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. 
Reproduction 
Asexual, in- 
volving cell- 
divisions 
only. 
Sexual, in- 
volving cell- 
fusions. 
By the giving off of 
multi-cellular por- 
tions or outgrowths 
of vegetative tissue. 
By the giving off of 
special reproductive 
bodies of one or few 
cells, called spores. 
Artificial (slips, 
cuttings, etc.). 
Natural (tubers, 
bulbs, gemmae). 
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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