210 33. LECIDEACEAE [119. Lecidea 



98. Lecidea humosa (Ehrh.) Rohling, Deutschl. El 3:36. 1813. 



Lichen humosus Ehrh., in Hoffm., Deutschl. Fl. 191. 1796. L.uliginosa var. 

 humosa (Ehrh.) Ach. L.humicola (Ach.) Fink, Ohio Biol. Surv. 2:339. 

 1921 by error in spelling. 

 Thallus very minutely and inconspicuously granulose, brownish black, evanes- 

 cent; apothecia minute to small, 0.2-0.4 mm. across, scattered or clustered, the 

 disk flat to convex, dark brown to black, the exciple thin, of the same color, finally 

 disappearing; hypothecium dark brown; spores oblong-ellipsoid, 9-15X5-7/*.. 

 On soil and shaded rock, moist woods, Ohio and Kentucky. 



99. Lecidea cyrtidia Tuck., Proc. Am. Acad. 12:181. 1877. 



Thallus of minute granules, inconspicuous, scattered to crowded, scurfy, green- 

 ish gray to olive-green, frequently widespread; apothecia minute, 0.2-0.5 mm. 

 across, closely adnate, the disk flat to convex, black, the exciple black, thick, soon 

 disappearing; hypothecium blackish brown; spores ovoid-ellipsoid, 5-9 X 2-4 /a. 



On rocks, from New England to Delaware, and westward to Illinois and Minne- 

 sota. 



100. Lecidea sylvicola Flot., Lich. Sil. Exsicc. no. 171. 1829. 



Thallus granulose, greenish gray to olive-brown or darker, or the minute, 

 flattened to hemispherical granules passing into a thin, continuous or scattered, 

 scurfy, verrucose or subareolate crust; apothecia minute to small, 0.2-0.5 mm. 

 across, immersed to more commonly adnate, the disk flat to convex, dark brown 

 to black, the exciple black, soon disappearing; hypothecium blackish brown or 

 bluish black; spores ellipsoid, 5-9 X 2.5-4 ju.. 



On rocks, Ohio and Minnesota. 



101. Lecidea myriocarpoides Nyl., Flora 48:355. 1865. 

 Biatora myriocarpoides (Nyl.) Tuck. 



Thallus rather thin, granulose, somewhat scurfy, widespread, scattered or dis- 

 appearing, olive-brown, the granules minute, irregular, somewhat flattened to 

 rarely hemispherical; apothecia minute to small, 0.15-0.4 mm. across, adnate, the 

 disk flat to convex and swollen, dark brown to black, the exciple thin, soon dis- 

 appearing; hypothecium brown to blackish brown; spores ellipsoid, 6-9X3-5//.. 



On old wood, in eastern United States, Illinois, Iowa, Minnesota, and Cali- 

 fornia. 



102. Lecidea xanthococcoides Zahlbr., Bull. Torr. Club 27:644. 1900. 

 Thallus thin, grayish to yellowish brown, wrinkled-granulose to verrucose; 



apothecia minute to small, 0.3-0.4 mm. across, sessile, the disk slightly concave 

 to finally convex, black, the exciple thin, black, finally disappearing; hypothecium 

 dark brown; spores ovoid to ovoid-oblong, 12-15 X 5.5-6 //.. 

 On trees, San Bernardino Mountains, California. 



103. Lecidea albocaerulescens (Wulf.) Ach., Meth. Lich. 52. 1803. 



Lichen albocaerulescens Wulf., in Jacq., Coll. Bot. 2:184. pi. 15, f. 1. 1788. 

 L. albocaerulescens var. flavocaerulescens Schaer. L. hebescens Nyl. 



Thallus smooth or somewhat rough, ashy to greenish gray or olive-green, more 

 or less chinky or becoming obscurely small-areolate, continuous, moderately thick; 

 apothecia small to large, 0.4-1.5 mm. across, immersed to adnate, round to 

 irregular, the disk usually flat, black or brownish black, commonly more or less 

 whitish pruinose, the exciple black, rarely disappearing; hypothecium dark brown 

 to blackish; spores ellipsoid, 15-24 X 7-10 //,. (Plate 16 b.) 



On rocks, northeastern United States, southward to Florida and Alabama at 

 high elevations, westward to Illinois and Missouri, and reappearing in Washington. 

 (Thallus sometimes tinged red by iron.) 



