LICHENS OF THE STATE OF WASHINGTON 179 



1931, 1684. Columbia Co.: New Hope, 1500 ft., 1931, 1566; Dayton, 1700 

 ft., 1940, 2729. Klickitat Co.: Goldendale, 1909, Foster 1155 QN)._ 

 A common species east of the Cascades. It is abundantly white pruinose. 



7. Physcia stellaris (L.) Nyl. Act. Soc. Linn. Bordeaux 21 :307. 1856. 

 Lichen stellaris Linn. Sp. PL 1144. 1753. 



Thallus white, pearl gray (R), or grayish olive (R), foliose, orbiculate- 

 stellate, appressed, lobes narrow, usually elongated, much divided, rather 

 convex, growing close together, but usually distinct, slightly pruinose, 

 toward the tips, margin entire or crenate, surface smooth at the tips but 

 rugose toward the center, often breaking up into a crust in the center, 

 medulla white ; below white or pale gray with concolorous rhizoids. Apo- 

 thecia numerous, 1.0-5.0 mm. in diameter, round or slightly angular, 

 sessile; disk dark brown or black, usually pruinose, concave to convex; 

 thalline margin thick, persistent, entire or crenate; hypothecium hyaline; 

 spores brown, oblong-ellipsoid, 1-septate, 14.0-23.1 x 6.6-11.0 /x. Upper 

 cortex yellow with KOH. 



On trees and rocks : Pacific Co. : Long Beach, 1940, 2757. Chelan Co. : 

 Merritt, 2186 ft., 1931, 1070; Rainbow Trail, 3500 ft., 1931, 1259. Yakima 

 Co. : Satus Road, 1054 ft., 1931, 1674. Ferry Co. : Republic, 2650 ft., 1931, 

 1408. Clallam Co.: Sequim, 1916, /. M. Grant 835 (F) ; Port Angeles. 

 1914, Foster 2659 (W). Grays Harbor Co.: Westport, 1908, Foster 725 

 (W). Whitman Co.: Pullman, 1900, Beattie 26 (F). 



A common lichen rather widely distributed over the state. It is easily 

 distinguished from other species of Physcia by the abundant apothecia. 



8. Physcia tribacia (Ach.) Nyl. Flora 57:48. 1874. 

 Lecanora tribacia Ach. Lichenogr. Univers. 415. 1810. 



Thallus white, grayish-white, or pearly gray (R), foliose, somewhat 

 orbicular, rather small but these small clusters are inclined to grow to- 

 gether, loosely adnate, lobes much divided, usually short, sometimes becom- 

 ing long, branched, imbricated, with a strongly ascending, much dissected, 

 granulose, finally sorediate margin, sometimes forming a crust in the cen- 

 ter; below white becoming light buff (R), with a few scattered concolorous 

 rhizoids. Apothecia rare, 1.0-1.5 mm. in diameter, sessile to subsessile; disk 

 brownish black to black, concave to flat, usually densely pruinose, thalline 

 margin entire or crenulate ; hypothecium hyaline; spores brown, oblong- 

 ellipsoid, 1-septate, 15.0-18.2 x 7.0-9.9 ;u. Upper cortex yellow with KOH. 



On trees and rocks: Chelan Co.: butte near Chelan, 2000 ft., 1931, 

 1350. Okanogan Co. : butte near Twisp, 1700 ft., 1931, 1461. 



