CETRAMA. 



159 



have depended on the medicines with which it was combined. 

 Its medicinal properties were probably first recognized in 

 Iceland, and were known to Danish apothecaries so early as 

 1673. In 1683 Hiarne lauds it in the haemoptysis, or 

 blood-spitting of phthisis. It is still imported in compara- 

 tively large quantities into Britain via Hamburg and Got- 

 tenburg; in 1836 no less than 20,000 lbs. paid duty. It 

 might be extensively gathered for commercial purposes on 

 our Scotch mountains. And, lastly, the brown colouring- 

 matter of its thallas has been applied by the Icelanders to 

 the dyeing of woollen stuffs.* 



6. Cetraeia aculeata {aculeus, a prickle). Thallus 

 somewhat fruticulose, rigid, chestnut-coloured, cartilaginous, 

 dichotomously or irregularly and very much branched ; laci- 

 nise divaricate, terete or flattened, smooth or roughish, stel- 

 lulate or bifurcate at extremities; apothecia chestnut-co- 

 loured, terminal, having a thalline, ciliate-denticulate margin. 



A comparatively common species growing on the ground, 



* Cramer, De Usu Lichenis Islandici, Erlangen, 1780 : Ebeling, de Quassia 

 et Cetraria Islandica, Glasgow, 1779 : Davidson on removal of bitter taste 

 and lichen ous odour of Iceland Moss, 'Jameson's Journal/ 1840: and 

 Transact, of Edin. Soc. of Arts, June 20, 1838 : Proust in Journal de 

 Physique, vol. iii. 



