LICHEN'-rLORA OP iH"ORTnEr.y EUPtOPE. 403- 



or frutlcose vegetation*. "Undoubtedly this is one of the main 

 causes of the paucity of the lichens of Iceland. It would be 

 natural to suppose that the rugged, hard, recent lava would be one 

 of the last supports of a lichenose, or higher, vegetation. But that 

 such is not altogether or necessarily the case Avas long ago noticed 

 oy Sir Charles Lyell in regard to Etna, Vesuvius, and the Canary 

 Islands alike j and similar observations have been made by other 

 travellers in other volcanic countries. Sir Cfiarlea describes Li- 

 chens as the first characteristic vegetation of modern lavas, espe- 



• n • 



cialiy species of Stereocaitlon^ which arc sometimes so plentiful as 

 to lohten the lava ; and he remarhs, " The natural growth, even of 

 a cryptogamous vegetation, although restricted to limited areas, 

 on lava of sucli recent date is Avorthy of notice, and seems to give 

 promise of an early fertility for the future^f, I have already re- 

 lerred to the apparent parallelism which exists between the deserts 

 of Iceland and the " Tundras " of Laj^land, especially what Baer 

 describes as the " Plechtentundra " (whereon lichens are the do- 

 mmant forms of vegetation), which is brown, dry, and arid, as 

 compared with the " jVIoostundra " (whereon mosses predominate 

 over other forms of vegetable life), which is comparatively moist 

 and green. On these North-Eussian deserts rdlman also refers 

 to the paucity of 'Lichevi'Sj^ecies though not of individuals — a. 

 paucity which he attributes, apparently with justice, to the absence 

 of forests. The lichen- vegetation of these treeless wastes, as de- 

 scribed by rdlmanj- — and which consists of species of Cladonia, 

 ^tereocaxdon^ JPlatysma^ and Cetraria, covering whole tracts of 

 country — -resembles that (of many parts at least) of Iceland. 



The Faro Islands are trappean, and are comparable — quoad their 

 geological constitution and physical configuration — with certain 

 «f the Scottish Islands, such as ilull and Skye, and certain districts 

 of the Scottish mainland, such as Arthur's Seat and the Braid IlilJs 

 ^car Edinburgh, or the Sidlaw and Ocliil Hills near Perth §. Their 

 Lichen-flora is more allied to that of Iceland than of iVorway. 

 "VVhen we possess a full list of the lichens of the Fiiro group, on 

 tlie one hand, and the Shetland Islands, on the other, there will 



The exceptions consist mainly of patches of stunted birch bushes in some 

 parts of tlie country. 



t Memoir on *< The Lavas of Mount Etna," Philosoph. Transact, part 2 for 

 1S58, p. 726, 



X "Toyage botanique dans la Laponic orientalc," by SL X. I. FcUman, IJuII, 

 de la See. Botan. do France, Nov. 27, 18G3. 



§ The greatest elevation in Fiiri) is the hill called SlatfarctincT, which is about 

 20OO feet liigh. 



