﻿620 
  Mutations 
  

  

  dental 
  transference 
  of 
  new 
  qualities 
  into 
  the 
  

   already 
  existing 
  varieties 
  by 
  cross-pollination 
  

   through 
  the 
  agency 
  of 
  insects. 
  Instead 
  of 
  giv- 
  

   ing 
  long 
  lists 
  of 
  these 
  novelties, 
  I 
  may 
  cite 
  the 
  

   black 
  tulips, 
  which 
  cost 
  during 
  the 
  first 
  few 
  

   years 
  of 
  their 
  introduction 
  about 
  $25.00 
  apiece. 
  

  

  Horticultural 
  mutations 
  are 
  as 
  a 
  rule 
  very 
  

   rare, 
  especially 
  in 
  genera 
  or 
  species 
  which 
  have 
  

   not 
  yet 
  been 
  brought 
  to 
  a 
  high 
  degree 
  of 
  varia- 
  

   bility. 
  In 
  these 
  the 
  wide 
  range 
  of 
  varieties 
  and 
  

   the 
  large 
  scale 
  in 
  which 
  they 
  are 
  multiplied 
  of 
  

   course 
  give 
  a 
  greater 
  chance 
  for 
  new 
  varieties. 
  

   But 
  then 
  the 
  possibilities 
  of 
  crossing 
  are 
  like- 
  

   wise 
  much 
  larger, 
  and 
  apparent 
  changes 
  due 
  to 
  

   this 
  cause 
  may 
  easily 
  be 
  taken 
  for 
  original 
  mu- 
  

   tations. 
  

  

  The 
  rarity 
  of 
  the 
  mutations 
  is 
  often 
  proved 
  

   by 
  the 
  lapse 
  of 
  time 
  between 
  the 
  introduction 
  

   of 
  a 
  species 
  and 
  its 
  first 
  sport. 
  Some 
  instances 
  

   may 
  be 
  given. 
  They 
  afford 
  a 
  proof 
  of 
  the 
  length 
  

   of 
  the 
  period 
  during 
  which 
  the 
  species 
  remained 
  

   unaltered, 
  although 
  some 
  of 
  these 
  alterations 
  

   may 
  be 
  due 
  to 
  a 
  cross 
  with 
  an 
  allied 
  form. 
  

   Erytlirina 
  Crista-galli 
  was 
  introduced 
  about 
  

   1770, 
  and 
  produced 
  its 
  first 
  sport 
  in 
  1884, 
  after 
  

   more 
  than 
  a 
  century 
  of 
  cultivation. 
  Begonia 
  

   semperflorens 
  has 
  been 
  cultivated 
  since 
  1829, 
  

   and 
  for 
  half 
  a 
  century 
  before 
  it 
  commenced 
  

   sporting. 
  The 
  same 
  length 
  of 
  time 
  has 
  elapsed 
  

  

  