I 2 I 
Bulgaria polymorpha , /%//. 
My chief object in examining the biology of this Fungus 
was to observe the effects of its action on wood, but as 
the cultures afforded a good opportunity, the course of 
development was also traced in some detail. 
The ripe ascophores used for this investigation were 
gathered on December 5, 1898, and a further supply was 
obtained in December, 1899. They are also said to occur 
during the summer months, but so far I have not found them 
except in the winter. 
An examination of longitudinal sections of the ascophore 
showed that it was traversed by dark brown veins, which 
anastomosed immediately below the hymenium (PL VII, 
Fig. 1). Under the microscope the veins were found to 
be channels bordered by hyphae with thin dark brown walls, 
while the mass of the ascophore consisted of hyphae with 
strongly swollen walls. To such an extent was this swelling 
carried that the walls formed a solid gelatinous mass. 
The hymenium consisted of delicate whip-like paraphyses 
and asci characterized by containing two apparently different 
forms of ascospores — a comparatively rare occurrence in the 
Ascomycetes, for all eight spores are usually similar to one 
another. In this case four had thick dark -brown walls and 
a deep longitudinal infolding on one side, while the remaining 
four were colourless and thin-walled. The position of the 
smaller spores was variable, at times they were crushed into 
the apex of the ascus or scattered irregularly among the 
large brown spores. Occasionally, but very rarely, all the 
spores had thick brown walls. The apex of the ascus was 
coloured blue by an iodine solution. 
On placing the ascospores in beer-wort gelatine they ger- 
minated within twenty-four hours (temp. 14 0 C.), and rapidly 
gave rise to a dense mycelium. Both the coloured and 
colourless spores behaved in this way, and beyond the fact 
that the colourless spores germinated first I could find no 
difference between them. In about four days the walls of 
the mycelium began to swell, the swelling starting from the 
spore and gradually working its way along to the younger 
