10 GENERAL NATURE OF PLANTS. 



in which, however, the similar parts of the 

 stock and scion must be brought into close con- 

 tact, and kept so for some time, and this must 

 be done during the growing season. 



Woody fibre conveys fluid in the direction 

 of its length, gives stiffness and flexibility to the 

 general system, and acts as a protection to spiral 

 and other delicate vessels. 



Spiral vessels convey oxygenated air. 



Other vessels probably conduct fluid when 

 young, and air when old. 



As the bodies of which all tissue is composed 

 are perfectly simple, unbranched, and regular 

 in figure, having, when elongated, their two 

 extremities exactly alike, they are more or less 

 capable of conveying gaseous matter or fluids 

 in any direction ; and, consequently, a current 

 may be reversed in them without inconven- 

 ience : hence, inverted cuttings or stems will 

 grow. 



All parts of plants are composed of tissue, 

 whether they be soft, as pulp ; or hard, as the 

 bony stone of a Peach. 



With regard to Horticultural operations, the 

 parts of plants should be considered under the 

 heads of Root, Stem, Leaf -buds, Leaves, Flow- 

 ers, Stamens and Pistils, Frmt, and Seed. 



