LICHENS. 207 



There are numerous other species of this family, but 

 only these have rewarded our research. 



Of the genus Placodium we have never succeeded in 

 finding a specimen. 



The Parmelia group contains some handsome and 

 showy species, the theme alike of poets and lovers of 

 nature. The fronds are scaly in the middle, and attached 

 by fibres or a narrow vase to the substance on which 

 they grow, but they are free for the remainder of their 

 breadth, lobed and veined, and have a full claim to rank 

 as frondose lichens. Upon poles, near the Dever, in 

 Wiltshire, we found the Sulphur Parmelia (P. caperata, 

 Plate XIV., Jig. 17). It is a handsome spreading 

 lichen, powdery and pale yellow above, dark brown and 

 hairy beneath. Brown is the colour of the apothecise, 

 but our specimens had no fruit upon them. 



The Crotal or Crostal of Ireland and Scotland is a 

 member of this family (P. omphalodes, Plate XIV., Jig. 

 18). I first saw it upon rocks in the "black country," 

 bordering Lord Breadalbane's deer park in the Western 

 Highlands. It is a wonderful district : and as the coach 

 wound slowly up the steep road, constituting, as the 

 driver informed us, "the highest travelling ground in 

 Scotland," we noticed dark bronze patches on the surface 

 of the gray rocks. We had passed the pine groves, and 

 the herds of shy deer and the shooting lodge beyond, and 

 had come into a land of peat bogs, black, as if drained 

 from coal-pits, and brown heath, and rugged rocks, — no 

 green in moss or grass, no flowers, no gay colouring. 

 Here it was that the Crotal was flourishing, its leafy 

 patches forming glossy stars of brown madder. It is 



