17. Polyblastiopsis ] 4. PYRENULACEAE 51 



B. Spores commonly more than 25 fi in length 



C. Thallus thin, smooth to chinky or powdery, ashy to grayish 

 D. Thallus sometimes becoming powdery ; spores 



30-38 X 15-16 fi 5. P.dealbens 



D. Thallus becoming chinky and subareolate; spores 



20-34 X 8-14 n 4. P. lactea 



C. Thallus rather thick, chinky-areolate, dull brownish . . . 3. P. inductula 

 A. Spores more than 50 /x in length 



B. Spores large, 50-68 X 13-16 /i !• P. floridana 



B. Spores larger, 118-160 X 28-10 n 2. P.intrusa 



1. Polyblastiopsis floridana Fink; Hedrick, Mycologia 25:307. 1933. 



Thallus thin to moderately thick, becoming rough and warty, yellowish ashy, 

 varying toward brownish; perithecia minute to small, 0.1 5-0.4 mm. across, im- 

 bedded in thalloid warts, the wall dimidiate, the apex visible and black, with the 

 ostiole sometimes showing; asci long-clavate; spores 4- rarely 6 or 8, ellipsoid, 

 7-9-septate transversely and 1-2-septate longitudinally, 50-68 X 13-16 fi, irregu- 

 larly arranged. 



On trees, Florida. 



2. Polyblastiopsis intrusa (Nyl.) Zahlbr., Cat. Lich. Univ. 1:349. 1922. 



Verrucariaintrusa Nyl., Mem. Soc. Acad. Maine et Loire 4:43. 1858. 



Thallus very thin, smooth to slightly rough, ashy to grayish brown, or im- 

 bedded and indicated by a grayish area; apothecia minute to small, 0.1-0.25 mm. 

 across, immersed, the ostiole minute, rarely visible, the wall dimidiate; spores 1 

 or rarely 2, brownish to brown, oblong, 2 3-31 -septate transversely and 6-9-septate 

 longitudinally, 118-160 X 28-40 /x. 



On trees, North Carolina, South Carolina, and Florida. 



3. Polyblastiopsis inductula (Nyl.) Fink n. comb. 



Verrucaria inductula Nyl., in Hasse, Bull. Torr. Club 24:448. 1897. Polyblastia 

 (?) inductula (Nyl.) Zahlbr. 



Superficial thallus rather thick, widespread, chinky-areolate, dull brownish; 

 perithecia small to middle-sized, 0.2-0.5 mm. across, largely immersed in the 

 thallus except dark at the apex, the ostiole minute; spores 6-10-septate trans- 

 versely and 1-2-septate longitudinally, 26-32 X 10-14 fi, uniseriately to irregularly 

 arranged. 



On shale, Santa Monica Range, California. Omitted by Hasse in his Lichens 

 of Southern California, but recognized by Zahlbruckner in Catalogus Lichenum 

 Universalis as a distinct species. 



4. Polyblastiopsis lactea (Mass.) Zahlbr., in E. & P., Nat. Pfl. 1 1 :65. 1907. 



Blast odesmia lactea Mass., Ric. Lich. 181. f. 369. 1852. Pyrenula lactea (Mass.) 

 Tuck. 



Thallus very thin to thin, smooth to slightly rough, ashy gray to whitish, 

 becoming chinky and subareolate; perithecia minute, 0.1-0.25 mm. across, round, 

 the superficial portion strongly convex and black, the ostiole minute and scarcely 

 visible; spores 4-8, hyaline or tinged brownish, oblong-ellipsoid, 5-7- or rarely 9- 

 septate transversely and 1-3- or rarely 5-septate longitudinally, 20-34 X 8-14 /j., 

 irregularly arranged. 



On trees, New England to South Carolina, and westward to Tennessee, and in 

 Illinois. 



5. Polyblastiopsis dealbens Fink; Hedrick, Mycologia 25:307. 1933. 



Thallus thin and ashy, smooth to slightly rough, chinky, sometimes becoming 

 powdery; perithecia minute to small, 0.15-0.4 mm. across, round to irregular, the 

 superficial portion depressed-convex, black or more commonly whitish pruinose. 

 the ostiole rarely visible; hypothecium dark brown; spores 4-8, oblong-ellipsoid, 

 8-9-septate transversely and 1-2-septate longitudinally, 30-38 X 15-16 fx, irreg- 

 ularly arranged. 



On trees, South Carolina and Tennessee. 



