﻿MONGBELISATION 
  IN 
  LEPIDOPTERA. 
  48 
  

  

  of 
  the 
  reason 
  why 
  it 
  is 
  so 
  easy 
  to 
  breed 
  out 
  the 
  little 
  omicron 
  in 
  the 
  

   centre 
  of 
  each 
  wing 
  of 
  Zonosvma 
  annnlata, 
  nor 
  can 
  we 
  hazard 
  a 
  guess 
  

   as 
  to 
  whether 
  the 
  abs. 
  obsoleta 
  and 
  biobsoleta 
  are 
  atavic 
  forms, 
  or 
  

   developments 
  due 
  to 
  recent 
  changes 
  in 
  the 
  haunts 
  where 
  they 
  occur. 
  

   Workers 
  in 
  this 
  branch 
  of 
  study 
  must 
  not 
  overlook 
  the 
  secondary 
  

   bearings 
  of 
  the 
  experiments 
  of 
  Riding 
  and 
  Bacot 
  when 
  using 
  Tephrosia 
  

   crepuscularia 
  ab. 
  delamerensis 
  as 
  one 
  of 
  the 
  forms 
  of 
  the 
  species 
  experi- 
  

   mented 
  on, 
  for 
  their 
  hybrid 
  experiments 
  between 
  T. 
  crepuscularia 
  and 
  

   T. 
  bistortata. 
  Reference 
  can 
  be 
  readily 
  made 
  to 
  the 
  details 
  (Trans. 
  

   Ent. 
  Soc. 
  Loncl., 
  1898, 
  pp. 
  17-42). 
  The 
  influence 
  of 
  the 
  aberrational 
  

   form, 
  when 
  used 
  instead 
  of 
  the 
  typical 
  form 
  as 
  one 
  of 
  the 
  parents, 
  on 
  

   the 
  progeny, 
  was 
  most 
  marked.. 
  

  

  It 
  must 
  be 
  conceded, 
  that 
  there 
  may 
  sometimes 
  be 
  considerable 
  

   scientific 
  value 
  in 
  knowing 
  the 
  results 
  of 
  crossing 
  a 
  well-marked 
  

   aberration 
  with 
  its 
  typical 
  form, 
  yet 
  it 
  must 
  not 
  be 
  overlooked 
  that 
  it 
  

   is 
  still 
  more 
  important 
  to 
  discover 
  how 
  far 
  the 
  characters 
  that 
  come 
  to 
  

   the 
  front 
  in 
  an 
  aberration 
  are 
  capable 
  of 
  being 
  made 
  permanent 
  by 
  

   selection, 
  and 
  also 
  what 
  are 
  the 
  natural 
  conditions 
  of 
  environment 
  

   that 
  repress 
  these 
  latent 
  characters, 
  so 
  that 
  they 
  are 
  only 
  occasionally 
  

   exhibited 
  in 
  any 
  brood 
  bred 
  under 
  quite 
  natural 
  conditions. 
  Many 
  

   data 
  in 
  this 
  direction 
  are 
  no 
  doubt 
  available, 
  but 
  they 
  are 
  difficult 
  to 
  

   discover, 
  and 
  often 
  too 
  "incomplete 
  to 
  be 
  of 
  real 
  value. 
  Exact 
  data 
  

   bearing 
  on 
  this 
  view 
  of 
  the 
  question 
  are 
  much 
  w 
  Y 
  anted. 
  

  

  As 
  an 
  illustration 
  of 
  the 
  nature 
  of 
  the 
  so-called 
  " 
  dominant 
  " 
  and 
  

   " 
  recessive 
  " 
  elements 
  that 
  appear 
  and 
  disappear 
  in 
  the 
  progeny 
  

   resulting 
  from 
  the 
  crossing 
  of 
  a 
  type 
  and 
  a 
  well-marked 
  colour, 
  or 
  

   structural, 
  aberration, 
  we 
  may 
  call 
  attention 
  to 
  Raynor's 
  account 
  of 
  

   the 
  breeding 
  of 
  the 
  Jiavofasc 
  lata 
  (lacticolor) 
  form 
  of 
  Abraxas 
  grossidariata 
  

   (Ent. 
  Rec, 
  xiv., 
  pp. 
  321 
  et 
  seq.;.xv., 
  pp. 
  8 
  et 
  seq.). 
  In 
  these 
  experiments, 
  

   a 
  first 
  crossing 
  of 
  grossidariata 
  3 
  X 
  fiavofasc 
  lata 
  £ 
  produced 
  only 
  

   grossidariata, 
  whilst 
  inbred 
  grossulariata 
  of 
  this 
  strain, 
  i.e., 
  with 
  flavo- 
  

   fasciata 
  latent 
  in 
  them, 
  produced 
  several 
  flavofasciata 
  ? 
  s. 
  These 
  flavo- 
  

   fasciata 
  £ 
  s, 
  again 
  crossed 
  with 
  outside 
  $ 
  grossidariata, 
  produced 
  no 
  

   flavofasciata, 
  etc. 
  Doncaster, 
  who 
  has 
  made 
  an 
  attempt 
  to 
  explain 
  

   Raynor's 
  results, 
  on 
  the 
  basis 
  of 
  Mendel's 
  "law 
  of 
  heredity, 
  " 
  observes 
  

   (Ent. 
  Rec, 
  xv., 
  pp. 
  142 
  et 
  seq.) 
  that 
  it 
  may 
  seem 
  remarkable 
  that 
  

   among 
  the 
  children 
  of 
  & 
  flavofasciata 
  there 
  should 
  be 
  none 
  resembling 
  

   their 
  mother, 
  but 
  that 
  the 
  aberration 
  should 
  appear 
  again 
  in 
  some 
  

   abundance 
  in 
  the 
  grandchildren, 
  but 
  the 
  results 
  are 
  so 
  exactly 
  in 
  

   accord 
  with 
  what 
  would 
  be 
  expected 
  according 
  to 
  the 
  Mendelian 
  law 
  

   of 
  heredity, 
  that 
  it 
  has 
  seemed 
  worth 
  while 
  to 
  draw 
  attention 
  to 
  

   the 
  facts. 
  In 
  a 
  simple 
  Mendelian 
  case 
  when 
  two 
  varieties 
  — 
  in 
  this 
  

   instance 
  grossulariata 
  and 
  flavofasciata 
  — 
  are 
  bred 
  together, 
  their 
  

   offspring 
  all 
  resemble 
  one 
  of 
  the 
  parents, 
  and 
  the 
  character 
  of 
  that 
  

   parent 
  is 
  said 
  to 
  be 
  "dominant," 
  while 
  the 
  character 
  of 
  the 
  other 
  

   parent, 
  which 
  disappears 
  in 
  the 
  first 
  generation 
  of 
  offspring, 
  is 
  called 
  

   " 
  recessive." 
  But, 
  although 
  the 
  recessive 
  character 
  disappears, 
  it 
  is 
  

   latent, 
  and 
  the 
  hybrid 
  offspring 
  produces 
  germ-cells 
  hearing 
  either 
  the 
  

   dominant 
  character 
  or 
  the 
  recessive, 
  but 
  Dot 
  both 
  characters, 
  in 
  the 
  

   same 
  germ-cell. 
  If, 
  now, 
  equal 
  numbers 
  o( 
  dominant 
  (yrossulaHata) 
  

   and 
  recessive 
  (flavofasciata) 
  germ-cells 
  are 
  produced 
  by 
  each 
  hybrid, 
  

   and 
  these 
  meet 
  one 
  another 
  in 
  fertilisation 
  quite 
  by 
  chance, 
  then, 
  

   according 
  to 
  the 
  law 
  of 
  probability, 
  the 
  insects 
  o( 
  the 
  second 
  generation 
  

  

  