104 THE ROOT. 



ceive from the leaves of their respective plants, till 

 the former is aroused into action, and the latter are de- 

 manded for use. Like that ofthe alburnum their growth 

 depends on the renovated sap, which has passed and 

 repassed through the vessels of the stem. We see 

 therefore the intimate connexion betwixt the leaf and 

 the root, and perceive why the luxuriance ofthe one 

 should indicate the comparative size and fruitfulneas of 

 the other. 



Bulbous and tuberous plants are usually propagated 

 by separating their roots, and this is the easiest, but 

 not in all cases the most eligible mode of cultivation. 

 When it is pursued, the roots are to be transplanted 

 either in autumn or spring, for at these seasons having 

 no radical fibres to connect them with the earth, their 

 removal does not impede the process of vegetation. 

 There is an exception to this rule, which it would not 

 be deemed necessary to mention, if it did not relate to 

 some ofthe most interesting of our native plants. — The 

 Orchis, and others of the same natural order, have 

 been named as furnishing examples of the palmate or 

 bituberous root. These roots are usually biennial, 

 the oldest portion, bearing the herb and flower of the 

 present season, while its young companion is preparing 

 to succeed it, and to produce the leaves and flowers of 

 another year. When the plant is in full bloom, it may 

 be removed with entire safety, for at this time the ra- 

 dical fibres of the youngest bulb are not formed, and 

 consequently it has no necessary connection with the 

 earth. After this however, as the flower fades, the 

 oldest portion of the root decays and then new fibres 

 are formed, (and the other bulb) which are to supply 

 the plant with nourishment until it blooms again, and 

 these fibres are in all cases an insuperable barrier to 



