112. Pannaria] 30. PANNARIACEAE 175 



7. Parmeliella plumbea (Lightf.) Mull. Arg., Bull. Herb. Boiss. 2 : app. 1. 44. 



1894. 



Lichen plumbeus Lightf., Fl. Scot. 2:826. pi. 26. 1777. Pannaria plumbea 

 (Lightf.) Bory. 



Thallus small to middle-sized, round, yellowish brown to brownish lead-colored, 

 composed of imbricated lobules toward the center, irregularly lobed toward the 

 circumference, the lobes radiately wrinkled, with round or round-crenate margins; 

 bearing pale to bluish black rhizoids below; apothecia small to middle-sized, 0.6- 

 2 mm. across, subsessile, the disk flat to convex, reddish brown to blackish, the 

 proper exciple thin, lighter colored and disappearing; spores ellipsoid, 16-24 X 

 6-9 fi. 



On trees, Maine and Louisiana. 



8. Parmeliella stellata (Nyl.) Zahlbr., Cat. Lich. Univ. 3:224. 1925. 

 Pannaria stellata Nyl., Ann. Sci. Nat. Bot. IV. 12:295. 1859. Coccocarpia 



stellata (Nyl.) Tuck. 



Thallus composed of minute to small, lead-colored, linear and flattened lobes, 

 many-cleft and radiant at the circumference and becoming densely imbricated 

 toward the center; white below and bearing whitish rhizoids; apothecia minute to 

 small, 0.2-0.6 mm. across, sessile, the disk flat to convex, reddish brown, the 

 exciple thin, reddish brown, bearing minute white rhizoids below, often disappear- 

 ing; spores ellipsoid, 5-10 X 3-4.5 ti. 



On trees, South Carolina, Florida, and Alabama. 



9. Parmeliella ruderatula (Nyl.) Hasse, Cont. U.S. Nat. Herb. 17:79. 1913. 

 Pannularia ruderatula Nyl., in Hasse, Lich. South. Calif. 10. 1898. 



Thallus composed of minute to small, dark yellowish brown, imbricated, con- 

 cave to slightly convex squamules, with minutely crenulate margins, upon an 

 obscure, brownish black hypothallus; apothecia small to middle-sized, 0.6-1 mm. 

 across, sessile, the disk flat, brownish to purplish brown, the proper exciple thin, 

 brownish to brown, rarely disappearing; asci inflated-clavate; hypothecium hyaline 

 to pale straw-colored; spores oblong-ellipsoid, 17-21 X 5.5-7 /x. 



On rocks, southern California. 



112. Pannaria Del., in Bory, Diet. Class. Hist. Nat. 13:20. 1828. 



Thallus distinctly foliose or more commonly small and squamulose, quite 

 closely attached to the substratum by rhizoids, or resting upon a more or less dis- 

 tinct hypothallus, differentiated into a well-developed, distinctly cellular upper 

 cortex, distinct algal and medullary layers and a thin, distinctly cellular lower 

 cortex, or in the squamulose conditions appearing to be plectenchymatous through- 

 out with algal cells scattered throughout except in the outer cells of the cortex; 

 apothecia minute to small or middle-sized, adnate to sessile, the disk concave to flat 

 or convex, red to brown or black, the exciple colored like the thallus, irregular, 

 sometimes disappearing; hypothecium hyaline to brown; hymenium hyaline or 

 brownish above; paraphyses rarely branched; asci clavate; spores 8, hyaline, oblong 

 to ellipsoid or ellipsoid-pointed, non-septate. 



The algal host is Nostoc. 



A. Apothecia not more than 0.5 mm. across 



B. Spores 9-13 X 4-5.5 m 1. P. granatina 



B. Spores 20-33 X 2-3 /x 3. P. sonomensis 



A. Apothecia more than .05 mm. across 



B. Hypothallus dark, more or less distinct 



C. Thallus plainly foliose, the lobes marginally ascending 



D. Thallus densely sorediate 6. P. rubiginosa lanuginosa 



D. Thallus smooth to minutely granulose 6. P. rubiginosa 



C. Thallus squamulose, closely adnate 



D. The margins white-powdery 4. P. leucosticta 



D. The margins not white-powdery 5. P. mariana 



