72 



THE AMERICAN MONTHLY 



[Mar., 



E 



Spores polar bi-locnlar. 



1 Apothecia scutellaefortn, thallus yellowish foliaceous, the disk 



yellowish orange. 9 Theloschistes 



1 Apothecia zeorine or biatorine, thallus fruticulose, uniform and 



often yellowish 30 Placodium 



F 



Spores fusiform. 



Spores brown a 



a Apothecia orbicular, innate 



a Apo. lirellaelbrm 



a Apo. rounded or oblong 

 Spores fucescent b 



b Apo. scutellaeform 



b Apo. reniform 

 Spores colorless c 



c Th. pendulous ; 

 bloom 



c Th. granulose 



c Th. ot jointed filaments 



c Th. Iruticulose 1 



18 Solorina 



51 Opegrapha 



56 Arthonia 



15 



14 Sticta 

 Nephroma 



disk of apothecium black, with a white 



1 Roccella 



27 Ck)llema 



42 Coeogonium 



1 Apo. disk black with a white bloom 1 Roccella 



1 Apo. zeorine 31 Lecanora 



1 Thallus of jointed filaments 42 Coeogonium 



1 Apothecia patellaeform x 

 X With podecia 39 Stereocaulon 



X Without podecia 46 Lecidea 



1 Thallus caulescent 46 Lecidea 



1 Apothecia scutellaeform y 



y Thallus mostly dark green 27 Collema 



y Th. mostly lead color 28 Leptogium 



Th. frondose 2 



2 The underside with cyphels 14 Sticta 



2 Villous and veiny beneath 16 Peltigera 

 Thallus foliaceous 3 



3 Coriaceous cartilagenous, the underside with cyphels 14 Sticta 

 3 Dark green 27 Collema 



3 Lead colored z 



z Cortical layer, parenchymatous spores ovoid -ellipsoid 



28 Leptogium 

 z Cortical layer distinct, spores fusiform quadri-locular 



29 Hydrothyria 

 Thallus lobulate 4 



4 Apothecia zeorine 31 Lecanora 



4 Apo. patellaeform p 



p Apothecia stipitate 43 Baeomyces 



p Apo. sessile q 



q Exciple paler than the disk 44 Biatora 



q Exciple coal black 46 Lecidea 



Thallus obscure or almost obsolete 5 



5 Apothecia lirellseform 51 Opegrapha 

 5 Apo. rounded or oblong 56 Arthonia 

 5 Apo. innate, superficial 68 Sagedia 



Thallus uniform 6 



