204 33. LECIDEACEAE [ 119. Lecidea 



var. theioplaca (Tuck.) Zahlbr., Cat. Lich. Univ. 3:664. 1925. 

 L. enter olenca var. theioplaca Tuck., Gen. Lich. 179. 1872. 

 Thallus thicker, rough, chinky to warty, pale yellowish or at least tinged with 

 yellow; hypothecium yellow to blackish. 



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



60. Lecidea torquens Mull. Arg., Hedwigia 34:141,142. 1895. 



Thallus very thin, smooth to sometimes slightly rough, greenish gray to ashy; 

 apothecia minute, 0.1-0.25 mm. across, adnate, sometimes clustered, the disk flat 

 to convex, brownish black to black, the exciple dull blackish, thin, indistinct, and 

 evanescent; hypothecium hyaline to brownish; spores minute, ellipsoid, 7-9 X 

 2—3 ft. 



On old wood, Illinois. 



61. Lecidea virginiensis Nyl., Bot. Gaz. 22:333. 1896. 



Thallus thin, smooth, becoming chinky and finally areolate, greenish gray to 

 dull yellow; apothecia minute, 0.2-0.5 mm. across, subsessile, the disk flat to 

 convex, brownish black to black, the exciple thin, colored like the disk, soon dis- 

 appearing; hypothecium brownish; asci somewhat broadly clavate, the apical wall 

 somewhat thickened; spores oblong-ellipsoid, 9-12X4-5 /a, irregularly arranged. 



On sandstone, West Virginia. 



62. Lecidea cruciaria Tuck., Syn. N. A. Lich. 2:67. 1888. 



Thallus very thin, scurfy, greenish white, intersected by black lines when wet; 

 apothecia middle-sized, 0.5-0.9 mm. across, sessile, the disk flat to slightly convex, 

 black, the exciple black, rather thick, wrinkled or wavy, finally disappearing; 

 hypothecium hyaline to brownish; spores oblong-ellipsoid, 10-20 X 3-6 /x. 



On rocks, Oregon and southern California. 



63. Lecidea lithophila Ach., Syn. Meth. Lich. 14. 1814. 

 L.lapicida var. lithophila Ach., Lich. Univ. 160. 1810. 



Thallus thin, rough and crumbly, chinky-areolate, ashy to whitish, sometimes 

 disappearing; apothecia middle-sized, 0.5-1 mm. across, adnate, frequently clus- 

 tered and angular, the disk slightly concave to slightly convex, black, the exciple 

 pale, finally black, thin, raised, sometimes disappearing; hypothecium hyaline to 

 brownish; spores ellipsoid, 10-14 X 4.5-6.5 ft. 



On rocks, California. 



64. Lecidea pacifica Herre, Proc. Wash. Acad. Sci. 2:264. 1910. 



Thallus thin, minutely rough and becoming chinky or subareolate, ashy white; 

 apothecia middle-sized to large, 0.6-1 mm. across, adnate to subsessile, sometimes 

 clustered and irregular, the disk flat to strongly convex, brownish black, the exciple 

 thin, colored like the disk, disappearing; hypothecium brownish; spores short- 

 ellipsoid, 10-13 X 5-7 ju.. 



On rocks, California. 



65. Lecidea viridescens (Schrad.) Ach., Meth. Lich. 62. 1803. 



Lichen viridescens Schrad., Spic. Fl. Germ. 88. 1794. Biatora viridescens 

 (Schrad.) Mann. 



Thallus granulose, ashy to grayish green, the minute, smooth or deliquescent 

 and powdery granules often forming a thin or rarely thicker crust; apothecia mi- 

 nute to small, 0.2-0.5 mm. across, adnate, frequently clustered or even conglom- 

 erate, the disk flat to convex, black, the exciple thin, pale lead-colored or darker, 

 finally disappearing; hypothecium hyaline to pale brown; spores oblong-ellipsoid, 

 9-12 X 4-5.5 fi. 



On old wood, from New England to Alabama, and westward to Ohio and Min- 

 nesota, and in California. 



