154. Parmelia] 39. PARMELIACEAE 325 



concave, light to darker brown, the exciple subentire, finally bearing coralloid 

 branchlets; spores ellipsoid, 10-14 X 5.5—9 /x. 

 On trees, Georgia, Florida, and Louisiana. 



10. Parmelia latissima Fee, Suppl. Essai Crypt. 119. pi. 38, f. 4. 1837. 

 P. perlata var. latissima Mont. 



Thallus middle-sized to large, adnate, whitish to greenish gray, naked or bearing 

 coralloid branchlets, the lobes short, wide, sparingly branched, the margins round, 

 entire to wavy; black below, brown toward the margins, rhizoids small and scat- 

 tered, black; apothecia small to middle-sized, 3-8 mm. across, subsessile, the disk 

 concave, chestnut-brown, the exciple with entire or irregular margin, sometimes 

 bearing coralloid granules; spores ellipsoid, 22-34 X 11-20 /x. 



On trees and fences, South Carolina, Georgia, Florida, Louisiana, and Texas. 



var. sorediata Nyl.; Hue, Nouv. Arch. Mus. III. 2:282. 1890. 

 The margins of the lobes sorediate, and coralloid branchlets rarely if ever 

 present. 



On trees, Florida. 



11. Parmelia crinita Ach., Syn. Meth. Lich. 196. 1814. 

 P. crinita var. pilosella (Hue) Merrill. 



Thallus becoming large, rather loosely adnate, lighter to darker greenish gray, 

 densely covered with granules or coralloid branchlets, the broad, wrinkled lobes 

 often ascending slightly, with inconspicuously ciliate, irregular or crenate margins; 

 black below and clothed with strong rhizoids of the same color, often brown toward 

 the margins; apothecia rare, subpedicellate, small to middle-sized, 4-12 mm. across, 

 the disk deeply concave, chestnut-brown, the exciple irregular or crenate, some- 

 times bearing cilia or coralloid branchlets; spores ellipsoid, 17-22 X 9-15 p. 



On trees and rarely on rocks, throughout the United States. 



12. Parmelia cristifera Tayl., in Hook., Journ. Bot. 6:165. 1847. 



Thallus middle-sized to large, adnate, greenish gray to whitish, the lobes short, 

 broad, subimbricate toward the center, the margins raised and sometimes bearing 

 globose soredia, or these fusing into soralia; black below and bearing few rhizoids 

 toward the center, brownish and smooth toward the edges; apothecia small to 

 middle-sized, 3-8 mm. across, subsessile, the disk concave, chestnut-brown, the 

 exciple thin, colored like the thallus, becoming wavy; spores ellipsoid, 20-30 X 

 10-18 fx. 



On trees, Florida. 



13. Parmelia olivaria (Ach.) T. Fries, Lich. Scand. 1:112. 1871. 

 P. perlata var. olivaria Ach., Meth. Lich. 217. 1803. 



Thallus middle-sized, loosely adnate, smooth, ashy to greenish gray or yellow- 

 ish brown, the lobes wide and short, ascending and often bearing white soredia 

 at least toward the entire to wavy-crenate margins; black below and bearing scat- 

 tered black rhizoids; apothecia middle-sized, 3-7 mm. across, subsessile, the disk 

 concave to flat, chestnut-brown, the exciple entire, sometimes sorediate; spores 

 ellipsoid, 14-18 X 7-12 fx. 



On trees, Rockland, Maine, sterile, and doubtfully admitted. 



14. Parmelia perlata (L.) Ach., Meth. Lich. 216,217. 1803. 



Lichen perlatus L., Syst. Nat. ed. 12. 712. 1770. P. perlata var. ciliata (Lam. 

 & DC.) Duby. 



Thallus middle-sized to large, adnate, pale or darker greenish gray, the lobes 

 rather large, not much elongated, often more or less branched, often imbricated, 

 slightly ascending toward the often white-sorediate, rarely ciliate, wavy to crenate 

 margins; black below, brown toward the margins, usually bearing scattered black 

 rhizoids; apothecia middle-sized, 4-12 mm. across, the disk concave, chestnut- 

 brown, the exciple entire; spores short-ellipsoid, 10-17 X 6-10 fx. 



On rocks and rarely on trees, throughout northern United States, especially in 

 the mountain areas. 



