50. Opegrapha] 15. GRAPHIDACEAE 99 



6. Opegrapha herpetica Ach. var. subocellata Ach., Syn. Meth. Lich. 73. 1814. 



Thallus thin, smooth to slightly rough, becoming chinky, greenish gray to ashy 

 or brownish, limited and sometimes dissected by blackish lines, becoming powdery 

 and sometimes disappearing; apothecia rather short, but of average width, 0.5-1.5 X 

 0.2-0.25 mm., oblong to slightly irregular, immersed in a white, thalloid exciple, 

 scattered or clustered, straight to curved, sometimes 1 or 2 times branched, the 

 disk closed to open, flat, and brownish black, the exciple rather thin; hypothecium 

 medium to dark brown; spores hyaline to finally brownish, ellipsoid-fusiform, 

 3-septate, 20-26 X 4-5 \x. 



On trees, near Sanford, Florida. (The species is reported from temperate re- 

 gions.) 



7. Opegrapha microcyclia Tuck., Proc. Am. Acad. 5:285. 1866. 

 O. myriocarpa Tuck, (non Fee). 



Thallus rather thin, brownish gray, minutely granulose, the granules often 

 heaped, forming a somewhat rough crust; apothecia minute, round to slightly 

 elongated, 0.15-0.25 mm. across, or reaching 0.4 mm. in one direction, adnate, 

 usually numerous, and scattered or clustered, the disk open, concave to flat, brown- 

 ish black, the exciple well developed and of the same color; hypothecium light to 

 darker brown; spores ovoid-dactyloid, 3-septate, 13-15 X 5-6 /x. 



On trees, New Hampshire and Massachusetts. 



8. Opegrapha Candida Mull. Arg., Bull. Herb. Boiss. 3:42. 1895. 



Thallus thin, smooth, and white, becoming powdery; apothecia rather short 

 and narrow, 0.3-2.5 X 0.12-0.17 mm., the ends obtuse, slightly immersed to ad- 

 nate, scattered, straight to curved, infrequently and sparingly branched, the 

 disk closed, the exciple black and moderately thick; hypothecium brownish black; 

 spores ovoid-finger-shaped, 3-septate, 11-13 X 4-5 fx. 



On bark of Liriodendron, Florida. 



9. Opegrapha saxicola Ach., Syn. Meth. Lich. 71. 1814. 



Thallus thin, smooth to scurfy or granulose, rarely tending to disappear; apo- 

 thecia rather short and wide, sometimes irregular, 0.3-2 X 0.3-0.5 mm., oblong- 

 ellipsoid, adnate, scattered or clustered, straight to infrequently curved, often and 

 variously branched, the disk closed to open and concave to flat, dull or brownish 

 black, the exciple black; hypothecium brownish black; spores hyaline to brownish, 

 ellipsoid to ovoid, 3-septate, 18-28 X 5-7 /t. 



On rocks, California. 



10. Opegrapha calcarea Turn., in Sowerby, Engl. Bot. 25:1790. 1807. 

 O. chevallieri Leight. pr. p. 



Thallus thin to moderately thick, smooth to slightly rough, scurfy or chinky, 

 pale greenish gray to whitish or yellow, sometimes breaking into powdery condi- 

 tions and finally disappearing; apothecia of moderate length and width, 0.5-2 X 

 0.2-0.3 mm., oblong-ellipsoid, adnate, scattered to radiately clustered, soon curved 

 or flexuous, infrequently branched, the disk closed to open, flat, black, the exciple 

 moderately thick and black; hypothecium brownish black; spores hyaline to 

 brownish, ellipsoid, 3-septate, 12-16 X 3.5-5 /x. 



On rocks, southern California. 



11. Opegrapha filicina Mont., in Sagra, Hist. Nat. Cub. Bot. 184. pi. 9, f. 1. 



1835-42. 



Opegraphella filicina (Mont.) Mull. Arg. Fouragea filicina (Mont.) Trev. 



Thallus within the substratum and indicated at the surface by a greenish, green- 

 ish gray, or finally brownish coloration; apothecia becoming somewhat long, but 

 remaining very narrow, 0.2-1.5 X 0.1-0.2 mm., the ends usually obtuse, adnate, 

 scattered to sometimes rather loosely grouped, straight to curved or infrequently 

 flexuous, rarely 1-2 or 3 times branched, the disk closed and finally indicated by 



