76 LICHENES OF THE NORTHERN STATES 



horny within, becoming tumid, and covering the margin. Fr. ! Lichen- 

 ogr. p. 368. 



Bark of oaks, and other trees, New England. 



4. O. abnormis, Ach. Cr. thin, softish, white ; apoth. immersed, 

 very slender, short or very long, flexuous, confluent, rugose-crisped, 

 opake, black ; disk and margin somewhat confluent and indistinct. Ach. 

 Syn. p. 74. 



Hard bark of trees ; Pennsylvania, Muhl. , Ach. A mostly tropical 

 species growing on Cascarilla, and other bark. 



Sect. II. Graphis. Apothecia erumpent, coronate for the most part 

 with a thalline margin. 



5. O. scripia, Ach., Schser. Cr. innate in the matri.x, becoming at 

 length exposed, uneven, and pulverulent; apoth. immersed, erumpent, 

 with a raised accessory thalline margin ; the proper margin tenuescent, 

 smooth ; the disk linear, at first csesious-pruinose. Fr. Lichenogr. p. 

 370. Schar. ! Spicil. p. 46. — a. limitata, Schasr. ; apoth. emergent, 

 scattered irregularly, various. Fr. I. c. Schar. I. c. — (J. recta, Schter. ; 

 apoth. immersed, straight, parallel, disk somewhat dilated. Fr. I. c. 

 Schar. I. c. O. recta, Himib. 0. Cerasi 4" letuligna, Ach. — /.. ser- 

 penlina, Schser. ; apoth. immersed, flexuous, very long, the thalline 

 margin tumid, evanescent. Fr. I. c. Schcer. 1. c. 0. serpentina, Ach. 



Bark of trees ; New England. New York («, /?, and ;'), Halsey. 

 Pennsylvania (« and ;?), Muhl. 



6. O. polymorpha. Cr. somewhat pulverulent, whitish-cinerascent 

 or very white ; apoth. somewhat rounded or oblong, irregular, without 

 apparent proper margin, from plane becoming tumid and elevated- 

 punctate, angulose, repand, or somewhat stellate-ramiilose, csesious- 

 pruinose, with a more or less conspicuous thalline margin. Arlhonia 

 polymorpha, Ach. Syn. p. 7. Fee Crypt. Exot. p. 53. Eschw. Lich. 

 Bras. I. c. p. 111. O. Cascarillce, Floerk.! herb. {Jide ips.). 



North America (Pennsylvania ?), Muhl. A common Lichen of Cas- 

 carilla bark, which Eschweiler (1. c.) has illustrated at length. The 

 arrangement of Muhlenberg's catalogue leaves it probable that he con- 

 sidered it to occur within our limits. 



7. O. inusia, Ach. (sub Graph.). Cr. membranaceous, somewhat 

 rugulose, pale-virescent, decussated by black lines ; apoth. minute, im- 

 mersed, rather short, straight, simple or somewhat stellate-ramose, ob- 



