128 CUMMINGS 



167. Umbilicaria cylindrica (L.) Dub. 



Lichen cylindricus LiNNiEUS, Afz, Act. Sc. Sv. 1788. 



Umbilicaria cylindrica Duby, Bot. Gall. 595. 1829, — Dill. Hist. Muse. /. 2g. 

 f. 116. 



Unalaska (Setchell). Collected by Macoun on St. Paul and St. 

 George Islands, Bering Sea. 



A common and widely distributed northern lichen. 



Additional species of Umbilicaria : Wright collected U. Jlocculosa 

 Hoffm. at Bering Strait, Macoun collected U. rugifera Nyl. on rocks 

 on St. Paul and St. George Islands. 



Family PARMELIACEJE. 

 PHYSCIA. 



KEY TO THE SPECIES. 



Thallus brown. 



Thallus closely adnate to the substrate, lobes very thin and flat. 



adglutinata. 

 Thallus not closely adnate to the substrate, the tips rounded and 



erect .fulverulenta. 



Thallus gray. 



Thallus granulate or sorediate. 



Lobes of thallus very narrow, granulate at tips trihacea. 



Lobes of thallus rather wide, sorediate ccesia, 



Thallus neither granulate nor sorediate. 



Lobes of thallus rather broad, with white fibrils underneath. 



stellaris. 

 Lobes of thallus narrow, with black fibrils beneath. 



stellaris apiola. 



168. Physcia adglutinata (Floerk.) Nyl. 



Lecanora adglutinata Floerke in Deutsch. Lich. Lief. 4: 7. 18 15. 

 Physcia adglutinata Nylander, Syn. 428. i860. 

 Lichen elanius Sowerby, Eng. Bot. t. 21^8. 



Muir Glacier (Trelease, 1154^). New to Alaska. On Salix with 

 Parmelia olivacea. Specimen fertile. 



Not recorded as occurring in Greenland, Newfoundland, or Lab- 

 rador, but widely distributed to the west and south. 



169. Physcia caesia (Hoffm.) Nyl. 



Lichen ccEsius Hoffmann, Enum. /. 12. f. i. 1784. 



Physcia ccEsia'^Y-LA.^n^K, Syn. 426. i860. — Sowerby, Eng. Bot. /. ioj2. 



Yakutat (Trelease, 11393); Farragut Bay (Trelease, 1141); 

 Kukak Bay, Alaska Peninsula (Coville and Kearney, 1515c in part) ; 



