﻿Origin 
  of 
  Wild 
  Species 
  579 
  

  

  been 
  met 
  with. 
  Even 
  in 
  this 
  case 
  only 
  some- 
  

   thing 
  would 
  be 
  discovered 
  about 
  the 
  time 
  of 
  the 
  

   change, 
  but 
  nothing 
  about 
  its 
  real 
  nature. 
  

  

  So 
  it 
  is 
  in 
  many 
  cases. 
  If 
  a 
  variety 
  is 
  ob- 
  

   served 
  in 
  a 
  number 
  of 
  specimens 
  at 
  the 
  time 
  

   of 
  its 
  first 
  discovery, 
  and 
  at 
  a 
  locality 
  not 
  

   studied 
  previously, 
  it 
  takes 
  the 
  aspect 
  of 
  an 
  old 
  

   form 
  of 
  limited 
  distribution, 
  and 
  little 
  can 
  be 
  

   learned 
  as 
  to 
  the 
  circumstances 
  under 
  which 
  it 
  

   arose. 
  If 
  on 
  the 
  contrary 
  it 
  occurs 
  in 
  very 
  

   small 
  numbers 
  or 
  perhaps 
  even 
  in 
  a 
  single 
  in- 
  

   dividual, 
  and 
  if 
  the 
  spot 
  where 
  it 
  is 
  found 
  is 
  

   located 
  so 
  that 
  it 
  could 
  hardly 
  have 
  escaped 
  pre- 
  

   vious 
  observation, 
  then 
  the 
  presumption 
  of 
  a 
  re- 
  

   cent 
  origin 
  seems 
  justified. 
  

  

  What 
  has 
  to 
  be 
  ascertained 
  on 
  such 
  occasions 
  

   to 
  give 
  them 
  scientific 
  value? 
  Three 
  points 
  

   strike 
  me 
  as 
  being 
  of 
  the 
  highest 
  importance. 
  

   First, 
  the 
  constancy 
  of 
  the 
  new 
  type; 
  secondly, 
  

   the 
  occurrence 
  or 
  lack 
  of 
  intermediates, 
  and 
  last, 
  

   but 
  not 
  least, 
  the 
  direct 
  observation 
  of 
  a 
  re- 
  

   peated 
  production. 
  

  

  The 
  first 
  two 
  points 
  are 
  easily 
  ascertained. 
  

   Whether 
  the 
  new 
  type 
  is 
  linked 
  with 
  its 
  more 
  

   common 
  supposed 
  ancestor 
  by 
  intermediate 
  

   steps 
  is 
  a 
  query 
  which 
  at 
  once 
  strikes 
  the 
  bota- 
  

   nist. 
  It 
  is 
  usually 
  recorded 
  in 
  such 
  cases, 
  and 
  

   we 
  may 
  state 
  at 
  once 
  that 
  the 
  general 
  result 
  is, 
  

   that 
  such 
  intermediates 
  do 
  not 
  occur. 
  This 
  is 
  

  

  