OF ARTS AND SCIENCES. 237 



the extreme development of Lichenes, and Cladonia, or some other ge- 

 nus expressing the horizontal type, as representing their typical perfec- 

 tion. — S. ramulosmn, Ach., a mostly tropical species, with densely 

 fibrillose podetia, and terminal, subglobose apothecia, inhabits North 

 America, according to Acharius and Muhlenberg ; but it is probable, 

 only the southern part. 



Sect. I. Podetia solid, filamentous within ; apothecia normally fus- 

 cous. 



* Squamules foliaceous, or fibrillose. 



1. S. tomentosum, Fr, Podetia lax, terete, very much branched and 

 the branches somewhat recurved, clothed with a dense, whitish, spongy 

 tomentum ; squamules somewhat rounded, incised-crenate (becoming 

 phylloid-granulose), cinereous-caesious ; apothecia minute, lateral, at 

 length globose. Fr. Lichenogr. p. 201. 



On the earth and stones in the lower regions of the White Moun- 

 tains, and ascending; fertile. Northward to Arctic America, Herb. 

 Hook. ! 



2. S. corallinum, Fr. Podetia lax, a little compressed, very much 

 branched, glabrous (many conjoined at the base into a dense, at first 

 digitate-divergent sod) ; squamules fibrillose, somewhat digitate-ramose, 

 cinereous-csesious ; apoth. scattered or conglomerate (rather large), 

 finally globose. Fr. Lichenogr. p. 201. S. dactylophyUmn, Floerk. ! 



Stones, in the lower regions of the White Mountains ; fertile. 



3. S. paschale, Laur. Podetia lax, rather slender, somewhat com- 

 pressed, very much branched, subglabrous (many commonly crowded 

 thickly together, but not caespitose-conjoined) ; squamules phylloid- 

 granulose, crenate, conglomerate, glaucous ; apoth. subterminal, di- 

 lated, plane. Fr. Lichenogr. p. 202. S. paschale, Ach. part. Lichen 

 paschalis, L. Jide Fr. 



Stones, and on the earth in large patches, in the lower regions of the 

 White Mountains ; and ascending to alpine districts. Common also on 

 the coast ; but the genus is peculiarly montane. The present species 

 was formerly considered as including most of those here described, 

 and the following stations are therefore so far uncertain. New York, 

 Torrey. Pennsylvania, ilf«/tZ. Northward to Canada, ilfic/icri^x; New- 

 foundland, Pi/ Zaie ; the Saskatchawan, &c.. Rich.; Greenland, Gie- 

 seke, ; and Melville Island, R. Br. 



