VEGETATIVE PROPAGATION 



219 



repens), and the Common Horsetail (Equisetum arvense) are cases in 

 point. Any node serves to provide new buds ; and as the long under- 

 ground rhizomes are broken 

 up in preparing the soil, this 

 does not eliminate, but tends 

 to spread the weed. 



It thus appears that vege- 

 tative extension and propa- 

 gation of the individual is a 

 very wide-spread feature, both 

 in Flowering Plants and in 

 those lower in the scale. It 

 is effective in wild life, as 

 well as under the hand of the 

 gardener. A very consider- 

 able proportion of the per- 

 ennial plants which we see 

 have been so produced. This 

 applies especially to the 

 Grasses and Sedges, whose 

 perennial rhizomes are con- 

 stantly growing forward, and 

 as constantly rotting pro- 

 ressively from the base. But probably the most prominent, and at 

 ic same time familiar example of all is the Bracken Fern, which covers 

 imense areas all over the world. Its underground rhizomes branch 

 sly ; if a single specimen be dug up, and followed backwards, the 

 jrown region of decay is soon reached. Young seedling Brackens 

 re rarely met with in the open. Here then is a case where the apical 

 rowth and branching of the individual are practically unlimited, and 

 /here its vegetative increase in number of physiologically independent 

 lits appears to be unlimited too. It may be held as a type of that 

 /egetative spread and multiplication which, though it involves no 

 jecial development for the purpose, is frequent among perennial 

 jlants. . 



FlG I67 



f leaf of Gloxinia, bearing adventitious buds 

 after cultivation, in heat, on moist soil. 



