﻿502 
  Cases 
  of 
  dimorphism 
  and 
  polymorphism. 
  

  

  TjijccBiice, 
  but, 
  in 
  the 
  same 
  pai^er, 
  speaking 
  of 
  Admetus 
  

   and 
  Ripartii, 
  he 
  expresses 
  a 
  certain 
  doubt 
  as 
  to 
  these 
  

   last 
  two 
  belonging 
  to 
  one 
  species. 
  

  

  Now 
  we 
  know 
  that, 
  in 
  reality, 
  the 
  last 
  two 
  forms 
  differ 
  

   only 
  in 
  Ripartii 
  having 
  a 
  distinct 
  white 
  streak 
  on 
  the 
  

   under 
  side 
  of 
  the 
  hind 
  posterior 
  wings, 
  which 
  is 
  deficient 
  

   in 
  Admetus. 
  

  

  Dr. 
  Staudinger 
  next 
  speaks 
  of 
  intermediate 
  forms, 
  

   found 
  in 
  Asia 
  Minor, 
  with 
  the 
  streak 
  partly 
  present. 
  

   Such 
  intermediate 
  forms 
  he 
  is 
  inclined 
  to 
  consider 
  as 
  

   hybrids 
  of 
  Admetus 
  and 
  Ripartii. 
  But 
  this 
  same 
  streak 
  

   is 
  so 
  variable 
  in 
  the 
  intricate 
  Lyccena 
  Damon, 
  Schiff., 
  

   group, 
  that 
  it 
  has 
  entirely 
  lost, 
  in 
  my 
  opinion, 
  any 
  

   importance 
  as 
  a 
  specific 
  character. 
  

  

  Having 
  lately 
  had 
  the 
  opportunity 
  of 
  closely 
  examining 
  

   specimens 
  of 
  Admetus, 
  Ripartii, 
  Dolas, 
  and 
  Menalca^, 
  

   having 
  done 
  it 
  with 
  the 
  greatest 
  care 
  and 
  with 
  the 
  aid 
  of 
  

   good 
  magnifying 
  glasses, 
  having 
  weighed 
  all 
  the 
  pros 
  

   and 
  the 
  cons 
  of 
  the 
  question, 
  I 
  now 
  firml}' 
  believe 
  that 
  

   all 
  four 
  forms 
  belong 
  to 
  one 
  species. 
  We 
  consequently 
  

   have, 
  in 
  France, 
  Dolus 
  and 
  Ripartii 
  as 
  dimorphic 
  forms 
  

   of 
  a 
  species 
  which, 
  in 
  Asia 
  Minor, 
  occurs 
  in 
  three 
  forms 
  

   — 
  Admetus, 
  Ripartii, 
  and 
  Menalcas. 
  The 
  whitish-blue 
  

   forms, 
  Dolus 
  and 
  Menalca^i, 
  are 
  found 
  nowhere 
  inde- 
  

   pendently 
  from 
  Ripartii; 
  whilst 
  the 
  latter 
  and 
  Adinetus 
  

   do 
  occur 
  in 
  certain 
  countries 
  as 
  constant 
  and 
  perfectly 
  

   monomorphic 
  forms. 
  

  

  I 
  firmly 
  believe 
  that 
  when 
  the 
  majority 
  of 
  similar 
  

   instances 
  of 
  dimorphism 
  or 
  polymorphism 
  have 
  been 
  

   recorded, 
  it 
  will 
  be 
  found 
  that 
  the 
  number 
  of 
  such 
  cases 
  

   in 
  the 
  male 
  sex 
  of 
  Palaearctic 
  Lepidoptera 
  is 
  by 
  no 
  

   means 
  inferior 
  to 
  the 
  number 
  of 
  cases 
  presented 
  by 
  the 
  

   female 
  sex. 
  

  

  