630 Howard.—On Trichosphaeria Sacchari , AT as see. 
all cases the wounds were covered with sterilized vaseline 
to prevent the entry of other spores. In eight days the tissues 
of the cane for some distance round the point of infection 
were much discoloured, and microscopic examination showed 
that the cells were filled with mycelium which passed from 
cell to cell by means of pits in the walls after the manner 
described by Massee. Cultures made of portions of this 
discoloured tissue showed the copious development of micro- 
and macroconidia in two days. The control experiments 
showed no infection. 
Microconidial stage. 
It now became necessary to obtain a single spore-culture 
of this phase of the Fungus and follow out the development 
as in the case of the macroconidia above. 
A hanging-drop culture was obtained containing a single 
microconidium. The spore germinated six hours after sowing 
and sent out a colourless septate hypha which soon branched. 
The mycelium quickly extended right through the drop, 
and its subsequent development was similar in all respects 
to that described above in the case of the macroconidia. 
Aerial microconidiophores were formed as before which ejected 
chains of microconidia, while the submerged hyphae formed 
chains of macroconidia inside the drop. 
The number of microconidia formed by one conidiophore 
is frequently very large, as many as ninety being observed. 
The development of the micro- and macroconidia is there¬ 
fore practically identical; had the drops not been labelled 
it would have been impossible to have distinguished between 
them. 
In several cases the microconidia in this and other drops 
were noted, when a few days old, to germinate in the drop 
in a curious manner. A narrow hypha was produced 180 /x or 
more in length, into which the brown contents of the micro¬ 
conidium passed, leaving the conidium empty and colourless. 
