i 



56 PEODUonoN OP new varieties. 



please ? Are they not moved by forces outside of themselves, and 

 arranged by these forces according to definite laws? These vari- 

 ations are doubtless produced according to fixed laws, and when 

 we shall have learned these laws, then we may be able to use 

 them in the production of such variations. In the mean time, 

 we can avail ourselves of what we know of the laws which 

 govern the production of varieties by seed, and by directing them, 

 secure new and valuable fruit. 



In order to know how to produce, from seed, varieties of 

 fruit having certain desired qualities, it will be necessary to 



examine the structure of a flow- 

 er, and learn how nature works 

 in the formation of seeds. By 

 looking at Fig. 37, which is a 

 representation of a cherry blos- 

 som cut in two, it will be seen 

 that there are several organs 

 Pig. 37. brought t6 view. Those which 



more particularly concern us just now are those which are called 

 the seed vessel or ovary, the pistil, and the stamen. The pistil, 

 with the ovary at its base, is indicated by the letter c, the knob 

 at the top is called the stigma, and the portion between the 

 stigma and the ovary is called the style. Around the pistil stand 

 the stamens ; the upper part, divided into two lobes, is called 

 the anther, and from the anther proceeds a fine yeUow powder, 

 called the poUen. The seed is formed in the ovary only when 

 the pollen fertilizes the germ. Should this fertilization not take 

 place, the germs that are in the seed vessel never become devel- 

 oped into seeds, but perish. At Fig. 38 the reader will see a 

 single grain of poUen highly magnified, and will notice that it is 

 not very unlike a tadpole in appearance, only that the part which 

 corresponds to the tail of the tadpole is, in the poUen-grain, a little 

 rootlet. This pollen-grain falling on the stigma, throws out its 

 little rootlet, which runs down into and through the entire length 

 of -the style, as wiU. be seen by examining Fig. 39. On reaching 



