180 
LICHEN ISLANDICUS. 
more or less common on all the mountainous heaths and woods of 
the north of Europe : it has also been found growing in great abun- 
dance in the Asturias.* 
Iceland liverwort, or moss, grows to the height of about two or 
three inches, large, erect, bushy, crowded and connected together ; 
the frond is tough, dry, coriaceous, lobed and sinuated ; the lobes 
are variously lacinated, turned in at the edges, and the margins 
beset with short strong bristles; their surface is smooth, shining, of 
a pale green or brown colour, above concave, beneath convex ; the 
fructifications or shields are large, of a reddish brown colour, and 
placed on the lobes of the leaf or frond. 
Sensible and Chemical Properties, &c. Iceland liver- 
wort is inodorous ; its taste is mucilaginous and slightly bitter. The 
dried plant, in appearance, resembles the recent ; it is neither very 
tough or brittle, but in the former state it is more pulverizable. 
When macerated in water, it absorbs more thap its own weight of 
the fluid ; the watery infusion made with boiling water is inodorous, 
of a pale yellowish colour, and bitter taste. Lichen macerated in 
water, and afterwards boiled, aflFords a decoction which thickens as it 
cools, and becomes a tremulous jelly resembling starch; after some 
time the jelly cracks, separettes from the watery part, and dries into 
semi-transparent masses, which are soluble in boiling water, but not 
in cold, and may be again precipitated by infusion of galls. The 
watery infusion is changed red by sulphate of iron : according to 
the analysis of Proust, Lichen affords about one-third of starch, 
and two-thirds of a substance insoluble in hot water, resembling the 
gluten of wheat, with a small quantity of a bitter extractive matter. 
Medical Properties and Uses. Iceland moss is esteemed 
demulcent and tonic. It appears to have been employed for a long 
period in Sweden as a popular remedy in coughs and pulmonary 
disorders, in which diseases it is noticed by Linnaeus ; but the 
attention of physicians was not excited to this remedy until Scopoli 
published his observations on it in the year 1769; subsequently 
several instances of its good effects in consumptive disorders were 
related by many of the continental physicians, viz. Cramer, Troms- 
dorfF, Stoll, Herz, and others, who not only recommended it in 
phthisical cases, but in dysentery, malignant fevers^ worms, &c. 
Although the remedial effects of this plant have not answered the 
expectations that were first formed of it, nevertheless as a palliative in 
_* JToarn. de Physique, 1806. 
