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POPULAR, HISTORY OF LICHENS. 



It grows on the trunks of old trees, and also sometimes 

 on rocks or the ground ; it has been mentioned as occur- 

 ring on the south coast of England, on the Malvern Hills, 

 and on Ailsa Craig in the Mrth of Clyde, but it is a rare 

 species in Britain. Its cortical layer is very dense, con- 

 sisting of almost solid, cylindrical filaments very closely 

 united : iodine communicates to it a rich blue colour. It 

 is the seat of a beautiful yellow colouriug matter, probably 

 similar to that of the following species, and has apparently 

 been similarly employed in dyeing. 



4. Cornicularia vulpina {vuljoes, a fox). Thallus citron- 

 coloured, divaricate-ramose, linear ; extremities filiform ; sur- 

 face sometimes pulverulent or sorediiferous ; apothecia chest- 

 nut-coloured or blackish, but very rare. 



Its habitat is the bark of fir-trees in alpine or sub-alpine 

 regions ; but it appears only recently to have been recog- 

 nized as a native of Britain, having been found on the Kil- 

 leney Hills, county Dublin, Ireland. It possesses a very 

 dense, horny cortical layer, of which the cellular elements 

 can scarcely be recognized ; and also a firm central axis or 

 cylinder, formed of solid filaments closely associated. Its 

 cortical layer contains, disseminated through it in the 

 form of small grains of a resinoid appearance, a beautiful 



