycetes is that of 
Brefeld, who has made a notable contribution to our knowledge of 
polymorphism in this class of fungi. In his “Untersuchungen aus 
dem gesammtgebiete der mykologie,” hefte 3 (’ 77 ), 7 (’88), and 8 
(’ 89 ), he records the results of his cultivation of more than two hundred 
species, including about sixty-five genera belonging to various groups 
of Basidiomycetes. Brefeld emphasizes strongly the necessity of 
beginning the culture with the germination of a single spore, but he 
kept his cultures, thus started, on open slides under a bell-jar. Al¬ 
though he exercised great care in removing the slides to the stage of 
the microscope for examination, keeping the atmosphere of the room 
damp and free from air currents, nevertheless it is obvious that there 
is danger of contamination of the unsealed cultures. This danger 
