225 
OBSERVATIONS ON BREFELDIA MAXIMA, Rost. 
A. R. SANDERSON. 
WHILE searching for Mycetozoa in the Clapham district (Trow 
Ghyll) in November, 1913, I had the good fortune to see a 
large plasmodium of Brefeldia maxima, which had just emerged 
from an old ash stump preparatory to fruiting. The large 
plasmodium—in many places two inches in thickness, was 
spreading over the vegetation (chiefly old stems of nettles) in 
the immediate vicinity of the stump, but by far the greater 
mass, covering in all about four square feet, had moved much 
further away and was spreading over the vertical faces of the 
limestone rocks, where fruiting was eventually completed in 
the form of large dark brown ethalia, many of these masses 
being several square inches in extent. In October, I914, a 
similar large plasmodium of the same species was noticed 
issuing from another decayed ash stump, about two hundred 
yards higher up the valley—the same stump also yielded large 
colonies of Lycogula epidendrum, Physarum nutans, Trichia 
scabra, Tricha varia, Hemitrichia. clavata and Arcyna 
denudata. J collected several large masses of the plasmodium 
of Brefeldia maxima and kept them under observation until 
spore formation was completed. One mass in particular about 
8 ins. long, 3 ins. wide and 2in. thick was carefullly watched, 
and in a few hours’ time, the upper surface, which was still 
creamy white, showed evidences of demarcation into definite 
small rounded areas, marking the limits of the individual 
sporangia. 
At quite an early stage, these signs became much more 
pronounced at, and around definite centres in the plasmodium 
where the mass became rather more heaped up. The heaping 
up at and round these points became more marked as develop- 
ment proceeded, while the limits of the individual sporangia 
became more strongly marked than in the surrounding parts 
of the plasmodium further distant from the centres. As 
development continued, it became more and more evident 
that fruiting had commenced at certain points approximately 
equidistant from each other and from these points was spreading 
gradually outwards. At a still later stage, further evidence 
of this was shown by the coloration, for at the centres the 
creamy white appearance had given place to a very pale brown 
which now more rapidly darkened, and passing outward 
from the centres, the colour gradually changed in shades of 
brown becoming paler to the extremities of well marked zones. 
Finally the colour at the centre became very dark brown and 
this change gradually spread outward as spore formation was 
completed: in the zone. Further, at all the centres, fruit 

1916 July 1. 
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