OF ARTS AND SCIENCES. 395 



11. P. STELLARI3 (L.) : tliallo subcartilagineo glaucescente epruinoso 

 subtus glabro e pallido nigricante fibrilloso ; laciniis multifidis ; apothe- 

 ciis sessilibus, mai'gine tumidulo subintegro, disco fusco-atro subpruinoso. 

 Fr. Lichenogr. p. 82, panels mutatis. Spora3 octonai', ellipsoideaj, fus- 

 cescentes, uniseptatas. 



Vax'. a. AiPOLiA, Schser. : stellata, nuda, glabra ; laciniis convexiusculis 

 subtus pallidis. Lichen stellaris, L. pro parte. Parmelia, Ach. ; Fr. 

 Lichenogr. 1. c, a; Moug. & Nestl. Cr. Vog. n. 163; Schaar. Spicil. 

 p. 438, & Lich. Helv. n. 350, 351 ; Tuckerm. Synops. Licb. N. E. 

 p. 33, & Lich. exs. n. 83 ; Nyl. Prodr. Gall. p. Gl. On trees, dead 

 wood, and rocks. Pennsylvania, Muhlenberg. New York, Torrey. 

 Arctic America, Richardson. New England, exceedingly common, 

 in forms with the lobes subconnate (P. aijiolia, Ach.), and more dis- 

 tinct {P. aipolia, v. a7ithelina, Ach.), and a slender rock -form diverging 

 yet farther (P. phcea, Tuckerm. in Darlingt. Fl. Cestr. p. 440) and 

 continuing common southward to Virginia. North Carolina, Rev. Dr. 

 Curtis. South Carolina, Mr. Ravenel. Alabama, Mr. Peters. Louis- 

 iana, Dr. Hale. Texas, Mr. Wright. New Mexico, 3£r. Fendler. All 

 the specimens from Carolina southward shoAV a tendency to pass into 

 smaller, narrower states, which appear to be inseparable, specifically, 

 from the next. 



Var. /3. ASTROIDEA : stellata, nuda, glabra, microphylla ; laciniis planis 

 mox sorediatis subtus e pallido demum nigris. P. astroidea, Clem. 

 Ens. Add. p. 302, cit. Ach. ; Fr. Lichenogr. p. 81 ; Tuckerm. Enum. 

 Lich. N. Amer. p. 50 ; Nyl. Prodr. Gall. p. 62. P. Caricce, Clem. 

 1. c. Lecanora, Ach. Syn. p. 188. P. Clementiana, Ach. Lichenogr. 

 p. 483 ; Syn. p. 201 ; Moug. & Nestl. Cr. Vog. n. 737. P. Clementi, 

 Turn, in Linn. Trans. IX. p. 140, tab. 13, fig. 1. P. sidei-alis, Ach. 

 Syn. p. 207. P. ohsessa, Ach. Syn. p. 213; Montag. Cuba, p. 227. 

 P. astroidea, var. ohsessa, Nyl. Lich. Exot. 1. c. p. 255. On trees. New 

 England to Virginia, becoming more common southward. Pennsyl- 

 vania (Partn. ohsessa), Muhlenberg. North Carolina, Rev. Dr. Curtis. 

 South Carolina, Mr. Ravenel. Alabama, Mr. Peters. Louisiana, Dr. 

 Hale. Texas, Mr. Wright ; who has also collected the same plant in 

 the Loo Choo Islands (U. S. N. Pacif. Expl. Exp.) and in Japan ; the 

 latter only differing from the type in its rounded soredia ; also in Cuba 

 and Nicaragua. The North American Lichen referred here occurs in 

 forms which I cannot distinguish from normal Portuguese specimens 



