4 NATURE STUDY AND AGRICULTURE 
yield and the best possible quality, and may in that way 
gradually, though perhaps unconsciously, help to develop 
improved strains. Besides that, many specialists are de- 
voting their knowledge and skill to the difficult task of pro- 
ducing varieties that shall serve our needs more abundantly. 
It is perhaps needless to add that whatever may be our 
purpose in raising plants, — whether we want a good crop 
of corn or a fine display of flowers, or to develop more beau- 
tiful, more hardy, or more productive varieties, we must 
have a practical knowledge of the nature of plants and the 
laws of their growth. Not only is this knowledge of the 
utmost value, but the study of the subject is wonderfully 
interesting to every inquiring mind. 
