346 
AMERICAN JOURNAL OF BOTANY 
[Vol. 9, 
very abundant (PI. XVIII, figs, i, 2). This stage was, of course, preceded, 
as in the former cultures on corn meal, by that of the dense white aerial 
mycelium. Next in order of luxuriance was the growth on rye-seed mash 
(PI. XVIII, fig. 3). Here the convolutions of the matted surface were 
much larger, and there was only a hint of a tendency to purple coloration. 
The aerial mycelium progressed much farther down the sides of the flask 
than on corn meal. Sweet potato (PI. XVIII, fig. 9) apparently suffered 
an inhibition of mycelium production of the aerial type, and the surface 
was now well convoluted, of a muddy putty color, on the surface of a 
considerable portion of which was a growth of very short aerial mycelium. 
On white potato (PI. XVIII, fig. 6) there developed a very limited light 
brown, entirely vermiculate growth over the top surface, very small in 
scale compared to previous growths. String bean (PI. XVTII, fig. 8) de- 
veloped the vermiculate type over the entire surface, the convolutions 
small in scale, densely compacted, with a tendency to develop aerial myce- 
lium, on the surface of the medium contiguous to the sides of the fiask. 
Rye screenings (PI. XVIlT, fig. 4) produced a vermicular growth markedly 
raised in the center. Mycelium started on the periphery and grew down 
the side of the flask. The carrot culture (PI. XVIII, fig. 7) developed 
no mycelium at the time indicated, was very finely vermiculate at the 
periphery, and had only partially covered the top surface. The central 
growth was pustular in character. Growth on rye heads after flowering 
(PL XVIII, fig. 5) was chiefly aerial mycelium and appeared to be working 
along the surface rather than permeating the mass. 
From this time on growth was either extremely slow, or had apparently 
ceased. Six months after inoculation growth was characterized as follows: 
On the corn meals the purple, heavily plicated mat developed over 
the entire upper surface and over portions of the sides. The earliest stage 
— the gelatinous — advanced along the sides well towards the bottom. 
Intermediate between these two was an area of aerial mycelium. The 
latter had also developed from the convoluted purple upper surface. There 
was no marked difTerence between growths on yellow or on white meal. 
On rye seed the gelatinous, coarsely plicated pellicle covered all surfaces 
except the base. Aerial mycelium was absent. On rye screenmgs a 
finely vermicular pellicle of light-brown color covered the upper surface 
with no increase of mycelial growth. No further growth was apparent 
on the rye-heads substrate, which was fairly dry. On white potato the 
vermicular growth covered the upper surface and a portion of the sides. 
The carrot flask showed a gelatinous, finely vermicular pellicle covering 
the top and sides of the substrate to its base. A very sparse, short aerial 
mycelium was developing in the center of the top. On the string-bean 
substrate a most compact, finely vermicular growth covered the top and 
three fourths of the sides. Aerial mycelium had started on the sides only. 
The flask of sweet potato had previously been broken. 
