8o PARMELIACEAE 



(b) Spores 2-celled ; paraphyses branched and united 



Varicellaria 198 

 I). Asci many-spored ; spores i-celled, more rarely 2-celled 



Subfamily Acarosporae 150 



(1) Apothecia superficial 



(a) Thallus bright yellow *Pleochroma 207 



(b) Thallus not bright yellow Maronea 152 



(2) Apothecia typically immersed, with mostly narrow disk 



Acarospora 152 

 2. Algae Chroolepus or Phyllactidium ; apothecia with thalline exciple, at least 

 when young Subfamily Gyalectae 124 



(inch Thelotremae 118) 



a. Thalline exciple present and persistent 



(1) Spores i-celled Jonaspis 125 



(2) Spores 2-celled *Ocellis 118 



(3) Spores 4-many-celled 



(a) Spores clear 



x. Apothecia sprouting repeatedly from the margin, forming erect forked 



chains of apothecia Polystroma 121 



y. Apothecia not in chains 

 (x) Algae Chroolepus 

 m. Exciple and hypothecium clear 



Ocellularia 118 

 n. Exciple and hypothecium dark, hard 



Sagiolechia 126 

 (y) Algae Phyllactidium Phyllophthalmaria 120 



(b) Spores brown Phaeotrema 119 



(4) Spores muriform 



(a) Spores clear 



x. Paraphyses simple, free Thelotrema 119 



y. Paraphyses branched and united 



*Phanotylium 121 



(b) Spores dark or brown 



x. Paraphyses simple, free Leptotrema 120 



y. Paraphyses branched and united 



(x) Apothecia sunken in groups in a stroma 



Tremotylium 120 

 (y) Apothecia not in a stroma 



Gyrostomum 120 



b. Thalline exciple present at first, then more or less completely disappearing 



(1) Asci 1-8-spored 



(a) Spores 2-celled Microphiale 125 



(b) Spores 4-many-celled Bryophagus 126 



(c) Spores muriform Gyalecta 125 



(2) Asci 12-many-spored 



(a) Spores 2-celled Ramonia 125 



(b) Spores 6-many-celled Pachyphiale 126 



II. Thallus typically foliose or fruticose, sometimes small-leaved or scaly; thalline 

 exciple sometimes lacking 



