210 PROCEEDINGS OF THE AMERICAN ACADEMY 



V. NEPHROxMA, Ach. 



Apothecia reniform, plane, not velate, adnale to the under side of 

 the thallus, with an elevated thalline margin. Thallus membrana- 

 ceous, softish, somewhat villous on the under side. 



Nephroma is constituted a section of Peltigera in the Lichenogra- 

 phia of Fries, but in his Flora Scanica, 1835, and his Summa Fl. Scand. 

 1845, these genera are recognized as distinct ; as they are also by Mon- 

 tagne. Fee (Crypt. Exot. Suppl. p. 8) remarks that they differ also 

 in their thecae. 



1. N. arcticum, Fr. Thallus coriaceous-membranaceous, smooth, 

 ochroleucous ; on the under side subvillous, becoming black ; fertile 

 lobules somewhat elongated, erectish ; apothecia dark orange-red. 

 Peltigera arctica, Fr. Lichenogr. p. 42. JV. polaris, Ach. Tuckerm. 

 Lich. N. E. I. c. 



Rocks among mosses, and on dwarf firs, in alpine and subalpine 

 districts. White Mountains, fertile. Abundant in Newfoundland, and 

 forming patches of two or three feet in extent, Pylaie ! in herb. 

 Kunth. Northward to Greenland, Brasen (Fl. Dan.), and elsewhere 

 in Arctic America, Rich. 



2. N. resupinatum, Ach. Th. cartilagineous-membranaceous, smooth, 

 from glaucous becoming fuscescent; pale and downy on the underside, 

 which is sparingly besprinkled with whitish soredia ; apoth. rufous-fus- 

 cous. Ach. Syn. p. 241. 



Trunks, often of mountain ash, in mountain forests, luxuriant and 

 fertile ; New England. New York, Halsey. Arctic America, Rich. 

 Darker on rocks, where it is frequently quite small. 



3. N. parile, Ach. Th. membranaceous, suborbiculate, softish, 

 livid-fuscous ; on the under side naked, rugulose, dark ; (the lacinise 

 often sorediiferous, and pulverulent at the margins), fertile lobules 

 short ; apoth. dark-fuscous. Ach. Syn. p. 242. 



Rocks. White Mountains, not uncommon. And on the coast, Mr. 

 Oakes. Fertile. 



4. N. Helveticum, Ach. Th. cartilagineous-membranaceous, some- 

 what rigid, glaucous-fuscescent ; on the under side tomentose, becoming 

 black; margins of the lobes and of the apothecia fimbriate-toothed ; 

 fertile lobules somewhat elongated ; apoth. blackish. Ach. Syn. p. 242. 



