TJMBILICAUIA. 



179 



from particular localities, are said to yield violet and red 

 dyes ; others, or perhaps the same, are used, as in Iceland, 

 to dye woollen stuffs brownish or greenish; and Linnaeus 

 speaks of the variety deusta as yielding a paint much used 

 in Sweden, called " Tousch." In our own experiments on 

 the dyeing properties of Lichens we found many of the 

 Umbilicarias capable of yielding an orchill ; but the var. 

 cylindrica of this species was a remarkable exception, fur- 

 nishing no purple or red tinge on ammoniacal maceration. 



4. Umeiltcaria polyphylla (<pv\\ov } a leaf). Thallus 

 bronze-coloured, below from ochroleucous becoming brown- 

 ish-black, smooth, naked or very finely blackish-pulverulent. 

 Apothecia in young state flat, margined, papillate or having 

 few concentric plicae ; in old state immarginate, becoming 

 convex, having many plicae irregularly aggregated, often dis- 

 posed longitudinally. 



In its most common variety, glabra, the thallus is mono- 

 phyllous or imbricate-lobate, smoothish or naked on both 

 sides, sometimes blackish-pulverulent below ; the apothecia 

 are rarely or never met with. 



A comparatively common species on the granitic rocks 

 of the Highland mountains ; occurring also on hills of 

 minor elevation, as the Cheviots. 



