190 



POPULAR HISTORY OF LICHENS. 



areola; in general appearance they resemble the nascent 

 apothecia, which however have no areola and are less de- 

 pressed at the apex. 



2. Parmelta perlata. Thallus greyish-glaucous, mem- 

 branaceous, frequently sorediiferous, especially at margins, — 

 below brownish-black, somewhat naked ; lacinise imbricate- 

 lobate; lobes naked or ciliate at margins. Apothecium tur- 

 binate, chestnut-coloured. (E. B. 341.) 



A comparatively common corticolous and saxicolous spe- 

 cies in lowland and subalpine districts ; it is rare however 

 in fructification. Specimens in fine fruit may be seen in 

 Tuckerman's 'Lichenes America Septentrionalis exsiccati' 

 (1847). On ammoniacal maceration it yields a fine orchill; 

 and for the manufacture of orchill it is imported to a consi- 

 derable extent into London, from the Canary Islands, under 

 the name of " Canary Rock-moss." It occurs likewise on 

 the Himalayas, in Ceylon, and other parts of the world. 



3. Parmelia caperata (capero, to wrinkle). Thallus 

 ochroleucous, membranaceous, frequently granulose-pulve- 

 rulent above, — below blackish, rough, at length rugose- 

 plicate. Apothecium chestnut- coloured ; margin crenulate, 

 pulverulent. (E.B. 654.) 



Also a common corticolous and saxicolous species in low- 



