18 LICHENS OF THE STATE OF WASHINGTON 



Thallus dusky or a smoky drab color, thick, tumid, consisting of elevated 

 squamules. Apothecia rounded 2.0-5.0 mm. in diameter, often crowded and 

 confluent, immersed to adnate ; disk black, convex, hypothecium brownish- 

 black; asci 8-spored; spores pale brown to hyaline, ovoid or oblong-ovoid, 

 1-septate constricted in the middle, 10.0-17.0 x 4.5-6.0 fi. 



On moss, rock, or on a thin layer of soil over rock : Washington Terri- 

 tory, Suksdorf 32 (F). 



4. Arthonia impolita (Ehrh.) Borr. in Hook. & Sowerb. Eng. Bot. 1 : tab, 

 2692, f. 1, 1831. Lichen impolita Ehrh., PI. Crypt. Exs. no. 274. 1793. 



Thallus grayish white or pale olive-buff (R), rather thick, smooth or 

 rough, and chinky, crumbling. Apothecia 0.2-1.0 mm. in diameter, circular 

 to elliptical, often clustered, partly immersed to adnate ; disk brown or 

 black, white pruinose, flat ; asci 8-spored ; spores hyaline, ovoid-ellipsoid, 

 3-5-septate, 13.2-16.5 x 4.9-6.0 ix. 



On bark and old wood: San Juan Co.: Turn Island, 1928, 1988; San 

 Juan Island, 1906, Fink 1919. 



5. Arthonia radiata (Pers.) Ach., Kgl. Vet-Akad. Nya Handl. 131, 1808. 

 Opegrapha radiata Pers. Ann. Bot. Usteri, 7:29. 1794. 



Thallus whitish, grayish green, sometimes lacking, occasionally bor- 

 dered by a black line, smooth to slightly rough. Apothecia 0.2-0.9 mm. in 

 diameter, irregularly shaped, often stellate, slightly immersed to adnate; 

 disk black, flat ; asci 8-spored ; spores hyaline, ovoid-ellipsoid, 3-septate, 

 10.5-19.0 X 4.0-5.9 fi. 



On bark: Clallam Co.: near Port Angeles, 1940, 2923. Washington 

 Territory, 1883, Suksdorf 255 (F). 



