SECTION IV. REPRODUCTION 

 CHAPTER IX 



VEGETATIVE AND SEXUAL REPRODUCTION 



Reproduction is a general term used to designate the various 

 processes by which a parent organism gives rise to new organ- 

 isms, called offspring or children. Reproduction is fundamen- 

 tally a cellular process and consists in all cases in the separation 

 of single cells or cell masses from a parent or parents, which 

 possess the power of growth and differentiation to form new 

 individuals. Two distinct kinds of reproduction occur in the 

 higher plants, which are designated as vegetative and sexual re- 

 production. In vegetative reproduction the cell masses which 

 give rise to new organisms are usually much less highly special- 

 ized than in single sex cells which unite in sexual reproduction. 

 The results of the two processes are also quite different in their 

 nature and importance to man, as we shall observe in the 

 discussion which follows. 



VEGETATIVE REPRODUCTION 



Vegetative reproduction in the higher plants takes place 

 exclusively by means of vegetative structures. These may be 

 parts of ordinary roots, stems, and leaves. or they may be highly 

 modified parts of the plant body, represented by bulbs, tubers, 

 corms, etc. 



STEMS 



One of the simplest forms of vegetative reproduction is that 

 of budding and layering, in which ordinary buds and shoots form 

 the starting points for the production of new individuals. In the 

 black raspberry (Fig. 75) and the strawberry (Fig. 76), layering 



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