264 PYEENOCARPEI [COKISCIDM 



VERRUCARIACE^.— Thallus variously crustaceous, not 

 corticated. Algal cells (gonidia) Pleurococcus or Palmella. 

 Perithecia simple with an apical ostiole. 



PYRENULACE^. — Thallus variously crustaceous, not 

 corticated. Algal cells (gonidia) Trentepohlia. Perithecia 

 simple with an apical ostiole. 



THELOCARPACE^.— Horizontal thallus wanting. Algal 

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

 gonidial sheath. 



TRYPETHELEAOE^. — 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 Trentepohlia. 

 Perithecia united under a common peridium with imperfectly 

 developed perithecial walls. 



PYRENIDIACE^. 



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 already described 

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



Thallus squamulose ; perithecia wanting 98. Coriscium. 



(Thallus shrubby ; perithecia scattered 19. Pyrenidium.) 



Thallus crustaceous ; perithecia congregate in a, 



pseudostroraa 99. Lopliotheliuih. 



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 rhizinse. — Endocarpon viride Ach. Lich. 



