329 



of the world : thus, the Lichens of North America differ little from those of 

 Europe. F6e 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 medicinal- 

 ly 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 

 vegetable 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 tcu-tarea, or Cudbear, hsematomma and atra, Variola- 

 ria lactea, Urceolaria scruposa and cinerea, Isidium Westringii, Lepraria chlo- 

 rina ; of the foliaceous species, Parmelia saxatilis, omphalodes, cncausta, con- 

 spersa, and parietina, Sticta pulmonacea, Solorina crocea, and Gyrophora deu- 

 sta and pustulata ; but the most important are Roccella tinctoria and fusifor- 

 mis, 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, Alec- 

 toria jubata, Ramalina scopulorum, and several Cenomyces. The nutritive 

 properties of Lichens probably depend upon the presence of an amylaceous 

 substance analogous to gelatine, which, according 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 bitter as well as mucilaginous, and is frequently used as tonic, demul- 

 cent, and nutrient ; Cetraria nivalis, Sticta pulmonacea, and Alectoria usne- 

 oides, will all answer the same purpose. Tripe de Roche, on which the Cana- 

 dian hunters are often forced to subsist, is the name of various species of Gyro- 

 phora : the Rein Deer Moss, which forms the winter food of that animal, is 

 Cenomyce rangiferina. Parmelia parietina, Borrera furfuracea, Evernia pru- 

 nastri, Cenomyce pyxidata and coccifera, are reputed astringents aud 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 confirma- 

 tion. See Decand. Essai M.6d. 318, and Jlgardh Aph. 94. 



Examples. Parmelia, Sticta, Ramalina, Nephroma, Boeomyces, 



CCLXXI. FUNGI. The Mushroom Tribe. 



Fungi, Juss. Gen. 3. (1789); Dec. Fl. Fr. 2. 65. (1815); Nees das System der Pilze und 

 Schwamme, (1817); Fries. Syst. Mycolog. (1821); Syst. Orb. Veg. (1825); Adolphe 

 Brongn. in Diet. Class. 5. 155. (1824) ; Grev. Scofl. Crypt. Ft. 6. (1828); Hooker British 

 Flora, 457. (1830). — Epiphyt-e, Link; Grev. Fl. Edin. xxv. (1824); Gasteromyci, Grev. 

 Fl. Edin. xxiv. (1824).— ByssoidejE, Grev. Fl. Edin. xxv. (1324); Fries Syst. Orb. Veg. 

 (1825) ; Grev. Scott. Crypt. Fl. 6. (1828).— Mycetes, Spreng. Syst. 4. 376. (1827).— Ube- 

 oine£, MucEDrNEJE, and Lycopehdace^:, Ad. Brongn. in Diet. Class. I. c. (1824.) 



Diagnosis. Aerial, leafless, flowerless plants, with no thallus or external 

 sporuliferous disks. 



52 



