368 THE JOURNAL OF BOTANY 



has often been placed under Puccinia Porri (Sow.), or under 

 P. mixta Fckl. as forma siinpUeior Korn., but in Sydow's Mono- 

 gra])}iia (ii. 263) it is treated separately as U. amhigiius. The main 

 distinction, of course, lies in the one-celled teleutospores, but it 

 also presents larger sori than the Puccinia, which remain always 

 covered by the leaden-grey epidermis. In the specimens before 

 me these are more conspicuous on the stems, on which they 

 form lanceolate patches as much as 12 mm. long. 



The difficulty lies in the fact that P. Porri produces an 

 abundance of mesospores (one-celled teleutospores), which have 

 the same appearance as the teleutospores of the Uromyces ; they 

 are, in fact, almost indistinguishable except by their much greater 

 variability. But the Puccinia also produces its proper two-celled 

 teleutospores, which can be found intermixed with the meso- 

 spores ; while one may search in vain for such in the Uromyces, 

 as I have done again and again. 



While, therefore, it cannot be stated with certainty, in the 

 total absence of culture-experiments, that the two species are 

 really distinct, it seems better for the present to keep them so, 

 especially as P. Porri has secidia and the Uromyces has not, and 

 there are other small differences as well. The Uromyces is stated 

 to be confined to Allium rotundum, A. Schcenoprasum, A. Scorodo- 

 prasum, A. spkarocephalum, while the Puccinia is found on those 

 and many other species of the genus. 



Uromyces Lilii (Link) Fckl. Mr. C. W. Lowe gave me good 

 specimens of this species during the past summer froin his 

 garden at Edgbaston. Here it occurred on the leaves of Lilium 

 candidum ; the host-plant has been in the garden for several 

 years, but the parasite had not been noticed before. The spermo- 

 gones and secidia appeared together about May, on pale oblong 

 or lanceolate spots, about half an inch long. These were followed 

 in June by the sori of teleutospores ; by this time the spots were 

 larger, and on them the large black sori made a conspicuous 

 object. The aecidial cups remain for a long time closed, and never 

 become cup-shaped because the margin is not revolute. The 

 teleutospores are rather globose, with a prominent hyaline papilla, 

 and are striated with indistinct, often interrupted, lines or with 

 warts arranged in lines. It is difficult to account for the occur- 

 rence of this species, unless the spores were wind-borne, since, so 

 far as is known, no new introductions have been made into the 

 garden by which it could be conveyed. 



DoTHiDELLA Betul^-nan^ (Karst). In a paper on " The 

 Ecology of the Upper Driva Valley in the Dovrefjeid," by 

 W. West & G. S. West, in the Neio Phytologist, vol. ix. (1910), 

 p. 371, a figure is given of " leaves of Betula nana attacked by a 

 leaf-blotch fungus [Bhytisma sp.)." At the time when this was 

 published, the preserved specimens brought from Norway had 

 been mislaid and could not be found. Since then they have been 

 discovered, and by the kindness of Professor West I have ex- 

 amined them and find that the parasite is the imperfect stage of 



