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  hylim. 
  

  

  Geographical 
  Variations. 
  — 
  This 
  species 
  may 
  be 
  

   divided, 
  from 
  the 
  permanent 
  markings, 
  into 
  a 
  number 
  

   of 
  more 
  or 
  less 
  defined 
  varieties, 
  each 
  of 
  which 
  has 
  a 
  

   distinct 
  habitat. 
  

  

  1. 
  Forma 
  ti/pica. 
  A 
  greyish, 
  brown, 
  or 
  black 
  streak, 
  

   edged 
  above 
  with 
  yellow 
  or 
  white, 
  extends 
  from 
  the 
  

   nostril 
  through 
  the 
  eye 
  and 
  the 
  tympanum 
  along 
  the 
  

   side 
  of 
  the 
  body, 
  sending 
  upwards 
  and 
  forwards 
  a 
  

   branch 
  on 
  the 
  loin 
  ; 
  a 
  whitish 
  line 
  on 
  the 
  upper 
  lip, 
  

   descending 
  to 
  the 
  shoulder, 
  and 
  then 
  ascending 
  to 
  the 
  

   eye, 
  limiting 
  an 
  elongate 
  green 
  area 
  behind 
  and 
  below 
  

   the 
  commissure 
  of 
  the 
  jaws 
  ; 
  a 
  dark, 
  light-edged 
  cross- 
  

   line 
  above 
  the 
  vent 
  ; 
  the 
  outer 
  side 
  of 
  the 
  fore-arm, 
  

   carpus 
  and 
  fourth 
  finger, 
  tibia, 
  tarsus, 
  metatarsus, 
  

   and 
  fifth 
  toe 
  with 
  a 
  more 
  or 
  less 
  distinct 
  dark 
  and 
  

   light 
  edge. 
  

  

  This 
  is 
  the 
  most 
  widely 
  distributed 
  form 
  in 
  Europe, 
  

   inhabiting 
  the 
  greater 
  part 
  of 
  the 
  continent 
  and 
  ex- 
  

   tending 
  into 
  Asia 
  Minor. 
  

  

  2. 
  Var. 
  savignyi, 
  Aud. 
  (japonica, 
  Gthr.). 
  Similar 
  

   to 
  the 
  typical 
  form, 
  but 
  the 
  marking 
  on 
  the 
  loin 
  is 
  

   absent, 
  or 
  distinct 
  from 
  the 
  lateral 
  streak, 
  which 
  is 
  

   frequently 
  broken 
  up 
  into 
  spots 
  from 
  the 
  middle 
  of 
  

   the 
  side. 
  

  

  Inhabits 
  Corsica, 
  Elba, 
  Sardinia, 
  the 
  Greek 
  Archi- 
  

   pelago, 
  South-western 
  Asia, 
  Lower 
  Egypt, 
  Corea, 
  

   China, 
  and 
  Japan. 
  

  

  Allusion 
  has 
  been 
  made 
  in 
  the 
  Introduction 
  to 
  the 
  

   great 
  facility 
  with 
  which 
  the 
  common 
  tree-frog 
  not 
  

   only 
  changes 
  colour, 
  but 
  also 
  puts 
  on 
  temporary 
  dark 
  

   or 
  light 
  spots, 
  which 
  greatly 
  alter 
  its 
  appearance. 
  

   In 
  this 
  variety, 
  however, 
  we 
  find 
  specimens 
  with 
  large 
  

   dark 
  spots 
  or 
  stripes 
  on 
  the 
  back 
  and 
  cross-bars 
  on 
  

   the 
  limbs, 
  which 
  appear 
  to 
  be 
  permanent, 
  and 
  owing 
  

   to 
  which 
  these 
  frogs 
  have 
  been 
  regarded 
  as 
  distinct 
  

   species 
  (77. 
  japonica, 
  Gthr., 
  H. 
  sarda, 
  Bonelli). 
  Such 
  

   specimens 
  are 
  more 
  frequent 
  in 
  China 
  and 
  Japan, 
  

   but 
  also 
  occur, 
  though 
  in 
  lesser 
  abundance 
  than 
  and 
  

   promiscuously 
  with 
  unspotted 
  ones, 
  in 
  Corsica, 
  in 
  

  

  