﻿dimorphism 
  and 
  polymorphism. 
  601 
  

  

  forms 
  is 
  that 
  they 
  fly 
  in 
  some 
  locahties 
  side 
  by 
  side, 
  

   which, 
  as 
  we 
  know, 
  he 
  does 
  not 
  admit 
  for 
  forms 
  of 
  the 
  

   same 
  species. 
  Then, 
  after 
  giving 
  some 
  details 
  of 
  lesser 
  

   importance, 
  by 
  which 
  Euryj)ihis 
  is 
  to 
  be 
  distinguished 
  

   from 
  Zephyrus, 
  such 
  as 
  a 
  darker 
  brown 
  under 
  side 
  of 
  the 
  

   wings 
  of 
  the 
  first, 
  as 
  compared 
  with 
  the 
  greyish 
  under 
  

   side 
  of 
  the 
  wings 
  of 
  the 
  second, 
  &c.. 
  Dr. 
  Staudinger 
  

   acknowledges 
  "that 
  some 
  of 
  the 
  females 
  of 
  Eurypihis 
  

   and 
  Zephyrus 
  are 
  not 
  to 
  be 
  separated 
  with 
  certainty," 
  

   and 
  this 
  statement 
  of 
  his 
  is 
  absolutely 
  fatal 
  to 
  the 
  cause 
  

   he 
  defends. 
  

  

  I 
  think 
  that 
  I 
  know 
  of 
  several 
  other 
  analogous 
  cases 
  

   in 
  the 
  same 
  genus, 
  but 
  I 
  do 
  not 
  think 
  it 
  prudent 
  to 
  

   speak 
  of 
  these 
  before 
  having 
  studied 
  them 
  more 
  

   thoroughly, 
  as 
  it 
  is 
  very 
  easy 
  to 
  fall 
  into 
  grave 
  errors 
  

   in 
  questions 
  of 
  so 
  delicate 
  a 
  nature; 
  and 
  I 
  will 
  now 
  

   pass 
  to 
  the 
  following 
  instance, 
  which 
  I 
  have 
  closely 
  

   analysed, 
  and 
  in 
  the 
  truth 
  of 
  which 
  I 
  have 
  no 
  reason 
  to 
  

   doubt. 
  

  

  Those 
  of 
  my 
  readers 
  who 
  may 
  find 
  interest 
  in 
  cases 
  

   of 
  dimorphism 
  presented 
  by 
  some 
  of 
  our 
  Palsearctic 
  

   Ehopalocera 
  are 
  surely 
  well 
  enough 
  acquainted 
  with 
  the 
  

   Lycfsnce, 
  — 
  Admetus, 
  Esp., 
  Ripartii, 
  Frr., 
  Dolus, 
  Hb., 
  and 
  

   Menalcas, 
  Frr., 
  — 
  so 
  that 
  it 
  is 
  useless 
  my 
  recapitulating 
  

   here 
  the 
  well-known 
  differences 
  which 
  characterise 
  these 
  

   four 
  forms. 
  It 
  is 
  sufficient 
  to 
  remark 
  that 
  nearly 
  all 
  

   lepidopterists 
  consider 
  L. 
  Ripartii 
  as 
  a 
  mere 
  variety 
  of 
  

   L. 
  Admetus, 
  and 
  that 
  L. 
  Menalcas 
  is 
  considered 
  as 
  the 
  

   Asia 
  Minor 
  form 
  of 
  L. 
  Dolus 
  of 
  France 
  and 
  Piedmont. 
  

   A 
  good 
  description 
  of 
  L. 
  Dolus, 
  Hb., 
  under 
  the 
  name 
  

   Lefehvrei, 
  is 
  given 
  by 
  Godart 
  in 
  his 
  ' 
  Encyclopedia 
  

   Methodique,' 
  p. 
  695 
  (1819), 
  but, 
  as 
  far 
  as 
  I 
  know, 
  

   Boisduval 
  is 
  the 
  first 
  who 
  points 
  out 
  the 
  affinities 
  of 
  

   Dolus, 
  Admetus, 
  and 
  Pdpartii. 
  In 
  his 
  * 
  Icones 
  His- 
  

   toriques,' 
  p. 
  71, 
  he 
  says, 
  speaking 
  of 
  Dolus: 
  — 
  " 
  Cette 
  

   espece 
  forme 
  avec 
  Admetus 
  et 
  Rippartii, 
  un 
  petit 
  groupe 
  

   fort 
  remarquable 
  par 
  le 
  duvet 
  cotonneux, 
  qui 
  couvre 
  une 
  

   partie 
  des 
  ailes 
  superieures 
  des 
  males. 
  On 
  ne 
  rencontre 
  

   cette 
  particularite 
  dans 
  aucune 
  autre 
  espece 
  connue." 
  

   Freyer, 
  in 
  describing 
  the 
  L. 
  Menalcas, 
  is 
  right 
  when 
  he 
  

   believes 
  it 
  to 
  be 
  a 
  variety 
  of 
  Dolus, 
  Hb. 
  

  

  Dr. 
  Staudinger, 
  who, 
  in 
  the 
  'Horse 
  Soc. 
  Ent. 
  Eoss.,' 
  

   vol. 
  xiv., 
  p. 
  248, 
  speaks 
  of 
  Menalcas 
  and 
  Ripartii, 
  says 
  

   that 
  he 
  fails 
  to 
  distinguish 
  the 
  females 
  of 
  these 
  two 
  

  

  