A Dry Rot of the Irish Potato Tuber 
11 
CHROMOGENIC INFLUENCE OF LIGHT UPON FUSARIUM OXYSPORUM 
AND FUSARIUM TUBERIVORUM. 
Solutions of copper sulfate and ammonium hydrate and of 
potassium bichromate were made in the ordinary manner to 
provide screens for the development of the blue and the yellow 
light respectively. Other cultures were placed in the incubator 
and others exposed to sunlight. In general we note that our 
Fnmrium, tuberivorum did not respond quite so readily to the 
light factor as is reported for Fusarium oxysporum by Smith and 
Swingle. (See Table 25.) 
