174. Physcia] 44. PHYSCIACEAE 383 



2. Pyxine Eschweileri (Tuck.) Vainio, Lich. Bresil 1:156. 1890. 



P. cocoes var. Eschweileri Tuck., Obs. Lich. 4:167. 1877. P.sorediata var. 

 Eschweileri Tuck. 



Thallus small to middle-sized, greenish gray to ashy, smooth to slightly wrinkled, 

 bearing soredia or rarely coralloid branchlets, the lobes rather short, imbricated, 

 the margins becoming crenate; brownish black below, bearing numerous brownish 

 black rhizoids; apothecia middle-sized, 0.7-2 mm. across, sessile, round to slightly 

 irregular, the disk flat to convex, black or obscurely grayish pruinose, the exciple 

 thin to rather thick, becoming black; hypothecium dark brown; spores ellipsoid, 

 3-septate, 14-17 X 5-7 /x. 



On trees, Florida. 



3. Pyxine cocoes (Swartz) Nyl., Mem. Soc. Sci. Nat. Cherb. 5:108. 1857. 

 Lichen cocoes Swartz, Fl. Ind. Occ. 146. 1788. P. cocoes var. caesiopridnosa Tuck. 

 Thallus small to middle-sized, smooth, greenish gray to ashy, bearing whitish 



soredia, the lobes elongated, subdichotomously branched, imbricated, the margins 

 entire to slightly crenate; black below, bearing short, brownish black rhizoids; 

 white within; apothecia small, 0.8-1.5 mm. across, the disk flat to slightly convex, 

 black or grayish pruinose, the exciple thin to moderately thick, becoming black; 

 hypothecium dark brown; spores ellipsoid, 1-septate, 15-22 X 6-9 fi. 

 On trees, Florida and Louisiana. 



4. Pyxine Meissneri Tuck., in Nyl., Syn. Meth. Lich. 2:1. 1860. 



Thallus small, smooth to slightly wrinkled, ashy to whitish, the lobes rarely 

 elongated, commonly imbricated, rarely bearing whitish soredia, the margins cre- 

 nate; black below, with minute black rhizoids; whitish to yellowish within; apothe- 

 cia small, 0.8-1.5 mm. across, sometimes clustered, the disk flat to slightly convex, 

 black, the exciple thin, wavy, becoming black; hypothecium dark brown; spores 

 ellipsoid, 1-septate, 15-22 X 6-9 /a. 



On trees, Florida. 



5. Pyxine picta (Swartz) Tuck., Proc. Am. Acad. 4:398. 1862. 



Lichen pictus Swartz, Fl. Ind. Occ. 146. 1788. P. picta var. applanata (Fee) 

 Stizenb. P. picta var. erythrocardia Tuck. 



Thallus small to middle-sized, closely adnate, smooth to wrinkled, ashy or 

 whitish, often passing into a warty crust toward the center, the lobes somewhat 

 elongated, subdichotomously branched, commonly imbricated, sometimes bearing 

 white soredia, the margins crenate; black below, with few black rhizoids; whitish 

 to rarely yellowish orange within; apothecia small, 0.75-2 mm. across, sessile, the 

 disk flat, brownish black to black or sometimes pruinose, the exciple thin, becoming 

 black; hypothecium dark brown; spores ellipsoid, 1-septate, 15-23 X 7-9 /x. 



On trees, from South Carolina to Florida, and westward to Texas. 



6. Pyxine Frostii Tuck., Syn. N. A. Lich. 1:79. 1882. 



Squamaria Frostii Tuck., Am. Journ. Sci. II. 25:425. 1858. Lecanora Frostii 

 Tuck. 



Thallus small to middle-sized, closely adnate, smooth, greenish gray to cream- 

 colored, usually bearing scattered white soredia, the lobes subpalmately divided, 

 imbricated, the margins crenate; black below, bearing minute brownish black 

 rhizoids; white within; apothecia small, 0.5-0.8 mm. across, sessile, the disk flat, 

 black, the exciple thin, crenate; hypothecium dark brown; spores oblong-ellipsoid, 

 1-septate, 14-20 X 5-7 /x. 



On granite, New England and Virginia. 



174. Physcia Ach., Kgl. Vet. Akad. Nya Handl. 15:252. 1794. 



Thallus foliose, rarely becoming crustose, smooth to rough, more or less lobed, 

 often sorediate, rarely bearing coralloid branchlets, differentiated into well-devel- 

 oped, plectenchymatous upper and lower cortices of vertical extending hyphae, the 



