RAMBLES 



IN 



Stmth of llotucdcss 



o 01 



CHAPTER XXL 



LICHENS. 



" The living stains which Nature's hand alone, 



Profuse of life, pours forth upon the stone ; 



For ever growing ; where the common eye 



Can but the bare and rocky bed descry ; 



There Science loves to trace her tribes minute, 



The juiceless foliage, and the tasteless fruit ; 



There she perceives them round the surface creep, 



And while they meet, their due distinction keep ; 



Mix'd, but not blended, each its name retains ; 



And these are Nature's ever-during stains ! " 



Crabbe. 



I CHENS are plants coming next to the Mosses 

 in botanical order, though differing widely 

 from them in appearance. They are distin- 

 guished from seaweeds by the presence of minute green 

 bodies (gonidia), lying generally in a layer between the 

 upper and lower covering of the plant. The infant 

 lichen first appears as a frail network upon the stone or 

 bark, a layer of cells grows upon this, and then the gonidia 



