THE LICHEN FAMILY. 



511 



pastures, and a very few only mingle with the wild-flowers and grasses 

 on the hedge-banks. Their favourite habitats are rocks and stones, 

 many kinds seating themselves on the old monuments in rustic church- 

 yards, and on the ruined walls of castles and abbeys, where their 

 beautiful patches of grey or yellow incrustation mingle " time-stains " 

 with the ivy. Many species cling to the bark of trees, especially such 

 as are aged and decrepid, clothing them as if with a permanent hoar- 

 frost, or with rough and shaggy beards, that in winter make them look 

 tattered and spectral. These latter are the species commonly called 

 " tree-moss," often so elegantly alluded to by the poets, as in the 

 opening lines of " Evangeline." They grow in every part of the world, 

 braving the inclemencies of every climate, and ascending to a higher 

 level above the sea than any other plants ; and, independent of seasons. 



Fig. 228. 

 Parmelia pulverulenta (on a piece of bark). 



when other plants are denuded, or gone to decay, (the mosses, the 

 fungi, and a few evergreen trees alone excepted) their diversified hues 

 and crowds of pretty cups " make glad the solitary place." In figure 

 they are often singularly beautiful. A very common hedgerow species, 

 called " fairies' wine-cups," consists of tiny gray goblets ; another, 

 equally common, growing on heaths, shoots up in silvery sprays among 

 the moss, like a little shrub ; others resemble tiny pillars, with scarlet 

 capitals. The " letter-hchens," constituting the genera Graphis and 

 Opcgrapha, and inhabiting the smooth bark of trees, resemble inscrip- 

 tions in Arabic or Hebrew. Coming upon them in the depths of the 

 " unfrequented woods," we might almost fancy their pretty writing the 

 literatm-e of the Dryads, — pastorals telling the pleasures of rural life. 



