VEGETATIVE PROPAGATION 253 



rhizomes are constantly growing forward, and as constantly rotting 

 progressively from the base. But probably the most prominent, and 

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

 covers immense areas, and is widely spread all over the world. Its 

 underground rhizomes branch freely ; if a single specimen be dug up, 

 and followed backwards, the brown region of decay is soon reached. 

 Young seedling Brackens are rarely met with in the open. Here then 

 is a case where the apical growth and branching of the individual are 

 practically unlimited, and where its vegetative increase in number of 

 physiologically independent units appears to be unlimited too. It 

 may be held as a type of that vegetative spread and multiplication 

 which, though it involves no special development for the purpose, 

 is frequent among perennial plants. 



