Some Remarks on Mr. Takahashi's Paper on 



the Identity of Ustilago virens Cooke 



and Ustilaginoidea Oryzse Brefeld. 



By 

 J. Omori. 



In the last number of this Magazine Mr. Takahashi of Sapporo 

 described the morphology of Ustliago virens together with a new- 

 species of Tilletia parasitic on the rice-plant, and expressed his views 

 on the identity of the former with Ustilaginoidea Oryzce recently 

 described by Brefeld. As regards his new species we have nothing to 

 say, but as to the opinion that Ustilago virens is identical with 

 Ustilaginoidea Oryzce I think it requires some further proof. 



First of all, let us examine this question. Although Mr. Takahashi 

 describes the resemblance of morphological characters of these two 

 fungi, they are proved to be quite different when we examine the mode 

 of their germination. Thus the germinating spores of Ustilago virens 

 produce in a culture solution sporidia which multiply by budding like 

 yeast without intervension of promycelium (1) as it is the case with 

 Ustilago olivacea , (2) while the germinating spores of Ustilaginoidea 

 Oryzce produce, according to Brefeld, hyptise which bear conidia. (3) 

 Thus in spite of the close resemblance of the other morphological 

 characters the difference regarding the mode of germination is so great 

 that we need no further discussion about this question. So the fungus 

 hitherto referred to Ustilago virens Cooke by Messrs. Tanaka, Hori, 

 and Takahashi proves not to belong to the Ascomycetes like Usti- 

 laginoidea, but to be a distinct species belonging to the Ustilaginece. 



As regards the structure of the sporiferous body Mr. Takahashi 

 described at full length the three spore-producing outer layers and 

 the central medulla composed of a sclerotioid mass of hyphal weft; 



C1 ' The details of this development will be soon published in the "Bulletin" of the 

 College, of Agriculture, Imperial University. 

 (2 ' Brefeld, Bot. Unteisgn. iib. Hefenpilze, Heft V, Taf. X, Fig. 12. 

 ^ Brefeld, Bot, Cent. Bd. LXY, No. 4, 1896. 



