52. Melaspilea] IS. GRAPHIDACEAE 103 



the exciple black and moderately thick; hypothecium brownish black; spores 4, 

 hyaline to brownish, oblong, 15-19 X 5-7 [*. 



On Pertusaria velata, Endocarpon pusillum, and Peltigera aphthosa, Massachu- 

 setts, Ohio, and Minnesota. 



2. Opegraphoidea pulvinata (Rehm.) Fink n. comb. 



Opegrapha pulvinata Rehm., Verh. Zool. Bot. Ver. Wein. 1869:500. 1869. 



Thallus immersed in the substratum and invisible; apothecia minute, round to 

 irregular or oblong and straight, 0.5-0.6 X 0.18-0.3 mm., partly immersed to ad- 

 nate, conglomerate in areas, 1.5-5 mm. across, with many in each area, the disk 

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

 spores brown, oblong-ellipsoid, 15-18X3.5-7/*. 



On Endocarpon miniatum, near Fayette, Iowa. 



3. Opegraphoidea staurothelicola Fink; Hedrick, Mycologia 25:311. 1933. 



Thallus immersed in that of the lichen host and therefore invisible; apothecia 

 short and very narrow, 1.5-2.5 X 0.08-0.1 mm., partly immersed to superficial, 

 scattered and straight to clustered and variously irregular, the disk closed and 

 indicated by an obscure, depressed black line, to rarely open, black, concave to flat, 

 the exciple black; hypothecium thick and dark brown; hymenium pale yellowish 

 brown; spores reaching 8, ellipsoid with one end often more pointed, hyaline to 

 finally brownish, 13-15 X 4.5-5 fi. 



On Staurothele umbrina, Ohio. 



52. Melaspilea Nyl., Act. Soc. Linn. Bord. 21:416. 1856. 



Thallus forming a thin, usually smooth crust, partly or wholly within the sub- 

 stratum, devoid of differentiation into layers; apothecia round to irregular, more 

 or less immersed to adnate or sessile, the disk closed to more or less open, concave 

 to flat or slightly convex, commonly black, the exciple colored like the disk, often 

 irregular; hypothecium hyaline to brownish or brown; hymenium hyaline to 

 brownish above; paraphyses unbranched or rarely somewhat branched; asci clavate 

 to subpyriform, the apical wall sometimes thickened; spores 4 or 6, more com- 

 monly 8, hyaline to brownish, oblong, ellipsoid or slipper-shaped, commonly 1- 

 septate, and constricted at the septum, but rarely 3-7-septate, the cells cylindrical, 

 often unequal. 



The algal host is Trentepohlia. 



A. On trees and old wood, not parasitic on lichens 

 B. Apothecia more or less elongated 

 C. Spores 1-septate 



D. Apothecia reaching 0.8-1.5 mm. in length 



E. Apothecia 1-1.5 mm. in length 1. M. maculosa 



E. Apothecia not more than 0.8 mm. in length 



F. Thallus greenish gray to ashy 5. M. cinerascens 



F. Thallus whitish ... 2. M. constrictella 



D. Apothecia not more than 0.6 mm. in length 



E. Apothecia 0.2-0.4 X 0.1-0.2 mm 3. M. demissa 



E. Apothecia 0.4-O.6 X 0.2-0.4 mm 4. M. deformis 



C. Spores 5-7-septate 6. M. octomera 



B. Apothecia irregular, but not elongated 

 C. Apothecia reaching 0.8-1 mm. across 



D. Spores 12-17X6-8.5/* 10. M. arthonioides 



D. Spores 16-22 X 7-10 m 9. M. amota 



C. Apothecia not more than 0.4 mm. across 



D. Disk open, flat, and somewhat wrinkled 8. M. proximella 



D. Disk closed to narrowly open 7. M. lentiginosula 



A. Parasitic on lichens 



B. Apothecia 0.2-0.4 mm. across 12. M. cupularis 



B. Apothecia 0.3-0.9 X 0.12-0.2 mm 11. M. tribuloides 



