CHAPTER XIV 



FUNDAMENTAL PRINCIPLES 



161. Two Kinds of Reproduction. — In the two preced- 

 ing chapters attention has been called to three ways of ob- 

 taining new fern-plants, namely, by spores, by vegetative 

 multiplication, and by fertilized eggs. The first two 

 methods may be grouped together as asexual, while the 

 second is sexual, as shown in the following table. 



By the giving off of ' 

 Asexual, in- multi-cellular por- 

 volving ceU- tions or outgrowths 

 divisions i of vegetative tissue, 

 only. By the giving off of 



special reproductive 

 bodies of one or few 

 cells, called spores. 



Reproduction - 



Sexual, in- 

 volving cell- 

 fusions. 



Artificial (slips, 

 cuttings, etc.)- 



Natural (tubers, 

 bulbs, gemmse). 



162. Vegetative Multiplication. — Vegetative multipli- 

 cation may be accomplished either without or with the 

 intervention of man. In the first case the plant produces 

 special reproductive bodies such as tubers, bulbs, offsets 

 and stolons, which become separated from the plant with- 

 out assistance, and develop into new individuals. In 

 the second case a similar result is accomplished through 

 the removal by the gardener of portions of the parent 

 plant, such as slips, cuttings, leaves {e.g., in the begonia), 

 or by bending branches over until they touch the ground, 

 and there take root, after which the newly rooted portion 

 may be severed from the parent plant. This is called 

 layering. The production of new individuals by the arti- 



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