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 by 16-23 w) urediniospores and the medium-sized (12—20 
by 35-50 u) 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 uw). InP. 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 nw). The aecia of the latter species have not been 
found in Oregon, but doubtless occur abundantly in the eastern part 
of the state. 
70. PucctntA ASTERIS Duby, Bot. Gall. 2: 888. 1830. 
ON CARDUACEAE: 
Aster conspicuus Lindl.—Hilgard, Union Co., July 10, 1914, 7538; 
Crater Lake, Klamath Co., Sept. 3, 1916, J. R. Weir, 782. 
Aster sp.—Corvallis, Aug. 10, 1911, F. D. Bailey, 1775, May 1, 
1915, 3050; Austin, Grant Co., June 1913, J. R. Weir, zo2. 
71. PUCCINIA ATRO-FUSCA (Dudley & Thompson) Holway, Jour. Myc. 
TOr+228: 1904" 
Uromyces atro-fuscus Dudley & Thompson, Jour. Myc. 10: 55. 
1904. 
ON CYPERACEAE: 
Carex Douglasit Boot.—Enterprise, Wallowa Co., July 24, 1897, 
E. P. Sheldon (from Phan. spec. S634). 
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 uw long and thin walled, 
1.5-2 wu thick. The aecial connection is unknown. It is known only 
from the Rocky mountain and Pacific coast regions. 
72. PUCCINIA BALSAMORRHIZAE Pk. Bull. Torrey Club 11: 49. 1884. 
Trichobasis Balsamorrhizae Pk. Bot. Gaz. 6: 276. 1881. 
On CARDUACEAE: 
Balsamorrhiza deltoidea Nutt.—Corvallis, July 29, 1914, 1472; 
Hermiston, Umatilla Co., May 12, 1915, 2663. 
Balsamorrhiza sagittata (Pursh) Nutt.—Hood River, Aug. 11, 1909, 
3186; Durfur, Wasco Co., June 19, 1914, 1530. 
