172. Rinodina] 43. BUELLIACEAE 381 



obtuse, rarely disappearing; hypothecium hyaline; spores short-ellipsoid, 9-12 X 



4.5-7.5 fi. 



On rocks, throughout the United States except in the extreme south. 



31. Rinodina novomexicana B. de Lesd., Bull. Soc. Bot. de France 613,614. 



1930. . 



Thallus moderately thick, smooth to rough, composed of minute to small, ir- 

 regular, crowded, flat to convex, greenish yellow to ashy areoles, becoming radiately 

 lobed toward the circumference; apothecia small to middle-sized, 0.35-0.8 mm. 

 across, partly immersed to adnate, irregular, sometimes crowded, the disk flat to 

 slightly convex, black, the exciple thin, colored like the thallus, sometimes dis- 

 appearing; hypothecium hyaline to brownish; hymenium hyaline; spores ovoid to 

 ovoid-ellipsoid, 8-13 X 4-7 fi. 



On rocks, New Mexico. 



var. caesia B. de Lesd., Bull. Soc. Bot. de France 614. 1930. 

 Apothecia larger, reaching 1.2 mm. across, the disk grayish pruinose. 

 On rocks, New Mexico. 



32. Rinodina chrysomelaena (Ach.) Tuck., Gen. Lich. 123. 1S72. 

 Lecanora chrysomelaena Ach., Syn. Meth. Lich. 148. 1814. 



Thallus squamulose, the squamules yellow, flat to slightly convex, minutely 

 lobed, scattered upon a thin, blackish hypothallus; apothecia small, 0.3-0.8 mm. 

 across, the disk slightly concave to flat, dark reddish brown to black, the exciple 

 thick, colored like the thallus, becoming wrinkled and flexuous; hypothecium yel- 

 lowish to brownish; spores ellipsoid, 18-30 X 10-14 [x. 



On rocks, Massachusetts, North Carolina, Georgia, Pennsylvania, Tennessee, 

 and Montana. 



33. Rinodina phaeocarpa (Sommerf.) Vainio, Term. Fiiz. 22:302. 1899. 

 Lecidea phaeocarpa Sommerf., Suppl. Fl. Lapp. 159. 1826. R.nimbosa (E. 



Fries) T. Fries. 



Thallus squamulose, pale yellowish to dull brown or grayish pruinose, the 

 squamules more or less crowded and finally running together, the central ones 

 sometimes reduced and round, the marginal ones lobed, the lobes often crenate 

 and imbricate; apothecia small to middle-sized, 0.5-1.2 mm. across, partly im- 

 mersed, the disk flat to slightly convex, brownish black or rarely grayish pruinose, 

 the exciple thick, colored like the thallus; hypothecium hyaline; spores ellipsoid, 

 sometimes slightly constricted at the septum, 14-20 X 7-10 /x. 



On soil, Colorado. 



34. Rinodina thysanota Tuck., Proc. Am. Acad. 12:174. 1877. 

 Lecanora thysanota (Tuck.) Hasse. 



Thallus closely adnate, brownish green, warty-areolate, radiately lobed to- 

 ward the circumference; apothecia small to middle-sized, 0.5-0.9 mm. across, 

 sessile, the disk flat, blackish brown, the exciple thick, colored like the thallus; 

 hypothecium hyaline to yellowish; spores oblong-ellipsoid, 9-13 X 5-7 /x. 



On rocks, Nevada, Arizona, Oregon, and California. 



35. Rinodina radiata Tuck., Proc. Am. Acad. 12:173. 1877. 



Buellia radiata Tuck., Lich. Calif. 25, 26. 1866. R. radiata f. fimbriata Tuck. 

 R. radiata f. lactea Hasse. 



Thallus thin to moderately thick, closely adnate, somewhat chinky, composed 

 of minute to small, greenish gray to ashy or whitish, flat to convex, continuous 

 areoles, becoming radiately lobed toward the circumference, more or less bordered 

 by a thin black hypothallus; apothecia small to middle-sized, 0.4-1 mm. across, 

 partly immersed to adnate, crowded toward the center of the thallus, the disk flat 

 to slightly convex, dull black or more or less densely whitish pruinose, the exciple 



