178 BOTANICAL GAZETTE [MARCH 
contact with the soil underneath a layer of other leaves, the peri- 
thecia were found in early spring to be in approximately the same 
condition. No further development of the fungus occurred on 
the leaves either suspended above the calcium chloride or in the 
normal humidity conditions of the laboratory or of the refrigerator. 
The fungus in the leaves which had been suspended above water 
in a moist chamber, however, did continue its development, and 
by midwinter a few perithecia were found in which the spores 
were apparently practically mature. In most, and finally in all 
cases, however, numerous saprophytes developed in such abundance 
that the Gnomonia fungus was overgrown and destroyed before 
the spores could mature. Other leaves from outdoors were brought 
into the laboratory at various times throughout the winter and 
placed in moist chambers, but the same development of extraneous 
saprophytes soon stopped the observations. In a number of 
instances observed the Gnomonia, apparently in an effort to 
counteract and overcome the encroachments of the more rapidly 
developing saprophytic fungi, began to grow vegetatively, and the 
entire perithecial cavity as well as the ostiolar canal became filled 
with a mass of interlaced and anastomosed hyphae, so compacted 
together that under pressure the perithecial wall would break 
away, but the interior mass would tend to retain its spherical 
shape. This tissue later died and disintegrated, however, leaving 
the empty husk of the perithecium. Among the saprophytes 
which hindered observations a number of forms were invariably 
present. They were, in the main, Cephalothecium roseum, Phy- 
comyces nitens, several species of Penicillium and Aspergillus, an 
Alternaria, a Pleospora, a Crytostyctis, and a Myxomycete. 
Various observations also were made on leaves wintered out- 
side the laboratory. Some leaves were placed on shelves of a 
wire cage, others were placed on the ground and covered with other 
Jeaves and soil, while still others were wrapped in cheesecloth and 
placed on the surface of the ground. In the leaves placed on the 
shelves and on the surface of the ground the fungus was found to 
mature more rapidly than on those leaves covered with other leaves 
and soil, and a very few perithecia were found on such, which 
