246* X39 Mycologia 



mm. wide by 0.5-1.5 mm. long, sometimes confluent, long covered 

 by the epidermis, grayish-black; teliospores clavate or oblong- 

 clavate, 15-21 by 45-5 5/a, obtuse or truncate above, narrowed be- 

 low; wall chestnut-brown, paler beneath, thin, about i/x, thicker 

 at apex, 3-5/x, smooth ; pedicel short, slightly colored. 



On Koeleria cristata (L.) Pers., Ouray, Colo., Aug. 23, 1907, 

 E. Bethel (type) ; Boulder, July 31, 1905, Plainview, Aug. 5, 

 1905, and April 25, 1908, Marshall, June 24, 1905, Golden, July 

 27, 1908, all in Colo., E. Bethel. 



6. Puccinia on Bromus. A subepidermal rust on various spe- 

 cies of Bromus is common in the western mountains. Collections 

 made by Prof. E. W. D. Holway, Sept. 4 and 7, 1907, on B. 

 Pumpellianus Scribn., at Banff, Alb., were found close to Thalic- 

 trum bearing aecia, and believed by him to be connected, but the 

 teliospores could not be brought to germination. A collection on 

 B. Porteri (Coult.) Nash, made by Mr. F. D. Kern, Sept. 2, 1908, 

 at Ouray, Colo., with much more definite and certain field clues, 

 being intermixed with Thalictrum sparsiflorum bearing aecia, 

 was found more tractable and was sown April 30, on Thalictrum 

 dioicum, giving rise to pycnia May 9, and aecia May 30, both in 

 abundance. 



It has long been recognized that the aecia on Thalictrum in 

 America belong to a number of species. No cultures, however, 

 have been made heretofore, and only the form associated with 

 Tranzschelia punctata {Puccinia Pruni-spinosae) , common in the 

 eastern part of the country, has been definitely placed. In Europe 

 cultures have shown aecial forms on Thalictrum to belong to 

 telia on Agrostis, Poa, Triticum, Elymus and Polygonum. 

 Whether any of these occur in America, remains to be deter- 

 mined, although the last two are to be expected. The species in 

 hand appears to be unrecorded, and a description is therefore ap- 

 pended. It is closely related, both morphologically and in its 

 hosts, with P. tomipara Trel., which ranges throughout the central 

 and eastern states with its aecia on Clematis and telia on Bromus. 

 The question of their exact relationship must be left to future 

 investigation. 



Puccinia alternans sp. nov. 



O. Pycnia epiphyllous, crowded in groups 0.5-4 mm. across, 

 not conspicuous, subepidermal, in vertical section globoid, 60-96/x 

 in diameter, 50-80^ high. 



