35 2 
Marshall Ward . — On a lily -disease. 
Series III. 
A fine mycelium, about the same size as the last, was re- 
moved on August 7th from its flask (it had been growing since 
July 17th on Pasteur’s solution with a little peptone), allowed 
to drain, and pounded as before in a mortar, but with the 
addition of a few cubic centimetres of distilled water, instead 
of its own juice. The pounded mass was allowed to stand 
for an hour at the ordinary temperature, and then three sets 
of culture-chambers were arranged as in Series I. 
In the first set of three chambers, the hanging drop was of 
the raw unfiltered extract. 
In the second set, also of three chambers, the drop was of 
the unboiled but filtered liquor. 
In the third set, also of three, the drop was of the boiled 
and filtered extract. 
In each drop was placed a thin section of the peduncle of 
the white lily, and the preparations were examined from hour 
to hour. 
In sets one and two the results were observable in the course 
of the first hour, and after six hours the cellulose-walls were 
all striated and swollen as in Fig. 60. It should be remarked 
that the swelling action was more vigorous in the unfiltered 
liquor than in the filtered one. 
In the third set, where the drop consisted of the filtered 
liquor boiled for five minutes, no swelling of the cell-walls was 
observable in six hours. 
I now felt satisfied that the action was really due to a 
soluble ferment, of the nature of a zymase, excreted by the 
fungus in question ; but the question still remained as to the 
possibility of really isolating the ferment, for it had to be 
admitted that such an extract as the above must contain a 
mixture of substances. 
Adopting the well-known method of precipitation by alcohol, 
the following experiments were carried out. 
