Hemmi : A New Brown-Spot Disease of the Leaf of Glycine hispida Maxim. 



13 



was not a little, for every fields were more or less affected by it. 



Later in the same year, during my botanical excursions in the Province Iburi 

 in August and in the Provinces Kitami, Tokachi and Ishikari in September, I 

 observed and collected the diseased leaves at several places. The fungus in ques- 

 tion was first collected in 191 3 by Prof. K. Miyabe in the Province Kitami and I 

 could examine it through his kindness. These facts show that the disease is very 

 common and very widely distributed throughout Hokkaido. In August of this 

 year, Prof. S. It5 found the same fungus in the Province Echigo in Honshu. 

 Judging from the extent to wliich the fungus has spread in the field, we may also 

 safely infer, that the disease had existed there for many years without drawing 

 our attention, and in 1914 it happened to take somewhat the character of an 

 epidemic. 



As the disease was common in the vicinity of Sapporo, I had many oppor- 

 tunities of studying carefully its s}'mptoms as well as the nature of its causal fun- 

 gus ; and in consequence, I have been able to recognize that the fungus in ques- 

 tion is a new species which has passed undescribed up to the present time. 



Symptoms of the Disease. 



The disease appears first upon both sides of the lower leaves of young plants 

 as brown or light reddish brown spots in the early summer. Those spots are 

 slightly raised and angular and distinct in outline, being limited by veinlets, and 

 are scattered irregularly over the surface. The color of the spots gradually turns 

 into dark brown and finally into blackish-brown. They are comparatively large 

 and are most commonly 2-3 mm. in diameter, but not seldom they exceed 5 mm. 

 The margin of the spot is not especially bordered with a deeper color as in the 

 other type of Septoriose. The spot is more or less hypertrophied. The old spots 

 frequently turn into grey color from the central region, the close examination of 

 which, especially with a magnifying hand lens, reveals exceedingly small dark- 

 colored pycnidia scattered throughout. The spots become confluent often forming 

 large irregular brown or dark-brown patches, and the diseased leaves also turn 

 gradually into yellow or brown color from the margin, then become dry and fall off. 



The disease then works toward the top of the plant, often causing the loss of 

 so many leaves as to result in complete ruin of the crop. The disease spreads most 

 rapidly in a damp warm weather or in places which are incompletely drained. But 

 in the mid summer or in a dry region, the disease does not attack the upper leaves. 



