﻿M0NGKELISATI0N 
  IN 
  LEPIDOPTERA. 
  49 
  

  

  character 
  of 
  the 
  aberration, 
  e.g., 
  to 
  illustrate 
  this 
  point, 
  Standfuss 
  

   observes 
  that 
  between 
  the 
  aberration 
  intermedia 
  of 
  Spilosoma 
  lubricipeda 
  

   and 
  the 
  darkest 
  of 
  its 
  aberrations, 
  deschangei, 
  there 
  are 
  many 
  degrees 
  

   leading 
  from 
  one 
  to 
  the 
  other, 
  but 
  that 
  no 
  transitional 
  forms 
  occur 
  to 
  

   bridge 
  over 
  the 
  wide 
  gap 
  between 
  intermedia 
  and 
  lubricipeda, 
  nor 
  can 
  

   they 
  be 
  produced 
  by 
  crossing 
  these 
  two. 
  " 
  It 
  seems," 
  Standfuss 
  says, 
  

   " 
  as 
  if 
  there 
  were 
  antagonistic 
  characters 
  which 
  cannot 
  exist 
  in 
  the 
  

   same 
  individual." 
  When 
  one 
  turns 
  to 
  Standfuss' 
  figures 
  (op. 
  cit., 
  pi. 
  

   viii., 
  figs. 
  11, 
  12, 
  13, 
  14), 
  one 
  finds 
  that 
  his 
  fig. 
  12 
  is 
  an 
  intermedia 
  

   really 
  fairly 
  close 
  to 
  lubricipeda, 
  between 
  which, 
  however, 
  we 
  ourselves 
  

   have 
  many 
  examples 
  bred 
  with 
  broods 
  that 
  have 
  given 
  progeny 
  

   extending 
  from 
  the 
  palest 
  typical 
  forms 
  to 
  the 
  darkest 
  deschangei. 
  We 
  

   are, 
  therefore, 
  in 
  want 
  here 
  of 
  a 
  distinct 
  definition 
  from 
  Standfuss 
  as 
  

   to 
  what 
  he 
  considers 
  an 
  intermediate. 
  The 
  statement 
  that 
  inter- 
  

   mediates 
  are 
  not 
  to 
  be 
  produced 
  in 
  the 
  manner 
  described 
  by 
  crossing 
  

   these 
  forms 
  is 
  entirely 
  contrary 
  to 
  fact. 
  

  

  What 
  one 
  desires, 
  in 
  estimating 
  the 
  value 
  of 
  results 
  in 
  the 
  direction 
  

   of 
  crossing 
  aberrations 
  with 
  the 
  parent 
  form, 
  is, 
  as 
  we 
  have 
  already 
  

   indicated, 
  a 
  clear 
  idea 
  of 
  the 
  value 
  of 
  the 
  aberration 
  used. 
  It 
  is 
  quite 
  

   certain 
  that 
  there 
  will 
  be 
  considerable 
  difference 
  in 
  the 
  results 
  obtained 
  

   if 
  we 
  use 
  for 
  such 
  experiments 
  as 
  are 
  here 
  indicated 
  — 
  (1) 
  an 
  individual 
  

   which 
  is 
  a 
  chance 
  sport 
  occasionally 
  (or 
  frequently) 
  appearing 
  in 
  

   nature, 
  but 
  with 
  no 
  capability 
  of 
  becoming 
  a 
  fixed 
  race 
  under 
  its 
  

   natural 
  conditions 
  of 
  environment, 
  or 
  (2) 
  one 
  of 
  a 
  selected 
  race, 
  

   produced 
  and 
  maintained 
  as 
  such 
  under 
  artificial 
  conditions 
  of 
  en- 
  

   vironment 
  through 
  many 
  generations, 
  and 
  inbred 
  until 
  it 
  has 
  all 
  the 
  

   characters 
  of 
  a 
  local 
  race 
  rather 
  than 
  an 
  aberration. 
  

  

  This 
  point 
  is 
  well 
  illustrated 
  in 
  Spilosoma 
  lubricipeda 
  ab. 
  zatima. 
  

   In 
  Heligoland, 
  and 
  on 
  the 
  northeast 
  coast 
  of 
  England, 
  occasional 
  

   extreme, 
  and 
  other 
  less 
  marked, 
  aberrations 
  of 
  8. 
  lubricipeda 
  have 
  

   occurred 
  for 
  more 
  than 
  a 
  century 
  (Cramer, 
  1782 
  ; 
  Haworth, 
  1812 
  ; 
  

   Wood, 
  1839, 
  etc.), 
  but 
  the 
  total 
  number 
  taken 
  in 
  Britain, 
  for 
  at 
  least 
  

   a 
  century, 
  appears 
  to 
  have 
  been 
  fewer 
  than 
  a 
  dozen, 
  and 
  evidence 
  as 
  to 
  

   any 
  greater 
  regularity 
  of 
  its 
  occurrence 
  in 
  Heligoland 
  and 
  Holland, 
  

   other 
  than 
  as 
  an 
  almost 
  equally 
  rare 
  sporadic 
  aberration, 
  appears 
  to 
  be 
  

   wanting. 
  Gatke, 
  in 
  1882, 
  had 
  numerous 
  examples 
  bred 
  in 
  Heligoland, 
  

   including 
  intermediates 
  between 
  zatima 
  and 
  the 
  type 
  (see 
  Entom., 
  

   xxviii., 
  pp. 
  6-7). 
  In 
  Britain, 
  up 
  to 
  that 
  time, 
  it 
  had 
  never 
  occurred 
  

   except 
  as 
  a 
  purely 
  sporadic 
  and 
  very 
  rare 
  aberration. 
  From 
  the 
  

   Heligoland 
  stock, 
  a 
  French 
  lepidopterist 
  (and 
  dealer), 
  named 
  Deschange 
  

   appears 
  to 
  have 
  interbred 
  extreme 
  and 
  intermediate 
  forms 
  for 
  many 
  

   years, 
  advertising 
  the 
  imagines 
  and 
  pupae 
  for 
  sale 
  in 
  the 
  continental 
  

   magazines, 
  whilst, 
  in 
  1886, 
  Depuiset 
  described 
  and 
  figured 
  the 
  then 
  

   most 
  extreme 
  form 
  known 
  as 
  deschangei 
  (Ann. 
  Soc. 
  Ent. 
  France, 
  1886, 
  pL 
  

   iv., 
  fig. 
  4). 
  In 
  1889 
  and 
  1890, 
  imagines 
  were 
  on 
  sale 
  in 
  Britain, 
  and 
  in 
  

   1889, 
  Clark 
  exhibited 
  examples, 
  so 
  bought 
  (Ent. 
  /iV<\, 
  L, 
  p. 
  71), 
  [ 
  n 
  

   1891, 
  Harrison 
  advertised 
  for 
  pupa 
  4 
  of 
  lubricipeda, 
  and, 
  later, 
  bred 
  a 
  9 
  

   zatima 
  from 
  a 
  pupa, 
  supposed 
  to 
  have 
  come 
  from 
  London 
  through 
  

   Riches 
  (Ent, 
  xxvi., 
  p. 
  346). 
  Riches 
  considered 
  this 
  a 
  mistake, 
  

   asserting 
  that 
  he 
  had 
  never 
  bred 
  the 
  form, 
  and 
  that 
  it 
  was 
  quite 
  

   unknown 
  as 
  a 
  local 
  form 
  to 
  London 
  lepidopterists 
  ^<>/». 
  cit.. 
  \\ 
  

   847), 
  and 
  he 
  further 
  informed 
  us 
  thai 
  South's 
  description 
  of 
  the 
  9 
  

   bred 
  (op. 
  cit., 
  p. 
  846) 
  exactly 
  coincided 
  with 
  the 
  specimens 
  exhibited 
  

   by 
  Clark 
  in 
  1889. 
  Tugwell 
  transferred 
  (Ent., 
  xxvii., 
  \\ 
  971 
  the 
  

  

  