27. Trypethelium ] 5. TRYPETHELIACEAE 61 



superficial portion convex, reddish brown to black, the ostiole minute, rarely visible, 

 the wall complete; spores ellipsoid, 3-septate, 18-23 X 8-11 /a. 

 On trees, Florida. 



3. Melanotheca aggregata (Fee) Mull. Arg., Mem. Soc. Phys. Hist. Nat. Geneve 



30:18. 1888. 



Verrucaria aggregata Fee, Essai Crypt. 91. 1824. 



Thallus very thin, smooth, dull yellowish; perithecia minute, 0.06-0.2 mm. 

 across, heaped together in a stroma or rarely solitary in stromatic elevations, the 

 superficial portion convex, black, the ostiole minute, rarely visible, the wall thin, 

 black, complete; spores oblong-ellipsoid, 3-septate, 12-18 X 5-7 /j.. 



On trees, Florida, Louisiana, and Texas. 



4. Melanotheca concatervans (Nyl.) Zahlbr., Cat. Lich. Univ. 1 :479. 1922. 

 Verrucaria concatervans Nyl., Lich. Jap. 109. 1890. 



Thallus very thin, smooth, ashy to dull yellowish; perithecia minute to small, 

 0.2-0.6 mm. across, several immersed in a stroma, or solitary in stromatic eleva- 

 tions, the superficial portion convex, black, the ostiole minute, sometimes indicated 

 by a whitish area, the wall complete; spores oblong-ellipsoid, 5-septate, 25-30 X 

 8-12 fi. 



On trees, Florida. 



27. Trypethelium Spreng., Anleit. Kenn. Gewachse 3:309. 1805. 



Thallus crustose, rudimentary, partly or wholly within the substratum, the 

 superficial portion thin, smooth to rough, devoid of differentiation into layers, or 

 showing very thin, poorly developed upper and lower cortices of entangled hyphae; 

 stroma round to irregular, hemispherical, convex or rarely fiat; perithecia minute 

 to small, several to many immersed in each stroma or rarely solitary in stromatic 

 elevations, the wall complete, the superficial portion convex to depressed, the ostiole 

 minute, often scarcely visible; hypothecium hyaline to brown; hymenium hyaline; 

 paraphyses branched and netlike interwoven; asci cylindrico-clavate ; spores 8, 

 hyaline, oblong-ellipsoid to ellipsoid or fusiform, 3-several-septate, the cells len- 

 ticular. 



The algal host is Trentepohlia. 



A. Spores not more than 3-septate 



B. Thallus yellowish to orange 1. T. aeneurn 



B. Thallus yellowish or greenish gray to ashy 

 C. Stromata blackish brown 



D. Thallus usually disappearing, indicated by 



yellowish or ashy coloration 2. T. mastoideum 



D. Thallus thin, greenish gray to yellowish 3. T. tropicum 



C. Stromata ashy to yellowish 



D. Spores 2Q-28 /x. in length 8. T. pallescens 



D. Spores 14-22 /j. in length 5. T. catervarium 



A. Spores more than 3-septate 



B. Spores not more than 9-septate 



C. Thallus ashy to brownish gray 6. T. scorites 



C. Thallus greenish yellow to brown 



D. Thallus indicated by a greenish brown coloration 7. T. exocanthum 



D. Thallus very thin, greenish yellow to brown 4. T. virens 



B. Spores 9-13-septate 9. T. eluteriae 



1. Trypethelium aeneum (Eschw.) Zahlbr., in E. & P., Nat. Pfl. 1:70. 1907. 



Verrucaria aenea Eschw., in Mart., Icon. PI. Crypt. 2:15. pi. 8, f. 3. 1828-34. 

 T. Kunzei Fee. Verrucaria heterochroa Mont. 



Thallus very thin, smooth to slightly rough, yellowish to deep orange; perithecia 

 minute, 0.08-0.15 mm. across, several to many immersed in irregular, yellowish 

 orange stromata, or solitary in stromatic elevations, the superficial portion convex, 

 black; spores oblong-ellipsoid, 3-septate, 19-27 X 7-9 /a. 



On trees, Florida. 



