264 PYKENOCARPEI [OORISCIOM 



VEllRUCARrACE^.- Thallus variously crustaceous, not 

 corticated. Algal cells (gonidia) Pleurococcus ov Palmella. 

 Perithecia simple with an apical ostiole. 



PYRENULACEiE. — Tliallus variously crustaceous, not 

 corticated. Algal cells ((jonidia) Trentepoldia. Perithecia 

 simple with an apical ostiole. 



THELOCARPACE^.— Horizontal thallus wanting. Algal 

 cells {gonidia) Pleurococcus. Perithecia simple, surrounded by a 

 gonidial sheath. 



TRYPETHELE ACE^.— Thallus crustaceous or almost 

 obsolete, not corticated. Algal cells {gonidia) Trentepohlia. 

 Perithecia united in a common stroma. 



MYCOPORACE^.— Thallus crustaceous or almost obsolete, 

 not corticated. Algal cells {gonidia) Palmella or TrentejpoJdia. 

 Perithecia united under a common peridium with imperfectly 

 developed perithecial walls. 



PYRENIDIACEJE. 



Thallus squamulose, minutely shrubby or crustaceous. Algal 

 cells {gonimia) Cyanophycese. Perithecia simple, innate or super- 

 ficial ; spores 4-8 in the ascus, simple or septate, colourless or 

 coloured. 



The Order includes the genus Pyrenidium, alreadj' described 

 (Part I. p. 81), and three other genera : — 



Thallus squamulose ; perithecia wanting 98. Coriseium. 



(Thallus shrubby ; perithecia scattered 19. Pyrenidium.) 



Thallus crustaceous ; perithecia congregate in a 



pseudostroma 99. Lopliotheliuni. 



Thallus wanting ; perithecia parasitic 100. Obryzum. 



98. CORISCIUM Wainio Lich. Bresil ii. p. 188 (1890). 

 (PI. 35.) 



Thallus squamulose, upper surface corticated, lower surface 

 of loose straggling hyphse. Algal cells Microcystis {Polycoccus 

 Kiitz.) occurring in compact, closely crowded groups, which are 

 surrounded and penetrated by the fungal hyphse. Perithecia 

 and spermogones unknown. 



Distinguished by the nature of the algal cells {gonimia). 



1. C. viride A. Zahlbr. in Engler & Prantl Pflanzenf. i. 1*, 

 p. 77 (1903). — Thallus bright bluish-green, squamulose or lobed 

 and sinuate, somewhat imbricate, closely adhering to the sub- 

 stratum, but rather concave with the margins raised, under 

 surface white, without rhizinae. — Endocarjpon viride Ach. Lich. 



