32 



LICHENES OF THE NORTHERN STATES 



Subsect. II. Physcia, Fr. 



25. P. ciliaris, Ach. Thallus cartilagineous, from green becoming 

 glaucous ; laciniffi linear, ramose, subascendant, channelled beneath, 

 ciliate with simple fibres ; apothecia subterminal, pedicellate, margin 

 erect, at length lacerate-dentate, fimbriate, or obliterated in foliaceous 

 branches ; disk plane, black, subpruinose. Fr. Lichenogr. p. 77. Bor- 

 rera, Ach. — /5. galactophyUa,TuckeTm.; more delicate ; the lacinise 

 very white and powdery beneath ; margins of the apothecia at length 

 obliterated in foliaceous expansions ; disk white-pruinose. P. galaclo- 

 phylla, Willd. herb. J — y. angustata, Tuckerm. ; lacinias extremely 

 narrow, of nearly the same color beneath, subterete at the apices. 

 Borrera angustata, Bory ins. 



Trees, New England (8), rare. New York, Torrey. Pennsylva- 

 nia (/?), Muhl. ! and southward, where /? is common. North to Arctic 

 America, Rich. — /, Newfoundland, Bory in herb. Berol. ! Rocky 

 Mountains, Herh. Hook. ! P. leucomela, Ach., a species near this, but 

 with narrow, ascendant lacinias, and tomentose marginal fibres, occurs 

 in the Carolinas, Michx. / and California, Menzies! and P. erinacea, 

 Fr., with lacerate-laciniafe, diffuse lobes, which are ciliate, and beset 

 above with very long whitish fibres, in California, Menzies ! 



26. P. detonsa, Fr. Th. cartilagineous, substellate, naked, glaucous- 

 fuscescent (and fuscous) ; /whitish on the under side with black fibres; 

 lacinisD narrow, linear, somewhat convex, digitate-multifid, often semi- 

 terete, very densely crowded together and imbricated ; apoth. subses- 

 sile, margin at length crenate, and leafy, disk plane, becoming dark- 

 fuscous. Fr. Syst. Orb. Veg. fide ipsius. P. Novce Anglia, Tuckerm. 

 in lilt. olim. P. aquila, Muhl. Catal. 



Rocks and trees. New England. Ohio, Mr. Lea ! Near to P. aqui- 

 la. I have not seen Fries's description. 



27. P. pulverulenia, Fr. Th. cartilagineous, substellate, pruinose- 

 cinereous ; black on the under side and hispid-tomentose ; lacinise lin- 

 ear, multifid, approximate ; apoth. sessile, margin tumid, entire, or 

 squamulose-foliose, disk plane, black-fuscous, subpruinose. Fr. Lich- 

 enogr. p. 79. P. pulverulenia, venusta, 4" muscigena, Ach. — ^. leu- 

 coleiples, Tuckerm. ; the whole thallus white-farinose-pruinose, lobes 

 radiant, margins interruptedly inflexed and pulverulent ; apoth. sub- 

 sessile, disk depressed, white-pruinose, margin subduplicate, the ex- 

 ternal border foliose or entire. Lichen leucoleiptes, Muhl. in herh. 



