during the first year will enable it to produce a much 

 larger number of flowers than is commonly the case in 

 annual plants. In most biennials the food material is 

 stored in some underground part of the plant such as the 

 swollen ' root ' of the turnip or beet, the leaves during the 

 first season forming a tuft or rosette close to the ground. 

 Lastly we have perennials which are much more varied 

 in character than the first two groups of plants. These 

 latter are always comparatively soft in texture, but 

 perennials include both herbaceous and woody forms 

 such as trees and shrubs. The herbaceous again are of 

 two types, firstly those which persist throughout the winter 

 like violets and primroses, and secondly those which die 

 down in the autumn leaving a persistent root or root- 

 stock underground, from which the plant renews its 

 growth in spring. Plants of this kind like the iris, peony, 

 larkspur, Michaelmas daisy and many other favourites 

 of our herbaceous borders have like biennials a large store 

 of food material in their underground organs. This 

 enables them in most instances, not only to produce 

 annually a crop of flowers but to branch out underground 

 and develop into ever-spreading clumps, which in many 

 cases require repeated breaking up and thinning just as we 

 require to cut back our bushes and trees. In some cases 

 these underground portions of perennial plants do not 

 remain attached in one mass, but when the plant dies down, 

 a good deal of the underground part dies away too, leav- 

 ing isolated portions, so that in place of one individual 

 we find many fragments which would seem to be offspring 

 though they are really only remnants of the original 

 parent. Such offsets we have in the case of the tubers of 

 the potato, which represent the rounded swollen ends of 

 underground shoots that have become entirely separated 

 one from the other. Though this is really only a breaking 

 up of the original plant, it is often spoken of as vegetative 

 reproduction but must not be confused with seed reproduc- 

 tion, which is always the result of the fertilisation of 

 flowers. It is important to differentiate these two methods 

 of propagation, particularly as in the case of the potato 

 the tubers used for setting in spring are termed " seed 

 potatoes," though they have really nothing to do with 

 seeds. Vegetative reproduction does not replace seed re- 

 production but is an additional means of propagation, 

 often of the greatest use both in nature and in cultivation. 



