He t crop ucc in ia . 



I 



Teleiitospores — Sori blackish, large (2-4 mm. long by '5 mm. high), 

 compact, pulvinate, elongate, with numerous smaller ones scat- 

 tered between. Spores oval, fusiform, or subcylindrical, 

 brovvn, granular, markedly constricted. Upper cell slightly 

 . thickened above, rounded above and below, lower cell similar 

 in form, but more attenuated below, 50-60 X 20-23/u,. 

 Pedicels brown, stout, persistent, 75-100 x 6-8/>t. 



Sytionyms. 



Vadium rinnicis, Grev., in part. 

 yEcidhim rubdlum, Pers., in part. 

 ruccinia phragmitis (Schum.), in part. 



^cidiospores on Rumex acetosa. 



Uredospores and teleutospores on Phragmites couiiiiimis. 

 ^cidiospores, May and June ; uredospores, July and August ; 

 teleutospores, August to June. 



Biology. — While studying the life-history of Puccinia phragmitis 

 and magnusiaiia^ I became convinced that a third species occurred 

 upon the common reed, which had its a^cidiospores on Rumex acetosa. 

 Professor Trail was fortunate enough to find near Aberdeen a Puccinia 

 on reed, and in close proximity to it the yEcidium on R. acetosa., and, 

 although other Rumices were growing equally near, none of them had 

 the Eecidiospores on them. From specimens he was kind enough to 

 send me in July, 1888, the above descriptions have been drawn up. 

 The teleutospores, while closely resembling those of P. phragmitis, 

 differ in having a granular spore-membrane, and in being borne on 

 stouter pedicels. The last year's teleutospores collected by him in 

 June and July were found to germinate freely, and on July 29 were 

 applied to R. acetosa and crispus (Exp. 950, 951), and on August i to 

 R. acetosa, crispus, obtusifolia, and Rheum officinale. The a^cidio- 

 spores were produced in due course upon R. acetosa, but not upon the 

 other plants. 



Puccinia magnusiana. Korn. 



x^cidiospores — Pseudoperidia in small circular groups on the 

 leaves, mostly hypophyllous, with everted, toothed, whitish 

 edges. Spores subglobose, 15-25/x in diameter. 



Uredospores — Sori orange-brown, small, elliptical or linear. Spores 

 globose, ovate or elliptical, finely echinulate, orange-yellow, 



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