48 
mycelium, whereas, on the other hand, a trace of akalinity in the 
nutritive medium retards germination and subsequent growth of 
the mycelium. The conidia also germinate freely on moist stable 
manure, covering the surface within a week with the snow-white tufts 
of the Milowia stage of the fungus, which is followed by the black 
masses of conidia forming the Torula stage. he ascigerous 
condition was not observed. The fact that the fungus can produce 
its two conidial phases as a pure saprophyte is a point of great 
importance from an economic standpoint, and suggests the impor- 
tance of burning all diseased plants, lest they should by any chance 
find their way to the manure heap, from whence the conidia of the 
Torula stage of the fungus would eventually be returned to the 
land in a condition favourable for germination. By such means the 
widespread occurrence of the fungus may probably be explained. 
The chlamydospores resulting from the breaking up of the Torula 
form of fruit do not germinate until after a period of rest, and 
serve to tide the fungus over that period when living host-plants 
are not forthcoming. 
Chlamydospores obtained from aster seedlings that had been 
dried for a year germinated in a very dilute solution of stable 
manure, at the end of four days, and another batch of 
chlamydospores obtained from the same source, germinated on 
sterilised stable manure, and produced the Milowia form within a 
week, followed by the Torula form. Experiments prove that the 
Milowia conidial form constantly reproduces itself ; this takes place 
so long as climatic conditions are favourable for its development, 
and the distribution of the fungus in space depends entirely on 
its Milowia conidial phase. 
A batch of orchids (Cypripedium) attacked by Thielavia, was 
sent to Kew for investigation. ‘The basal portion of each plant was 
soft and decayed, and covered on the surface with a dense, black, 
n 
the laboratory, the white Milowia stage of the fungus developed 
within a few days, and gradually encroached on the still living 
green portion of the leaves. This material, available in quantity 
for the first time, enabled a series of experiments to be made on 
the action of the fungus on germinating seeds and on seedlings. 
