110 15. GRAPHIDACEAE [53. Graphis 



black, the proper exciple black, covered laterally by a more or less disappearing 

 thalloid one; hypothecium hyaline; spores ellipsoid, 6-12-septate, 16-50 X 7-9.5 it. 

 On trees, Florida. 



18. Graphis Celtidis Mull. Arg., Bull. Herb. Boiss. 3:45. 1895. 



Thallus very thin, smooth to slightly and obscurely rough, finally chinky, 

 greenish gray; apothecia short to longer, and very narrow, 1-4 X 0.15-0.2 mm., 

 immersed to subsuperficial, straight to curved or flexuous, infrequently and spar- 

 ingly branched, the disk closed to slightly open and brownish black or slightly 

 grayish pruinose, the exciple brownish black, covered laterally by a thalloid one; 

 spores ellipsoid, 7-11-septate, 24-38 X 8-10 /x. 



On trees, Louisiana and Florida. 



19. Graphis intertexta Mull. Arg., Bull. Herb. Boiss. 3:45. 1895. 



Thallus very thin, becoming minutely rough and chinky, said to be sometimes 

 granulose, brownish yellow, fading to lighter shades; apothecia short and narrow, 

 0.5-2 X 0.25-0.4 mm., immersed often in groups, straight to curved or slightly 

 flexuous, seldom branched, the disk sunken, closed or slightly open and grayish 

 white, the exciple and the hypothecium hyaline, the former poorly developed and 

 covered by a raised thalloid one; spores 6-8, oblong-ellipsoid, 9-16-septate, 

 18-44 X 6.5-8.5 /a. 



On trees, Louisiana and Florida. 



20. Graphis leucopepla Tuck., Syn. N. A. Lich. 2:126. 1888. 



Thallus thin, becoming slightly rough and scurfy, greenish gray, varying to- 

 ward olive-green; apothecia short, oblong, and narrow, 0.5-1 X 0.2-0.3 mm., 

 partly immersed, straight to slightly curved, the disk closed to open and whitish 

 powdery, the exciple and hypothecium pale, the former rudimentary but some- 

 times blackish above, covered by a thalloid one; spores 4-8, oblong-ellipsoid and 

 slightly constricted at the septa, 13-20-septate, 28-47 X 6-8 fx. 



On trees, Florida. 



21. Graphis Poitaeoides Nyl., in Tuck., Syn. N. A. Lich. 2:126. 1888. 

 Thallus thin, smooth to slightly granulose, pale greenish gray; apothecia short to 



elongated, but narrow, 1-4 X 0.15-0.25 mm., immersed to partly immersed, curved 

 to flexuous, rarely becoming somewhat branched, finally radiately grouped, the 

 disk closed or rarely opening narrowly and pale, the proper exciple pale to brown- 

 ish, covered laterally and often above by a strong thalloid one; hypothecium 

 hyaline; spores 4-8, long-ellipsoid, 11-21-septate, 36-90 X 8-13 /a. 

 On trees, Florida, Georgia, and Texas. 



22. Graphis elegans (J. E. Smith) Ach., Syn. Meth. Lich. 85. 1814. 

 Opegrapha elegans J. E. Smith, in Sowerby, Engl. Bot. 26: pi. 1812. 1807. 

 Thallus thin, smooth to wrinkled and sometimes granular, pale greenish gray 



to whitish or yellowish; apothecia short to elongated, becoming wide, 0.3-5 X 0.35- 

 0.9 mm., subadnate, straight to curved or rarely flexuous, very rarely branched, 

 the disk closed, the exciple black, thick and strongly 1-4 or more times striate, 

 covered laterally by a finally obscure or disappearing thalloid one; hypothecium 

 hyaline; spores usually 8, long-ellipsoid, 7-15-septate, 35-90 X 8-14 /x. 

 On trees, from New Jersey to Florida, and westward to Texas. 



23. Graphis striatula (Ach.) Spreng., Syst. Veg. 4:250. 1827. 

 Opegrapha striatula Ach., Syn. Meth. Lich. 74. 1814. G. duplicata Eschw. 

 Thallus thin, smooth, pale greenish gray to whitish; apothecia becoming long 



and rather narrow, 1-5 X 0.2-0.4 mm., partly immersed; usually curved or flexuous, 

 sometimes 1-3 or 4 times branched, the disk closed, the proper exciple black, 1-3 

 times obscurely striate, covered laterally by a thalloid one; hypothecium hyaline; 

 spores 6-8, 7-15-septate, ellipsoid, 35-52 X 7-10 /x. 

 On trees, South Carolina, Louisiana, and Florida. 





