studied by themselves, as an abstract branch of investigation, 

 without attempting to reason as to their habits from what we 

 know of other organised beings ; still it must never be forgotten 

 that they are living things, possessed, like animals, of vitality, 

 that mysterious force which modifies all chemical and mechanical 

 phenomena, and which so essentially distinguishes the organic 

 world from the brute materials of which it is composed. 



In discussing this subject, it will be most convenient to 

 divide the matter into the heads of, 1. Vital force; 3. Ger- 

 mination; 3. Growth by the Boot; 4. Growth by the Stem; 

 5. Action of the Leaves ; 6. Action of the Flowers ; and, 

 7. Maturation of the Fruit. By this means the life of a plant 

 is traced through all its principal changes, and an opporttmity 

 is afforded of introducing under one or other of these heads 

 every point of information that can be interesting to the 

 cultivator ; who will be most likely to seek it in connection 

 with those phenomena he is best acquainted with by their 

 effects. 



