USES OF LICHENS. 



83 



In mediaeval medicine, in this and other countries, the 

 Lichens were used to a considerable extent, chiefly as nu- 

 trients, demulcents, febrifuges, astringents, tonics, purga- 

 tives, and anthelmintics. Not a few were supposed to 

 be endowed with specific virtues, such as the common 

 Peltigera canina, which formed the basis of the celebrated 

 " pulvis antilyssus/' or " pulvis contra rabiem," long re- 

 garded as a sovereign cure for hydrophobia. At the pre* 

 sent day in this country only one species is used to any 

 extent, as a nutrient and demulcent, in various dyspeptic 

 and chest affections — the Cetraria Islandica, or "Iceland 

 Moss," immediately above alluded to, which is to be met 

 with in all our druggists' shops. The virtues of Lichens in 

 medicine are certainly more imaginary than real, though they 

 appear to possess to a small extent some of the properties 

 attributed to them. Their nutritive and demulcent properties 

 depend on the presence of the starchy and gummy matters 

 already mentioned. Several species yield to boiling water 

 a jelly, which, when deprived of certain bitter substances, 

 which are also extracted by the water, and flavoured with 

 sugar and spices, mixed with coffee, or forming the basis of 

 soups, constitute very light and agreeable articles of diet ; 

 such are Cetraria Islandica, Sticta pulrnonaria, and some 



