63. Enterostigma ] 17. DIRINACEAE 123 



uous, of the same color as the thallus; asci oval-wedge-shaped; spores oblong- 

 ovate, 4-5-septate, 14-18 X 7-9 /*. 



On trees, Santa Catalina Island, California. Spores were uncertain in all 

 the material seen. 



6. Chiodecton subochroleucum Fink; Hedrick, Mycologia 25:313. 1933. 



Thallus thin, yellowish white, smooth to rough and granulose-crumbling; apo- 

 thecia small, 0.4-1 mm. across, scattered or clustered, adnate, round to irregular, 

 the disk flat, rarely black, but much more commonly whitish pruinose, the exciple 

 rarely flexuous, only moderately developed; hypothecium blackish brown, extend- 

 ing under each apothecium into a stroma of the same color; spores 3-septate, 

 ellipsoid to ellipsoid-pointed, 19-27X5-6.5/*. 



On trees, southern California. 



62. Sclerophyton Eschw., Syst. Lich. 14. 1824. 



Thallus crustose, superficial, rudimentary, devoid of differentiation into layers, 

 attached to the substratum by hyphal rhizoids; apothecia clustered in stromata, 

 immersed to superficial, round to elongated, the disk flat, the exciple colored like 

 the disk, well developed or rudimentary ; hypothecium hyaline to brown ; hymenium 

 hyaline or brownish above; paraphyses branched; asci clavate; spores 8, brown, 

 oblong to oblong-ellipsoid or spindle-shaped, 3-more-septate, the cells lenticular. 



The algal host is Trentepohlia. 



1. Sclerophyton californicum (Tuck.) Hasse, Bryologist 12:101. 1909. 



Chiodecton californicum Tuck., Syn. N. A. Lich. 2:135. 1888. 



Thallus moderately thick to thick, yellowish white and blackening, becoming 

 rough and crumbling; apothecia small to middle-sized, 0.5-1.2 mm. across, adnate, 

 round to irregular or elongated, 1-several more or less crowded on each small, 

 blackish stroma, the disk slightly concave to flat, dull black or densely whitish 

 pruinose, the exciple thick, colored like the thallus; hypothecium dark brown; 

 spores ellipsoid to oblong-ellipsoid or fusiform, 3-7-septate, 20-30 X 5-8.5 /*. 



On trees, southern California. 



63. Enterostigma Mull. Arg., Flora 68:254. 1885. 



Thallus crustose, superficial, rudimentary, devoid of differentiation into layers, 

 attached to the substratum by hyphal rhizoids; apothecia clustered in rudimentary 

 stromata, immersed to superficial, circular, the exciple rudimentary; hypothecium 

 thin, hyaline; hymenium hyaline or brownish above; paraphyses few, sparingly 

 branched; asci clavate or ovoid; spores 1-8, brown, oblong to oblong-ellipsoid or 

 ellipsoid, transversely and longitudinally septate. 



The algal host is Trentepohlia. 



1. Enterostigma Montagnaei (Tuck.) Fink n. comb. 



Chiodecton Montagnaei Tuck., Gen. Lich. 214, 215. 1872. 



Thallus granulose, widespread, greenish gray with a white cottony border; 

 stroma rudimentary; apothecia minute, 0.06-0.1 mm. across, immersed and in- 

 conspicuous when dry, round, closely clustered, the disk whitish to flesh-colored; 

 hypothecium and exciple rudimentary; asci ovoid, carrying abundant epiplasm and 

 a single spore; spores sometimes oblong, often curved and varying much in form, 

 15-23-septate transversely and 5-9-septate longitudinally, 50-60X17-24/*. 



On trees, Florida, Alabama, and Louisiana. 



17. DIRINACEAE 



Thallus crustose, showing little differentiation, attached to the substratum by 

 hyphal rhizoids; apothecia round or irregular, somewhat immersed to adnate, the 

 proper exciple surrounded by a thalloid one. 



The algal host is Trentepohlia. 



