124 



PEZIZALES 



(b) Upper surface without stiff black hairs 

 X. Epithecium with hymenial algae 

 y. Epithecium without hymenial algae 

 b. Asci 8-spored; hypothecium with algae 

 below 

 B. Thallus foliose or foliose-scaly, rarely subfruti- 

 cose; algae Scytonema, Nostoc or Palmella 



1. Apotiiecia not marginal; thallus uniform and 



typically pseudoparenchyniic throughout; al- 

 gae Scytonema 



a. Thallus of interwoven hyphae, not parenchy- 



mic 



b. Thallus pseudoparenchymic throughout 



(1) Spores 1-celled 



(2) Spores muriform 



2. Apothecia typically marginal or even with the 



thallus; thallus layered; algae Nostoc or Pal- 

 mella 



a. Thallus foliose, usually large-leaved 



(1) Apothecia on upper side of thallus 



(a) Apothecia marginal on lobes of thallus; 



lower surface of thallus netted, with- 

 out cortex 



X. Algae Nostoc 



y. Algae Palmella (Dactylococcus) 



(b) Apothecia superficial, lower surface with 



cortex below the apothecia; algae Nos- 

 toc, Palmella or both 



(2) Apothecia on lower side of elongate thal- 



lus lobes; thallus completely corticate 

 on both sides 



(a) Algae Nostoc 



(b) Algae Palmella 



b. Thallus minute of small triangular scales 



radiating from the apothecium; asci many- 

 spored; spores 2-celled 



Gonothecis 143 

 Sporopodium 143 



Arthotheliopsis 143 



Subfamily Heppiae 



Pseudoheppia 173 



Heppia 173; 29 

 Latzelia 175 



Subfamily Peltigerae 



Peltigera 189; 29 

 Peltidea 191 



Solorina 188; 29 



Nephromium 189 

 Nephroma 188 



Solorinella 188 



Family 49. LECIDEACEAE 



Zahlbruckner 131, 191, 200, 209 (114, 129, 138, 144) 



Thallus firm, not gelatinous, crustose, scaly or foliose, exceptionally dwarf 

 fruticose, with rhizoids or a navel in the larger forms, with or without cortex; 

 apothecia superficial or somewhat sunken at first, with a characteristic proper exciple 

 that is very rarely lacking, but without a true thalline exciple. The absence of the 

 latter distinguishes this family from the Parmeliaceae. 



Subfamily Lecanactidae 



A. Thallus uniform or crustose 

 1. Thallus with Trentepohlia 



a. Proper exciple thin or incomplete 



(1) Spores x-celled; paraphyses ramose, united Schismatomma 132; 30 

 (3) Spores muriform; paraphyses simple, free Melampydium 133 



b. Proper exciple well-developed, carbonous 



