172. Rinodina ] 43. BUELLIACEAE 379 



18. Rinodina tephraspis (Tuck.) Herre, Proc. Wash. Acad. 12:250. 1910. 

 Lecanora tephraspis Tuck., Am. Journ. Sci. II. 25:425. 1858. R. sophodes var. 



tephraspis Tuck. 



Thallus moderately thick, rough, composed of crenulate or often warty, crowded, 

 brownish gray to ashy areoles; apothecia small to middle-sized, 0.5-1.2 mm. across, 

 adnate, irregular, the disk flat to convex, black, the exciple thin, colored like the 

 thallus, becoming crenulate; hypothecium hyaline to cloudy; spores ellipsoid to 

 oblong-ellipsoid, 16-22X7-10/*. 



On rocks, South Carolina, Minnesota, Iowa, and California. 



19. Rinodina destitula (Nyl.) Zahlbr., Cat. Lich. Univ. 7:510. 1931. 

 Lecidea destitula Nyl.. Lab. et Sing. 41. 1891. 



Thallus very thin, minutely areolate, grayish white, soon disappearing; apothecia 

 small, 0.3-0.6 mm. across, adnate, round to irregular and clustered, the disk flat, 

 black, the exciple prominent, colored like the thallus; hypothecium brownish; spores 

 ellipsoid, 20-23 X 8-11/*. 



On rocks, Illinois. 



20. Rinodina euryspora Zahlbr., Bryologist 18:23. 1915. 



Thallus thin to moderately thick, chinky to areolate, the areoles small, concave, 

 dirty yellowish or brownish; apothecia minute to small, 0.2-0.6 mm. across, adnate 

 to sessile, the disk flat, black or whitish pruinose, the exciple rather thick, colored 

 like the thallus, becoming crenulate; hypothecium hyaline to yellowish; spores 

 ovoid-ellipsoid, 12-16 X 6-10/*. 



On rocks, southern California. 



21. Rinodina ocellata (Hoffm.) Arm, Flora 67:318. 1884. 



Verrucaria ocellata Hoffm., Plant. Lich. 1:92. pi. 20, f. 2. 1790. R.lecanorina 

 Mass. R. iowensis Zahlbr. 



Thallus rough, moderately thick, composed of flat to slightly convex, small 

 to middle-sized, greenish gray to green or ashy brown, scattered or continuous 

 areoles; apothecia minute to small, 0.3-0.8 mm. across, 1 or more immersed in 

 each areole or becoming superficial, round to more or less irregular, the disk flat 

 to slightly convex, blackish brown to black, the exciple thin, colored like the 

 thallus, rarely becoming wavy; hypothecium hyaline to cloudy; spores oblong 

 to oblong-ellipsoid, 15-21 X 8-10/*. 



On rocks, Minnesota and Iowa. 



22. Rinodina ochrocea Willey; Hedrick, Mycologia 26:165. 1934. 



Thallus thin, chinky-areolate, the areoles minute to small, irregular, continu- 

 ous, yellowish gray to brownish; apothecia minute to small, 0.2-0.4 mm. across, 

 immersed to adnate, more or less crowded, round to irregular, the disk concave, 

 black, the exciple rather thick, colored like the thallus, more or less uneven; 

 hypothecium hyaline; spores oblong-ellipsoid, 20-25X9-11/*. 



On rocks, South Carolina. 



23. Rinodina biatorina Koerb., Par. Lich. 76. 1865. 



Thallus thin, composed of minute to small, flat to convex, greenish gray to 

 ashy squamules, continuous or scattered upon an inconspicuous black hypothallus ; 

 apothecia minute, 0.1-0.3 mm. across, adnate, the disk flat to slightly convex, 

 black, the exciple thin, colored like the thallus, rarely disappearing; hypothecium 

 hyaline to yellowish; spores ovoid-ellipsoid, 14-20X7-9/*. 



On rocks, Maryland. 



24. Rinodina angelica Stizenb.; Hasse, Bull. Torr. Club 24:447. 1897. 

 Thallus chinky to coarsely areolate or rarely squamulose, greenish gray to 



grayish flesh-colored, sometimes becoming lobed toward the circumference; apo- 

 thecia small to middle-sized, 0.35-1 mm. across, partly immersed to adnate, the 

 disk flat to slightly convex, dull black or rarely grayish pruinose, the exciple thin 



