GENERAL KEY TO FAMILIES 



25 



t. Hyphae constricted or dcmatioid, 

 or in slimy skeins wlien 

 straight-walled; perithecia of 

 rounded cells or agglutinate 

 straight-walled meridian hyphae 

 (n) Perithecia radiate; asci hanging 

 from the apparent tip 

 (y) Aerial mycelium lacking; perithecia 

 borne on an innate-erumpent 

 stroma, elongate 

 (b) Ostiole regularly present 

 X. Perithecial wall distinct; perithecia sepa- 

 rate or in a stroma 

 (x) Perithecia net parasitic on algae, 



without a thallus 

 m. Perithecia dark, membranous to car- 

 bonous 

 (m) Ostiole papillate or conical, 



round, not compressed 

 (n) Ostiole broad and compressed, 

 the opening linear 

 n. Perithecia bright-colored, rarely 

 whitish, fleshy 

 (y) Perithecia parasitic on algae, typi- 

 cally with a thallus 

 (z) Asco! .ata at first perithecioid, then 

 cupaloid, in a ramose or alveolate 

 stroma 

 y. Perithecial wall indefinite or lacking; 

 perithecia reduced to locules in a 

 stroma 

 (x) Perithecia not parasitic on algae, 



without a thallus 

 m. Locules distinct, perithecium-like, 

 typically ostiolate, with many asci 

 and usually with paraphyses 

 n. Locules mere hollows filled by single 

 asci and separated by stromal tis- 

 sue or rarely by paraphysoids 

 (y) Perithecia parasitic on algae, typi- 

 cally with a thallus 

 b. Asci borne in hysterothecia or dimidiate as- 

 comata 



(1) Asci borne in hysterothecia, the ostiole 



cleftlike or sometimes stellate 



(a) Not parasitic on algae, thallus lacking 



(b) Parasitic on algae, thallus present 



(2) Asci borne in dimidiate ascomata with a 



scutellum radiate in whole or in part 

 as a rule 

 (a) Scutellum radiate 

 x. Apothecia or hypostroma innate or 



erumpent 

 y. Apothecia superficial, hypostroma none 



Capnodiaceae p. 56 

 Trichothyriaceae p. 58 



Coryneliaceae p. 58 

 Sphaeriales p. 58 



Sphaeriaceae p. 59 

 Lophiostomaceae p. 82 

 Hypocreaceae p. 76 

 Verrucariaceae 84 



Cyttariaceae p. 83 



Dothideales p. 88 



Dothideaceae p. 89 



Myriangiaceae p. 92 

 Mycoporaceae p. 94 



Hysteriaceae p. 102 

 Graphidaceae p. 104 



Polystomellaceae p. 95 

 Microthyriaceae p. 98 



