CRYPTOGAMIA. 43 



Irence it is observed, that trees which are annually 

 cleared from the moss grow nearly twice as fast. 



ORDER 3. 



REIN-DEER LICHEN. Upon this vegetable alg,e , 

 the numerous herds of Rein-deer, the only riches of r i ags . 

 the sequestered Laplander, are entirely dependant for 

 their winter food. In that remote region it grows at 

 least a foot high, covering the ground like snow. In 

 England it is less luxuriant, seldom attaining to half 

 that height. 



In grass fields and on gravel walks, after rain, it 

 is not uncommon to find a gelatinous substance, vul- 

 garly supposed to be the remains of a meteor, or 

 fallen star. This is a vegetable production belonging to 

 this natural Order Algae ; its botanical name is Tre- 

 mella nostoc. 



Of this Order belongs the Genus Fuci, many of 

 which have no root, but float on the surface of the 

 water, and are entirely nourished by their leaves. The 

 Byssus, another Genus of this Order, may be consi- 

 dered as the last in the scale of vegetation, of which 

 there are many species. They appear in form of 

 threads, or a kind of meal, on rotten wood, the bark of 

 trees, rocks, damp banks, and walls, especially of 

 damp cellars. On stagnant waters there is often a 



