﻿Cultivated 
  Elementary 
  Species 
  91 
  

  

  the 
  real 
  systematic 
  units 
  in 
  elementary 
  species 
  

   play 
  the 
  same 
  part 
  as 
  in 
  ordinary 
  wild 
  species. 
  

   The 
  inference 
  that 
  the 
  origin 
  of 
  the 
  cultivated 
  

   plants 
  is 
  multiple, 
  in 
  most 
  cases, 
  and 
  that 
  more 
  

   than 
  one, 
  often 
  many 
  separate 
  elementary 
  

   forms 
  of 
  the 
  same 
  species 
  must 
  originally 
  have 
  

   been 
  taken 
  into 
  cultivation, 
  throws 
  much 
  light 
  

   upon 
  many 
  highly 
  important 
  problems 
  of 
  culti- 
  

   vation 
  and 
  selection. 
  This 
  aspect 
  of 
  the 
  ques- 
  

   tion 
  will 
  therefore 
  be 
  the 
  subject 
  of 
  the 
  next 
  

   lecture. 
  

  

  