333 



Lichens follow these, and then Mosses and Hepaticse. D'Urville Ann. Sc. 

 6. 54. About 800 species are described by Acharius, the number of which 

 is perhaps capal)le of some reduction ; 200 are added by Fee, and great 

 numbers are, no doubt, still undiscovered. They are found upon trees, rocks, 

 stones, bricks, pales, and similar places ; and the same species seem to be 

 found in many different parts of the world : thus, the Lichens of North America 

 differ little from those of Europe. Fee estimates the number actually known, 

 either in herbaria or in books, at 2400. 



Properties. Lichens have been remarked by Decandolle to possess two 

 distinct classes of characters, the one rendering them fit for being employed 

 as dyes after maceration in urine, the other making them nutritive and 

 medicinally useful to man. M. Braconnot has ascertained that oxalate of 

 lime, or oxalic acid, exists in great abundance in Lichens, particularly in 

 those which are granular and crustaceous. The common Variolaria, which is 

 found upon almost every old beech-tree, contains rather more than 29 per 

 cent. Ed. P. J. 13.194. Lichens that grow on the summit of fir-trees have been 

 found by Dr. John, of Berlin, to contain an uncommon proportion of oxide of 

 iron, which may be viewed as illustrative of the formation of iron by the vege- 

 table process. Ibid. 2. 394. Of those used in dyeing, the principal crusta- 

 ceous kinds are, Lecanora perella, the Orseille de terre, or Perelle d'Auvergne 

 of the French, Lecanora tartarea, or Cudbear, hsematomma and atra, Vario- 

 laria lactea, Urceolaria scruposa and cinerea, Isidium Westringii, Lepraria 

 chlorina; of the foliaceous species, Parmelia saxatilis, omphalodes, encausta, 

 conspersa, and parietina, Sticta pulmonacea, Solorina crocea, and Gyrophora 

 deusta and pustulata ; but the most important are Roccella tinctoria and 

 fusiformis, the dye of which is so largely used by manufacturers under the 

 name of Orchall, or Archil, or Orseille des Canaries ; there are other 

 species capable of being employed in a similar manner, as Usnea plicata, 

 Evernia prunastri, Alectoria jubata, Ramalina Scopulorum, and several 

 Cenomyces. The nutritive properties of Lichens probably depend upon the 

 presence of an amylaceous substance analogous to gelatine, which, accord- 

 ing to Berzelius, exists in the form of pure starch or amylaceous fibre, 

 to the amount of 80-8 per cent in Cetraria islandica. This plant, which is 

 the Iceland Moss of the Shops, is slightly bittei; as well as mucilaginous, and 

 is frequently used as tonic, demulcent, and nutrient; Cetraria nivalis, Sticta 

 pulmonacea. and Alectoria usneoides, will all answer the same purpose. 

 Tripe de Roche, on which the Canadian hunters are often forced to subsist, 

 is the name of various species of Gyrophora ; the Rein Deer Moss, which 

 forms the winter food of that animal, is Cenomyce rangiferina. Parmelia 

 parietina, Borrera furfuracea, Evernia prunastri, Cenomyce pyxidata and 

 coccifera, are reputed astringents and febrifuges, and Peltidea aphthosa an 

 anthelmintic ; Sticta pulmonacea is used in Siberia for giving a bitter to beer ; 

 Evernia vulpina, called Ulfmossa by the Swedes, is believed by that people 

 to be poisonous to wolves; but this requires confirmation. See Decand. 

 Essai Med. 318, and Agardh Aph. 94. 



Examples. Parmelia, Sticta, Ramalina, Nephroma, Bixomyces. 



