FILIX MAS. 371 



root fibres, of Aspidium Filix mas. Collected in 

 summer. 



Characters. Tufted, scaly, greenish brown ; powder greenish- 

 yellow, with a disagreeable odour, and a nauseous, bitter, some- 

 what astringent taste. 



Preparation. 



Extractum Filicfc Llquidum. " Oil of Male Fern." Male 

 Fern, 1 ; Ether, 2. Percolate, and distil of!, the 

 ether. Dose, 30 to 60 min. 



Composition. Male fern contains a colourless crystalline I 

 body, filicic acid, fixed and volatile oils, tannin, resins, and the I 

 ordinary constituents of plants. Which may be the active I 

 principle is uncertain. 



ACTION AND USES. 



Male fern is an active anthelmintic, peculiarly destructive 

 to the tape- worm. It is less irritant to the stomach and bowels 

 than cusso and kamala, and should be preceded and followed by 

 a purgative. It is, on the whole, the most successful of anthel- 

 mintics when properly employed. 



UCHENES. 



Cetraria ICELAND Moss. The entire lichen, 

 Cetraria islandica. Native of the north of Europe. 



Characters. Foliaceous, lobed,crisp,cartilaginous, brownish- 

 white, paler beneath; taste bitter, and mucilaginous. A strong 

 decoction gelatinises on cooling. 



Composition. Cetraria contains 10 per cent, of starch; 

 20 per cent, of lichenin, C 6 H 10 6 , a starch-like powder, not 

 striking blue with iodine ; and two bitter acids cetraric acid, 

 id lichenstearic acid, 



Preparation. 

 Decoctum Cetrarise. 1 to 20. Dose, 1 to 2 fl.oz. 



ACTION AND USES. 



Iceland moss is at once a bitter tonic and nutritive sub- 

 stance, but is not in general use as either. 



