146 LEVINE: CYTOLOGY oF HYMENOMYCETES 
Older mycelia of Pholiota praecox were obtained by sowing 
the spores in Petri dishes partly filled with bean, cherry, or malt 
agar. These were kept in the dark. After three days sufficient 
growth results to make the fungus visible to the naked eye. The 
cultures were then transferred to test tubes, from which subsequent 
cultures were made. 
Mycelia of Polyporus adustus, P. betulinus, P. destructor, 
P. versicolor, Collybia velutipes, and Coniophora cerebella were 
obtained in pure culture from the Association Internationale des 
Botanistes. These were propagated by transferring small pieces 
(2-5 mm. sq.) of the mycelium to Petri dishes with malt-beef, 
cherry, and bean agars. To secure perfect penetration of the 
fixative in the case of mycelia, the method described by Miss 
Nichols (1904) was used. 
Most of my material was collected in the vicinity of New 
York City. A number of Boleti were also sent to me from Woods 
Hole. In all, the carpophores of twenty-four species of Boleti and 
three species of Polypores were studied. Of these Boletus granu- 
latus, B. castaneus, B. albellus, B. versipellis, B. vermiculosus, 
B. glabellus, B. chrysenteron, B. indecisus, and B. pallidus were 
the more favorable for cytological work on the mature carpophore. 
I have not succeeded in germinating the spores of any of the 
Boleti. 
Flemming’s weaker solutions gave the best results, although 
Merkel’s, Juel’s, and Bouin’s gave fair fixations. Flemming’s 
triple stain was used. Heidenhain’s iron haematoxylin also gave 
favorable results. 
To Prof. R. A. Harper, on whose advice this work was under- 
taken, I wish to extend many thanks for his kind suggestions and 
criticisms. 
SPORE GERMINATION AND MYCELIA 
As noted above, the question as to the origin of the binucleated 
cells in the higher Basidiomycetes remains still unsettled. I fin 
that the spores of Pholiota praecox germinate readily and I have 
studied the germ tubes and young mycelium with reference to 
this question. Spores from spore prints, obtained in the manner 
described above, were sown in Van Tieghem’s cells with bean, 
malt-beef, and dung decoctions. 
