260 HARMONIES OF VEGETATION. 



vision, however, is made for this failing: daring the winter, the 

 vitality of the tree is in its least developed state, consequently de- 

 rives sufficient air by absorption with the nutriment of the root : 

 as spring comes on, the life of the plant is invigorated, abundance of 

 leaves are sent forth, and thus an additional surface for absorption 

 of air and moisture is created, to meet the increasing demands to 

 support life. 



18. The grand support of the plant, however, is 

 chiefly that of absorption by the root. 



The fluids existing in the soil when absorbed by the root, are 

 designated by the appellation of sap or lymph ; which, before it can 

 be rendered subservient to the purposes of vegetable nutrition, 

 must either be intermediately conveyed to some viscus proper to 

 give it elaboration, or immediately distributed throughout the whole 

 body of the plant. 



FUNCTIONS OF PLANTS. 



19. As plants are organized bodies requiring food 

 and air to support them, they are therefore endowed 

 with absorbing, circulating, and excretory functions. 



Plants are very similar in their functions to animals, requiring 

 food to nourish, organs to convey and alter the food received, and a 

 structure to inhale air and to expel adventitious particles. 



20. The absorbing process is principally effected by 

 the root and leaves. 



The root is the grand organ by which plants extract nourishment 

 from the earth j while the leaves, and even the surface of the whole 

 plant are calculated to absorb moisture and air from the surrounding 

 atmosphere. 



21. The nourishment or support of vegetable life, is 



