JACKSON: UREDINALES OF OREGON 235 



This study has also shown that the species as here considered 

 is a composite form made up of several distinct physiological races. 



The species is separable from all other American species of Puccinia 

 on Carex by the presence of two pores in the upper part of the rather 

 small (12-19 b/ 16-23 ^) urediniospores and the medium-sized (12-20 

 by 35-50 fi) teliospores. 



The aecia of this species should not be confused with those of 

 P. stipae (cf. 166), which occur on the same generic hosts and other 

 Carduaceae in the west. In P. Asterum the aecia are cupulate, the 

 peridium conspicuous, the spores globoid, nearly colorless and small 

 (11-15 by 13-18 /i). In P. stipae the aecia occur on hypertrophied 

 areas, the individual cups are gall-like and open by a central aperture, 

 the peridium is evanescent, the spores are cinnamon brown, globoid, 

 large (21-26 by 22-29 /")• The aecia of the latter species have not been 

 found in Oregon, but doubtless occur abundantly in the eastern part 

 of the state. 



70. Puccinia Asteris Duby, Bot. Gall. 2: 888. 1830. 

 On Carduaceae: 



Aster conspiciiiis Lindl. — Hilgard, Union Co., July 10, 1914, 1538; 

 Crater Lake, Klamath Co., Sept. 3, 1916, J. R. Weir, 182. 



Aster sp. — Corvallis, Aug. 10, 1911, F. D, Bailey, 1175, May i, 

 1915. 3050; Austin, Grant Co., June 1913, J. R. Weir, 102. 



71. Puccinia atro-fusca (Dudley & Thompson) Holway, Jour. Myc. 



10: 228. 1904. 



Uromyces atro-fiiscus Dudley & Thompson, Jour. Myc. 10: 55. 

 1904. 

 On Cyperaceae: 



Carex Douglasii Boot. — Enterprise, Wallowa Co., July 24, 1897, 

 E. P. Sheldon (from Phan. spec. 8634). 



This species possesses amphispores which were first mistaken for 

 the teliospores of a Uromyces. It may be distinguished from other 

 Carex rusts by the presence of the amphispores together with the 

 normal urediniospores, the latter are 20-26 /x long and thin walled, 

 1.5-2 jx thick. The aecial connection is unknown. It is known only 

 from the Rocky mountain and Pacific coast regions. 



72. Puccinia Balsamorriiizae Pk. Bull. Torrey Club 11: 49. 1884. 

 Trichohasis Balsamorrhizae Pk. Bot. Gaz. 6: 276. 1881. 



On. Carduaceae: 



Bahamorrhiza deJtoidea Nutt. — Corvallis, July 29, 1914, 1472; 

 Hermiston, Umatilla Co., May 12, 1915, 2663. 



Bahamorrhiza sagittata (Pursh) Nutt. — Hood River, Aug. 11, 1909, 

 3186; Durfur, Wasco Co., June 19, 1914, 1836. 



