Vlll PREFACE. 



been aided by B. M. Watson, to whose efficient aid 

 the first edition owed so much, and by my associate, 

 E. G. Lodeman. 



The chapter upon pollination has been omitted in 

 this edition, because a similar one has been incorpor- 

 ated in my "Plant-Breeding." The ordinal index, which 

 was a separate feature of the other editions, is now 

 included in the regular index. 



L. H. BAILEY. 

 CORNELL UNIVERSITY, 



ITHACA, N. Y., July i, 1896. 



