Hemmi: On a Disease of some Leguminous Plants caused by Ceratophorum setosuin Ktrchner i [o 



leaflets. The old spots are brown or dark brown and sometimes chestnut-brown 

 on the upper surface of the leaves, and very much lighter on the under side. Al- 

 though the spots are not bordered with a special color, they are on the upper sur- 

 face sharply separated from the green healthy part of the leaf, while on the under 

 surface their margin is not distinct. The large circular spots show sometimes 

 many concentric rings of the dark colored lines on the upper surface. The diseased 

 leaflets die early and soon dry up in the summer or in the early autumn. 



4. Morphology of the Causal Fungus 



The mycelium of the fungus is composed of slender, hyaline, septate hyphae 

 which grow mostly between the cells of the host. Some of the hyphae, appearing 

 on the upper side of the leaves, creep on the surface of the diseased spots. A 

 section through the diseased spot shows the hyphae to be ramifying in the tissue 

 of the leaf, and the chloroplastids destroyed. The mycelium within the tissue or 

 on the surfcice varies greatly in diameter. Many of the lateral branches are very 

 slender, while the older hyphae may become greatly swollen. The hyphae found 

 in the tissue are hyaline, many septated, 2-10 // in diameter. The creeping hyphae 

 on the surface are generally poorly developed and are also hyaline. In cultures, 

 the mycelium is at first colorless, then gradually turning into light brown or 

 brownish gray in color when seen under a microscope ; and it develops largely in 

 substratum, where it forms many intercalary knots of chlamydospores presenting 

 an appearance of black dots in the media to the naked eye. 



Conidiophores are short and straight and are formed here and there on the 

 creeping hyphae on the surface of the leaf. They are generally simple, but rarely 

 branched. They are not easily distinguished from the normal hyphae in their 

 appearance. The spores are at first produced as the hyaline, club-shaped swell- 

 ings at the tips of the conidiophores. Afterward a septum is formed at the base 

 of each swelling. In the course of development, they produce 4 or 5 rarely 6 

 transverse septa, and 3 or 4 sometimes more setae from the uppermost cell. At 

 the same time, the spores turn gradually into brown or dark brown color. The 

 matured spores are very much like to those of Pestalorjzia in their morphological 

 characters. They are cylindro-fusiform in shape and mostly more or less curved. 

 The middle one or two cells of the spore are darkest, while the ba.sal and terminal 

 end cells are generally very light in color or sometimes nearly hyaline. Accord- 



