Tribe VI. CLADONIEI Xyl. Thallus foliaceous or fruticiilose, 

 with fistulosc podetia : apothecia terminal on the podetia, rarely 

 sessile on the basal thaUus, biatorine. 



31. Pycnothelia Duf. Thallus granuloso-crustaceous, podetia 

 clavate, papiUseform, glabrous : apothecia brown, with simple spores; 

 spermogones with simplish sterigmata and curved spermatia. 



32. Cladonia Hill. ThaUus foliolose or squamulose; podetia 

 branched or seyphose, pulverulent and squamose : apothecia browu 

 or scarlet, with simple spores ; spermogones with simplish sterig- 

 mata and cylindrical straight or somewhat cuiwed spermatia. 



33. Cladina Xyl. ThaUus leafless ; podetia ascyphous, branched, 

 smoothish : apothecia brown, with simple spores ; spermogones with 

 simpUsh sterigmata and straight or usuaUy curved spermatia. 



Series III. BAMALODEI l^j\. ThaUus efoUolose, fruticulose 

 or filamentose : apothecia generaUy lecanorine or parmelioid. 



Tribe VII. EOCCELLEI Xyl. Thallus simplish or branched, 

 intemaUy with filamentose medulla : apothecia often irregular, 

 adnate, terminal or lateral. 



34. Roccella DC. ThaUus fruticulose from a common base : 

 apothecia normally lecanorine, blackish, with 3-septate spores ; 

 spermogones with simplish sterigmata and arcuate spermatia. 



Tribe VIII. SIPHULEI Xyl. ThaUus podetiiform, simple or 

 fruticulose, internaUy with filamentose or fistulose meduUa ; apo- 

 thecia not rightly known. 



35. Thanmolia Ach. ThaUus subulato-stipitate, internaUy fistu- 

 lose: apothecia unknown ; spermogones with jointed sterigmata and 

 cylindrical, slightly apicaUy incrassate spermatia. 



Tribe IX. RAMALINEI Xyl. ThaUus fruticuloso-foUaceous, 

 rounded or compressed, with wooUy medulla : apothecia lecanorine, 

 scuteUate. 



36. Ramalina Ach. ThaUus ramoso-laciniate, meduUa arach- 

 noid : apothecia terminal or lateral, subconcolorous, with 1-septate 

 spores ; spermogones with pauci-articulate sterigmata and straight 

 cylindrical or oblongo-cyUndrical spermatia. 



Tribe X. USNEEI Xyl. ThaUus very much branched, rounded 

 or compressed, with firm medullary axis : apothecia parmelioid, 



peltate. 



