335 
Marshall Ward ’ — On a lily-disease. 
in small drops of thin solutions, or in drops of partially ex- 
hausted Pasteur’s solution, the mycelium produced fewer and 
poorer organs of attachment, and soon proceeded to the 
development of the conidiophores, and then ceased to grow 
further unless new food-materials were added ; in denser and 
richer solutions, or in larger drops, on the contrary, the 
mycelium often grew from 10-12 days without passing to the 
development of the conidiophores. In the former cases it 
was possible to trace the whole development of the conidio- 
phores and conidia without difficulty, because, there being few 
obscuring hyphae, etc., the same specimen could be kept under 
constant supervision. 
In F'ig. 32 I have drawn a mycelium cultivated from a 
single spore in a drop of partially exhausted Pasteur’s solu- 
tion : the culture was five days old. As seen, the mycelium 
is not very large or complex, and even the original spore can 
be recognised at S. On the hyphae at various places are large 
numbers of bubbles of gas, A A, a common occurrence when 
conidiophores are about to be produced : such bubbles are 
also found on the conidiophores themselves (Fig. 35) so long 
as they are submerged, but as they usually project from the 
surface of the drop of culture-liquid into the damp air of the 
chamber, the gas-bubbles are often not seen on them. 
At C C in Fig. 32 are several conidiophores, bearing the 
well-known heads of Botrytis - spores which look like bunches 
of grapes. The conidiophores are produced in centrifugal 
order, by the outgrowth of thick blunt hyphae (Fig. 39) from 
certain not well defined branches of the mycelium. 
The development is best illustrated by describing a concrete 
case— Fig. 34. The outgrowing colourless hypha is very full 
of dense protoplasm, often delicately vacuolated, and its rather 
blunt end soon begins to swell into a club-like shape : in this 
condition it looks very like the young sporophore of Mucor , only 
it soon becomes septate-at short intervals. In the case figured 
this stage was reached by 4.45 p.m., and beneath the club-like 
end of the branch two little protuberances were appearing 
(Fig. 34, 1). At 5 p.m. the protuberances had grown out into 
