2oS . :.- - ■ ■■ s. iTO. .■ ■ ; : 



TuANZCIlELfi) asserts that Fuccinia on Poa iiauora/is has no connection 

 whatever with the ^-Ecidium on Petasitci officinalis. 



In our Flora, Titssilago Farfara is not present. On Pctasitcs jaf-oniciis, 

 however, the aecidial stage is very common!)' found ; and in the vicinity of 

 such an infected plant, there occur frequently different species of Poa badly 

 attacked by Pjtcciiiin Poariiu:. It is not unreasonable, therefore, to believe 

 in this case in the possibility of the relationship existing between two forms 

 of rust fungi. In our country, no infection experiments have yet been made 

 to prove their genetic connection. 



The JEcidium on Pctasiics in our country agree in general characters to 

 that OH Tiissilago in Europe ; and in the present paper, I have considered it 

 provisionally as a stage o{ Pucciiiia Poaruiii. 



I got, from Mr. T. MiYAKE, a Saghalien specimen of /Ecidium on 

 Pctasites japonictis. It was found mixed ^vith the sori of Pucciiiia cxpausa 

 Link. But as Pucciiiia cxpausa belongs to Hemipuccinia, having no aecidial 

 stage, and moreover as the Saghalien /Ecidium coincides exactly with that 

 of Hokkaido in their morphological character, it may well be regarded as a 

 stage ol Pucciiiia Poaruin and not o^ Pucciiiia cxpausa. 



The uredoson oi Pucciiiia Poai'inn are distinguished from those of other 

 related species by the presence of characteristic capitate paraphyses. 



As it has been remarked by Lagerheim and Carleton, the uredo- 

 sporesofthis species hibernate also in our country. In Sapporo, on Poa 

 annua, onl)' the uredospores seem to be formed and the tcleutospores so far 

 have never been observed. The uredospores in this case are formed 

 throughout the year from early spring to late autumn and even under the 

 snow in winter. 



The teleutospore of our plant is slightlj' larger than that of the European 

 form ; but in other points they agree exactly. 



In 1903, DiETEL (7) regarded the Uredo on Poa pratensis, collected by 

 Mr. Nampu at Nishigahara, as a different species from that of the presei>t 

 plant. I have no specimen in my hand which correspond to DieTEL's 

 description. 



I have collected in our Botanical Garden a species of Puccinia, much 

 recsmbling the present species, on Dcscliavipsia cacspitosa, introduced by 



