OF ARTS AND SCIENCES. 223 



very numerous apothecia. Lecanora caudelaris, /5. Ach. — ^. lohulata, 

 Fr. ; th. obliterated, or consisting only of very short, scattered, ap- 

 pressed lobules, with small apothecia. — tj. suistellata, Ach. ; th. folia- 

 ceous, substellate, lacerate-laciniate, lacinitB expanded, pulverulent. — 

 &. concolor, Fr. ; th. pulverulent, squamulose, lacerate-laciniate, scales 

 crowded, ascendant. Lecan. caudelaris, a. Ach. — i. citrinella, Fr. ; 

 the whole thallus dissolved into a yellowish-green dust. 



Very common : a, on trunks, rocks, &c. ; (5, on rocks and stones 

 (especially maritime), exposed to the sun; y and 5, on trunks, exposed 

 to the sun ; t and ^, on the smaller branches and twigs of trees ; r] and 

 &, on smooth bark, the last also common on dead wood ; /, on bark and 

 dead wood in moist places ; New England. New York {y and ■&), Hal- 

 sey. Pennsylvania {&)., Muhl. Ohio («), Mr. Lea ! Illinois («), Rus- 

 sell! Northward to Nova Scotia (;'), Menzies ! Newfoundland («), 

 Pylaie, and Arctic America {s and •&), Rich.! I have adopted 

 Fries's view of the European species nearly entire. He remarks that 

 he has distinguished and enumerated these forms, not so much on ac- 

 count of their importance as distinct states, as to furnish an example, 

 that can almost everywhere be authenticated, of the extremely Protean 

 character of the thallus of Lichens. 



23. P. diversicolor, Ach. Th. suborbicular, yellowish-orange-red 

 (becoming whitish with age), of rather narrow, somewhat lacerate-ra- 

 mose, rugose, at length concrete lacinise ; white-cinerascent, with fibres 

 of the same color beneath ; apoth. numerous, concave, blackish-san- 

 guineous, margin thick, at length white. Ach. Syn. p. 210. 



Arctic America, and southward, Ach. 



24. P. chrysophthalma, Ach. Th. subfoliaceous, cartilagineous- 

 membranaceous, lacerate-ramose, from dark reddish-yellow becoming 

 whitish ; on the under side whitish, and fibrillose at the margins ; la- 

 cinia: depressed-subascendant, plano-convex, pinnatifid ; apoth. dark- 

 orange, fibrillose-ciliate or naked. Fr. Lichenogr. p. 75. Borrera, 

 Ach. — ,5. exilis, Fr. ; lacinise very narrow; margins of the apothecia 

 naked. Fr. I. c. Borrera, Ach. 



Trunks and branches of trees near the coast, and luxuriant in places 

 exposed to the sea-spray ; New England. New York, Torrey (at New- 

 burgh, Russell !). Pennsylvania, Muhl. Illinois, Russell ! 



