804 ORD. LIV: Alge. LICHEN ISLANDICUS. 
THIS Lichen is foliaceous, erect, largé: the leaves are crowded, 
connected together, tough, membranous, two or three inches long, 
variously sinuated, or divided into irregular blunt lobes, turned in 
at the edges, and frin ged with short strong bristles: the surface is 
smooth, shining, channelled, and of a oe green or brown colour: 
the fructifications or scutella are large, of a reddish brown colour, 
and placed on the lobes of the leaves. It is a. native of Britain, 
particularly onthe mountains of Wales and Scotland. 
The medicinal qualities of the Lichen Islandicus have lately 
been so well established at Vienna, that this plant is now admitted 
into the Materia Medica of the Edinburgh Pharmacopeia. It is 
extremely mucilaginous, and to the taste is bitter and somewhat 
astringent: its bitterness, as well as the purgative quality which 
it manifests in its recent state, are In a great measure dissipated 
on drying, ‘or may be extracted by a slight infusion in water, so 
that the inhabitants of Iceland convert it into a. tolerably g grateful 
and nutritive food. An ) ounce of this Lichen, boiled a quarter of 
an hour ina pint of water, yielded. seven 0 ounces of a mucilage as 
thick as that procured by the solution of one part of oar arabic 
in three of water. 
The medical virtues of this Lichen were probably first learned 
from the Icelanders, who employ it in its fresh state as a laxative, * 
but when deprived of this quality, and properly prepared, we are 
told that it is an efficacious remedy in consumptions, coughs, 
dysenteries, and diarrheas. Scopoli seems to have been the first 
who of late years called the attention of physicians to this remedy 
in consumptive disorders ;* and further instances of its success are 
related by Herz," Cramer,‘ Tromsdorff,° Ebeling,’ Paulizky,* Stoll,* 
* See Borrichius in Bartholini, Act. Med. Hafn. 1761. p.126. Olafsen Reise 
igiennem Island. tomt. ¢. p. 159. . 
> Ann. hist. nat. t. 1769. p. 112. § Py oe ii. p. 141. - 
¢ Briefe an Verzte, vol. 2. 4 © Diss, de Lichene Islandico, 
£ Diss. de Quassia et Lichene Islandico, 
& Med. Pract. Beob. 2. Sammi. 104. 
| * Rat. Med, P. 2. a 
