896 
Journal of A gricultural Research voi. xxiv, No. n 
This treatment caused some discoloration of the fruits but no softening. 
It had no visible effect on susceptibility to infection by this fungus, for 
fruits treated with weak solutions of bichlorid of mercury or formalde¬ 
hyde as well as fruits not treated were quite as readily infected. 
Controls were liberally used in all the experiments. Both the controls 
and the inoculated fruits were usually kept in closed glass chambers to 
prevent contamination from the air, but inoculated fruits kept in open 
dishes were quite as readily infected. 
The decomposition of the cell constituents was observed on roots of 
carrots and on green tomato fruits. Sections of carrot roots, chiefly from 
the heart, and of green tomato fruits, 250 and 500 jx thick, respectively, 
and free-hand sections of varying thickness were used as fresh material. 
Pieces of green tomato fruits from spots 2 days old were treated with 
Flemming's medium killing and fixing solution, embedded in paraffin, 
and sectioned and stained for the study of fixed material. 
The cultures were made as described by Brown {sY on thin layers of 
media (carrot decoction, and beef bouillon + 2^ per cent glucose) in 
small flasks or Petri dishes, inoculated with an optimal quantity of spores, 
and kept at a temperature of 22° to 26° C. 
The action of the enzyms on the host cells was determined by means 
of the live organism, the ground-dried organism, the extract from the 
ground-dried organism, the filtrate from cultures, and the alcoholic 
precipitate from the filtrate. 
The organism was separated from the culture medium by passing the 
liquid through a double layer of Whatman’s No. 50 filter paper. A few 
small cells passed through the filter but showed no signs of germination 
during the experiment. 
The enzymic material was precipitated by adding 4 volumes of 95 per 
cent alcohol to each volume of the filtrate. The liquid was then filtered 
and the precipitate washed in 95 per cent alcohol, dried in a warm air 
current, dissolved in a very small quantity of distilled water, and used 
immediately. 
The ground-dried organism was used in aqueous suspension. The 
extract of the same material was prepared by soaking the powdered 
fungus in water for 24 hours. 
The decomposition experiments were run for 24 hours at temperatures 
ranging from 24° to 45° C. Growth of microorganisms was prevented by 
adding chloroform or toluene to the liquid in the proportion of 10 to 25 
per cent, but duplicate experiments in which no antiseptic was used were 
also made. Chloroform and toluene inhibited growth without apparently 
hindering the action of the enzym. 
RlSSUIyTS OR INOCULATION 
The results obtained with both pricked and unpricked fruits are sum¬ 
marized in Table I. 
Of the 277 pricked fruits inoculated, 208, or 75 per cent, became 
infected. The ripe fruits seemed to be somewhat more susceptible than 
the green fruits, but both were easily infected through punctures. The 
infections of unpricked fruits took place only through the stem scar. 
This was frequently observed in preliminary experiments not recorded. 
Moreover, it appears to be the cause of the position of the rotted areas 
of this type on most shipped fruits. 
* Reference is made by number (italic) to “Literature cited,” p. 905. 
