LICHENS 
99 
Two additional species have been credited to Alaska : S. coralloides 
Fr., collected on St. Paul Island by William Palmer, determined by 
W. W. Calkins, and S. wrightii Tuck., collected by Wright on the 
islands of Bering Strait. 
Family LECANORIACE^. 
PERTUSARIA. 
KEY TO THE SPECIES. 
Plants growing on the earth, incrusting mosses, etc. 
Lobes of the thallus finger-shaped, apothecia solitary. dactylina. 
Lobes of the thallus flat, apothecia crowded. .glotnerata. 
Plants growing on bark or on rocks. 
Apothecia underneath the bark, becoming emergent. ..carneopallida. 
Apothecia external. 
Apothecia compound, difform. 
Apothecia and spores medium to large size. ..co??imunis. 
Apothecia and spores small.. ...pustulata. 
Apothecia not compound. 
Thallus thin, not sorediate, apothecia soon powdery. 
multipuncta. 
Thallus irregularly thickened, often sorediate, apothecia not 
powdery..... .pocillaria. 
82. Pertusaria glomerata (Ach.) Schaer. 
Porina glomerata Acharius, L. U. 31 o. t. J. f. 2. 181 o. 
Pertusaria glomerata Schaerer, Spicil. 66. 1823. 
Hall Island (Trelease, 863) ; Port Clarence (Trelease, 864). 
The specimens which grow over mosses are well fruited. A 
specimen which Rothrock lists was collected at Port Mulgrave. 
Wright collected it on the islands of Bering Strait, while Nylander 
records it for Konyam Bay and Bering Island, on the Asiatic side of 
the Strait, and Dr. Bean collected it at Port Mulgrave. It has been 
collected on the White Mountains, but I find no record for Labrador, 
Newfoundland, or Greenland. 
83. Pertusaria pustulata (Ach.) Nyl. 
Porina pustulata Acharius, L. U. 309. 1810. 
Pertusaria pustulata Nylander, Prodr. Gall. 195. 1857. 
Yakutat Bay (Trelease, 819); Farragut Bay (Trelease, 523). 
New to Alaska. 
The most northern station recorded in North America is Oregon, 
