90 
Biologie — Physiologie 
abgestorben ist. Auf beiden Seiten dieses Pfades herrscht üppiger 
Pflanzenwuchs und es finden sich die über 20 cm breiten Fruchtkörper 
einer Agaricus- Art, wahrscheinlich Agaricus maximus. Wenn sich der 
Pilz ausbreitet so wächst zunächst das Gras unter seinem Einfluß besser, 
um erst später abzusterben, nach Ansicht des Verf. deshalb, weil durch 
das Mycelgeflecht kein Wasser mehr zu den Pflanzenwurzeln gelangen 
kann. Über die erste Entstehung des Hexenringes konnte Verf. nichts 
ermitteln. Versuche, denselben vermittelst herausgegrabener Bodenstücke 
zu verpflanzen, blieben ohne Erfolg. Kurt Trottner. 
COTTON, A. D., On the production of imperfectly developed 
spores in the Agaricaceae (Trans. Brit. Mycol. Soc. 1914, 4, 
298—300). 
Düring an examination of Stropharia semiglobata the question was 
raised as to whether the first shed spores from a given pileus differed 
at all from those whicli were liberated later. To determine this a suc- 
cession of spore-casts was prepared. Vigorous young sporophores were 
used and the pilei set on white paper in the ordinary way, covered witli 
small glasses, and shifted every hour to a fresh position. “Microscopic 
examination of the spores gave a rather startling result. Wliilst those of 
the first day measured 18—20x9—10 g and were a deep purple black, 
those deposited on the morning of the third day were not more than two- 
tliirds of the original size and mucli paler in colour. The intervening 
spore-casts showed a gradual diminution in size, though this was not noti- 
ceable during the first few hours.” The experiment was repeated witli 
other species but as the spores were not of such large size the results 
were not so striking. By studying the fungi under natural conditions it was found 
that old specimens showed spores that were of normal size, and in no 
case was there a crop of small spores. “The explanation lies doubtless in 
in the fact, that in the first case the pilei were separated from the stalk, 
and the experiments performed in a dry warm atmosphere; under these 
conditions spores continue to develop for two or three days, but are poorly 
nourished and fall off without reaching the normal size.” 
J. Ramsbottom (London). 
BROOKS, F. T., Observations on pure cultures of some Asco- 
mycetes and Basidiomycetes (Trans. Brit. Mycol. Soc. 1914, 4. 
239—248). 
The author first considers the previous work on lignicolous fungi 
grown in pure culture and then describes bis own observations on such 
species grown on blocks of wood resting upon plugs of cotton wool satu- 
rated with water. Blocks of Fraxinus and Quercus on which Chloro- 
splenium aeruginosum was grown were green throughout. “Sections sliew 
that the green hyphae of the fungus have penetrated to the centre of the 
block and are especially abundant in the vessels. The walls of some of 
the elements of the wood assume a greenish colour but the chief factor 
in the colouring of the wood is the accumulation of lumps of a green 
amorphous substance in the different elements especially in the cells of 
the medullary rays.” Conidia similar to those described by Brefeld 
have been produced in the cultures, but no formation of spermagonia as 
described by Tulasne or of ascocarps has yet taken place. In the case 
