CHAPTER IX 

 REPRODUCTION IN PLANTS 



The synthetic act by which the organism maintains itself is 

 fundamentally of the same nature as that by which it repairs 

 itself when it has undergone mutilation, and by which it multi- 

 plies and reproduces itself. Bernard 



AMONG the lowest members of the plant kingdom the body 

 consists of but a single cell; the individual and the cell are 

 identical. As has been seen irr Sphaerella, all the life pro- 

 cesses essential to the individual are exhibited in relative 

 simplicity and without obviously complicated machinery. 

 Moreover, the continuation of the race is provided for by the 

 individual cell dividing to form two new cells. Neglecting 

 for the time being the mechanism of cell division, it is clear 

 that reproduction in Sphaerella, since it is not complicated by 

 specialized organs for its performance, is a comparatively 

 simple process. 



We have considered briefly the gradual increase in com- 

 plexity of the plant body from the unicellular condition, 

 through colonies of essentially similar cells and the thallus 

 type, to that of the higher vascular plants, placing emphasis 

 on organs directly or indirectly associated with nutrition. 

 It is necessary now to review in a similar manner the speciali- 

 zations of structure and function which exist in the plant 

 kingdom for the multiplication of individuals. 



It may be well to reiterate here that reproduction and 

 growth are phenomena which are intrinsically the same 

 both are the result of a preponderance of the constructive 



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