R. LINDSAY ON THE LICHEN-FLORA OF GREENLAND. 291 



Iceland * nearly as far as south as lat. 64°. U. Pennsylvanica 

 occurs in the United States as far south, at least, as lat. 40°. L. 

 Tornceensis descends below the Arctic Circle, but apparently not 

 many miles. L. subfuscula appears to be what Nylander named 

 in my Herbarium L. hacillifera, var. subfuscula. It occurs in 

 Iceland.l L. cororiata {Rhexopliialc of Th. Fries, Arct., p. 705) 

 appears to be the Lecidea rhexoblephara, Nyl. (Scand., 240, 

 and Carroll, 290). If so, it occurs in Scotland, on Ben Lawers, 

 according to Jones. 



Deducting the species that are mainly or entirely confined in 

 their distribution either to Greenland or to Arctic countries, the 

 majority at least of the remainder occur on the Scandinavian Alps, 

 and many of them on the Alps of Scotland and Switzerland, or 

 generally on those of continental Europe ; while a considerable 

 number are common British forms. Some Lichens, which are 

 -only alpine in Britain (Scotland), occur, as might be expected, at 

 low elevations, and even on or near the sea-level, in Green- 

 land {e.g., Thamnolia vermicularis, which is abundant in the 

 Jakobshavn district, on or about the coast). 



The non-British species are the following : — 



Alectoria divergens. Lecauora Jungermanniae. 



Cladonia caiiieola. turfacea. 



cyanipes. nimbosa. 



Cetraria odontella. mniaraea. 



Nephroma arcticum. Lecidea alpestris. 



papyraceum, aglsea. 



Parmelia centrifuga. elata. 



Umbilicaria anthracina. geminata. 



hirsuta. obscurata. 



spodochroa. fuscescens. 



Squamaria chrysoleuca. cuprea. 



straminea. cinnabarina. 



Lecanora chlorophona, leucorsea. 



epanora. squalida. 



oreina. Endocarpon d^daleum» 



peliscypha. Verrucaria mucosa, 



molybdina. clopima. 



A comparison of the Greenland Lichen-flora with that of Arctic 

 America (assuming Leighton's Catalogue of Sir John Richard- 

 son's collections in 1826 J to be representative of the Arctic- 

 American Lichen-flora), shows that there exists a considerable 

 difference in the elements of which they are respectively made 

 up. There are certain genera and species in Arctic America 

 that do not occur in Greenland, while there are in Greenland 

 at least many species that do not occur in Arctic America. The 



* "Northern Lichen-Flora," p. 370. f Ibid., p. 372. 



% Apparently during Franklin's Second Land Expedition, 1825-6. — Journal 

 of Linneau Society, vol. ix. Botany, p. 184. 



T 2 



