JACKSON: UREDINALES OF OREGON 211 



Salix scouleriana Barr. — Cascade Locks, Hood River Co., Aug. 

 II, 1910, 1 178; Myrtle Creek, Douglass Co., June 9, 1914, F. D. 

 Bailey, 334s; Hood River Co., July 23, 1915, 3343, 3366; Ashland, 

 Jackson Co., Sept. 10, 1914, 3340, 3341. 



Salix sp. — Scott's, 7 miles north of Fort Klamath, Klamath Co., 

 Sept. 20, 1913, E. P. Meinecke, Cr D 4, Cr D q; Austin, Grant Co., 

 Aug. 25, 1915, J. R. Weir, 263; Grant's Pass, Josephine Co., Sept. 3, 

 1916, J. R. Weir, 266; White Pine, Baker Co., July 20, 1913, J. R. 

 Weir, 270; Unity, Baker Co., Aug. 1915, J. R. Weir, 278. 



It is impossible to assign with any degree of certainty the collec- 

 tions which should be referred to this combination. Only those col- 

 lections having small, rather thick-walled spores, accompanied by an 

 abundance of capitate, thick-walled paraphyses, are included. It is 

 possible that some of the collections included under M. Bigelowii 

 should be referred here. 



No culture work has been conducted in America. A summary of 

 European work has been made by Klebahn (Die Wirtsw. Rostpilze 

 424. 1904). 



In addition to the above, aecia have been collected in America 

 on Ribes saxosum from Utah, R. vallicola, Colorado, and R. laciistre, 

 British Columbia. 



17. Melampsora Lini (Pers.) Desmaz. PI. Crypt. (Fasc. 41) 2049. 



1850. 



Uredo miniata Lini Pers. Syn. Fung. 216. 1901. 

 On Linaceae: 



Linum Lewisii Pursh — Blue Mts., 7,000-8,000 ft., eastern Oregon, 

 1897 (from phanerogamic specimen in Gray Herb. Harvard Univ.); 

 Hermiston, Umatilla Co., May 12, 1915, 2664. 



Arthur (Jour. Myc. 13: 207. 1907) has shown this species to be 

 autoecious. He sowed basidiospores from Linum iisitatissimum on 

 the same host and on L. Lewisii and obtained the development of 

 pycnia and aecia. 



18. Melampsora occidentalis Jackson, Phytopath. 7: 354. 1917. 

 On Salicaceae: II, III. 



Populus tridwcarpa Nutt. — Corvallis, Sept. 1909, io6g, Oct. 15, 

 1912, 1024 (type), March 12, 1916, G. B. Posey; Trail to Sulphur 

 Springs, Benton Co., Nov. 2, 1914, 336g; Scott's, N. of Fort Klamath, 

 Klamath Co., Sept. 20, 191 3, E. P. Meinecke, CrD2; Clatskanie, 

 Columbia Co., Oct. 6, 1914, F. D. Bailey, 3358, Oct. 29, 1914, F. D. 

 Bailey, 3306; Sumpter, Baker Co., Aug. 21, 1915, J. R. Weir, 265; 

 Medical Springs, Union Co., Aug. 1913, J. R. Weir, 117. 



This species differs from all other species of Melampsora on Populus 



