42 DIPLODIA CORCHORI SYD. 
media but on the cellulose medium and on dead sterile jute stems papillate 
stromata were often produced. 
In artificial inoculations the fungus sets up a very rapid degeneration in 
the tissues of the cortex and phloem (PI. IV, figs. 1,2). In sections of an 
early stage of an infection hyphe can be seen ramifying in all directions in 
the cortex (Pl. IV, fic. 2; Pl. III, fig. 2), and it is evident that a cellulose 
dissolving enzyme is being secreted. The cellulose dissolving power of the 
fungus was tested in cultures upon pure cellulose. A cellulose (parehment) 
diffusion shell was placed in a flask with 50 c¢.c. of the following nutrient 
solution :— 
orm. 
Ammonium phosphate < Ss A 6 
Potassium nitrate of Pe as 6 
Magnesium sulphate - tt i l 
Lactic acid s : < ae 2 
Water er Pe ea :2 1,000 Ge: 
The interior of the diffusion shell was then infected with the mycelium and 
the flask placed in an incubator at 30°C. Within 24 hours hyphe had grown 
through the diffusion membrane into the surrounding liquid. This penetration 
could only be the result of the solution of a part of the diffusion membrane by 
the hyphe. After two months the fungus had formed a dense mycelial growth 
both within aad without the diffusion shell, which had become quite soft 
and rotten. Such cellulose fibres as persist among the fungal hyphee lose the 
characteristic colour reaction with Schultz solution which is given by the 
unaltered cellulose. No sugar could be detected in the liquid in the flask. 
A control flask, which had net been infected with the fungus, remained 
unchanged. 
The fungus was then cultured upon pure cellulose, each culture contaming 
about 0°5 gramme of cellulose and 50 c.c. of the following solution :— 
germ. 
Potassium nitrate es at gt LO 
Monocalcie phosphate wv as zs 5 
Magnesium sulphate oe re a 1 
Water a 4. ah .. 1,000 c.c. 
In this case the only carbon present in the medium was the cellulose. Three 
flasks were infected with the fungus and three were kept as controls. After two 
months, when vigorous growth in the infected flasks had nearly rotted the cellu- 
lose, the flasks were opened and the liquids filtered and made up to a volume of 
100 c.c. From each liquid 25 c¢.c. were taken and then acidified with 11 ¢.c, 
