52 4. PYRENULACEAE [ 18. Pseudopyrenula 



6. Polyblastiopsis fallaciosa (Stizenb.) Zahlbr., in E. & P., Nat. Pfl. 1 1 :6S. 1907. 



Sporodictyon fallaciosum Stizenb.; Am., Flora 46:604. 1863. Pyrenula falla- 

 ciosa (Stizenb.) Willey. 



Thallus thin, ashy gray, slightly rough, or the superficial portion sometimes 

 absent and the imbedded portion indicated by a grayish coloration; perithecia 

 minute, 0.15-0.25 mm. across, the superficial portion hemispherical, black, the os- 

 tiole minute, rarely visible, sometimes indicated by a whitish area, the wall 

 dimidiate; hypothecium hyaline; spores 8, ellipsoid, 5-7-septate transversely and 

 1-2 -septate longitudinally, 14-21 X 6-8 /x, irregularly arranged. 



On trees, New Hampshire, Massachusetts, and Illinois. 



7. Polyblastiopsis fallax (Nyl.) Fink n. comb. 



Verrucaria epidermidis var. fallax Nyl., Bot. Not. 178. pi. 1, f. 126. 1852. Artho- 

 pyrenia punctiformis var. fallax (Nyl.) Anzi. Pyrenula punctiformis var 

 fallax (Nyl.) Willey. Didymella fallax (Nyl.) Vainio. Arthopyrenia fallax 

 (Nyl.) Arn. 

 Thallus very thin or more commonly imbedded and indicated by greenish-gray 

 to ashy coloration of the substratum; perithecia minute to small, 0.1-0.5 mm. 

 across, round to oblong, the superficial portion depressed-convex, black, the wall 

 dimidiate, the ostiole minute and not often visible; spores 8, oblong-ellipsoid, 

 3-5-septate transversely and becoming 1 -septate longitudinally, 16-24 X 5-8 /x, 

 irregularly arranged. 



On trees, Massachusetts, New York, Missouri, Iowa, and Minnesota. 



OTHER SPECIES REPORTED 

 Polyblastiopsis dispora (Mull. Arg.) Zahlbr.— Texas. 



18. Pseudopyrenula Mull. Arg., Flora 66:247, 248. 1883. 



Thallus forming a thin, smooth crust over the substratum, partly or wholly 

 within the substratum, devoid of differentiation into layers; perithecia small to 

 middle-sized, more or less immersed, often surrounded by a thin, thalloid veil, 

 the superficial portion a flat, black apex, the ostiole minute, the wall dimidiate or 

 complete; paraphyses branched and netlike interwoven; asci clavate to cylindrico- 

 clavate; spores 8, hyaline, oblong to oblong-ellipsoid, 3-septate (rarely more), 

 the cells lenticular or almost spherical. 



The algal host is Trentepohlia. 



1. Pseudopyrenula Pupula (Ach.) Mull. Arg., Flora 68:331, 332. 1885. 



Pyrenula Pupula Ach., Meth. Lich. 123. 1814. Pyrenula discolor Fee. 



Thallus thin, rudimentary, the superficial portion sometimes absent and the 

 imbedded portion indicated by a smooth, olive-green to yellowish or whitish area; 

 perithecia small to middle-sized, 0.4-0.8 mm. across, the wall thin, complete, im- 

 bedded in conical elevations, the flat, black apex showing, surrounded by a whitish 

 area of the thalloid covering, and sometimes showing the minute ostiole at the 

 tenter; spores 3-septate, oblong-ellipsoid, 28-36 X 10-13 p, biseriately to irregularly 

 arranged. 



On trees, Florida. 



19. Porina Mull. Arg., Flora 6t>:320. 1883. 



Thallus forming a very thin to thin, smooth to minutely rough crust over the 

 substratum, partly or wholly within the substratum, devoid of differentiation into 

 layers; perithecia minute to small, more or less immersed, the superficial portion 

 hemispherical or somewhat convex, the ostiole minute, punctiform, the wall di- 

 midiate or rarely complete; paraphyses unbranched, rarely forked at the apices; 

 asci clavate or cylindrico-clavate ; spores commonly 8, hyaline, ellipsoid, fusiform 

 or acicular, 3- rarely 1-7- or more-septate, the cells cylindrical. 



The algal host is Trentepohlia. 



