Volume I By Chapters 



Foreword ............................. P a g e 3 



I How the Cactus Got Its Spines 

 And How It Lost Them 



A Sidelight on 7 



The Importance of Environment ..... , ....... * 



II Twenty-three Potato Seeds 

 And What They Taught 



A Glimpse at the o r 



Influence of Heredity .................. 3D 



III No Two Living Things 

 Exactly Alike 



Infinite Ingenuity the Price rjpj 



of Variation ......................... O i 



IV The Rivalry of Plants 

 To Please Us 



On the Forward March of 1 f\'~} 



Adaptation ......................... IU / 



V Let Us Now Produce a 

 New Pink Daisy 



A Practical Lesson in "1/11 



Harne88ing Heredity .................... 141 



VI Short-Cuts Into the 

 Centuries to Come 



Better Plants Secured by -i rjn 



Hurrying Evolution .................... 1 < * 



VII How Far Can Plant 

 Improvement Go ? 



The Crossroads Where Fact 



and Theory Seem to Part ................. 



VIII Some Plants Which Are Begging 

 for Immediate Improvement 



A Rough Survey of 

 the Possibilities 



IX Piecing the Fragments of a 

 Motion Picture Film 



We Stop to Take 

 A Backward Glance 



List of Direct Color Photograph Prints ..... 305 



34835G 



