On the Lichens near Neiv-York. 11 



bea, and possibly may be the Lecidea urceolata of 

 Acharius. 



2. nigrescens. Ach. p. 126. Common on rocks. Crust tes- 



selated, blackish ; apothecia on the areolae, black, 

 shining, scarcely distinguishable to the naked eye. 



3. margacea. Id. p. 127. Ibid. Crust ashy, rugged, and 



warty ; apothecia globose, in appearance like a Pori- 

 na with several orifices. 



13. Variolaria. 



1. velata. Id. p. 129. On bark. Crust white; disk of the 



apothecia covered with a white lamina. 



2. communis. Id. p. 130. Ibid. Crust commonly darker 



than the apothecia. 



3. amara. Id. p. 131. Ibid. Crust bitter to the taste. 



4. corallina. Id. p. 133. Encrusting decayed mosses 



Crust with coralline papillae. 



Order II. DISCOIDEI. Apothecia scutelliform, subsessile ; disk 

 different from the margin, which is formed from the frond. 



14. Urceolaria. 



1. cinerea /?. notata. Id. p. 40. On hard rocks. Crust ashy, 



smooth, and cracked; apothecia black, pruinose, im- 

 mersed in the areolae. 



2. calcarea. Id. p. 143, On calcareous rocks. Crust very 



white ; apothecia smaller than in the preceding. 



15. Lecanora. 



^ Crust adnate, uniform. 



* Apothecia with a black and naked disk. 



1. atra. Id. p. 146. On trunks and rotten wood. Crust very 



white ; apothecia crowded, angular, margin flexuous. 

 var. y. catliginosa. Ibid. Crust dark. 



2. commutata. Id. p. 149. Fences and rotten wood. Crust 



thin, with greenish white dust ; apothecia concave. 



3. pericleafi. exigua Id. p. 151. Ibid. Crust dirty white, 



and blackish; apothecia small and crowded. 



