CHAPTER IV. 

 PLANT MANIPULATION. 



Section I. Plajstt Propagation. 



340. Propagation, as the term is generally used in 

 plant culture, is the artificial multiplication of plants, 

 i. e., reproduction (16) encouraged or induced by the 

 knowledge, skill and care of the cultivator. 



Theoretically, any part of a plant containing living 

 cells, with sufficient prepared food or tissue capable 

 of preparing food (58) may under proper conditions 

 develop into a complete plant. But in practice, we have 

 not been able to fully demonstrate this theory; for ex- 

 ample, the roots and leaves of some plants have not 

 been induced to form buds. 



341. Plants are Propagated by Numerous Methods, 

 but only two of these are distinct in kind, viz., by seeds 

 {or spores), and by division of the plant. In propaga- 

 tion by seeds, the embryo of the seed (53) is the vital 

 center whence the new plant is developed. In propa- 

 gation by divison, a living bud (127) from the parent 

 plant, or a bit of tissue capable of forming a bud, is 

 substituted for the epabryo of the seed. In seed propa- 

 gation, the resulting plant is the product of sexual 

 fecundation (149), and hence cannot be considered as 

 strictly a part of the parent only. It does not neces- 

 sarily resemble the parent closely. In propagation by di- 

 vision, on the other hand, the resulting plant may be 



(190) 



