﻿CAMOUFLAGE 
  — 
  FRIEDMANN 
  269 
  

  

  sharp 
  ridges. 
  Convexities 
  may 
  be 
  made 
  to 
  appear 
  concave, 
  flat 
  surfaces 
  

   to 
  assume 
  undulations, 
  and 
  curved 
  areas 
  to 
  flatten 
  out, 
  by 
  the 
  relation 
  of 
  

   adjacent 
  pattern 
  elements. 
  The 
  consequent 
  distortion 
  of 
  the 
  true 
  

   shape 
  of 
  the 
  creature 
  into 
  the 
  resulting 
  optical 
  shape 
  helps 
  to 
  conceal 
  

   it 
  just 
  as 
  well 
  as 
  the 
  actual 
  disruptive 
  marks 
  tend 
  to 
  reduce 
  it 
  to 
  a 
  mass 
  

   of 
  unconnected 
  pieces. 
  It 
  is 
  a 
  curious 
  fact, 
  and 
  one 
  which 
  demon- 
  

   strates 
  the 
  enormous 
  range 
  of 
  form, 
  color, 
  and 
  pattern 
  to 
  be 
  observed 
  

   in 
  animal 
  coloration, 
  that 
  the 
  general 
  result 
  of 
  camouflaged 
  appear- 
  

   ance 
  can 
  be 
  arrived 
  at 
  by 
  such 
  diametrically 
  opposed 
  methods 
  as 
  oblit- 
  

   erative 
  shading 
  (which 
  reduces 
  or 
  dissolves 
  solid 
  form) 
  and 
  construc- 
  

   tive 
  shading 
  (which 
  builds 
  up 
  the 
  appearance 
  of 
  form 
  that 
  is 
  not 
  

   there 
  — 
  such 
  as 
  ridges, 
  convexities, 
  etc.) 
  . 
  It 
  may 
  be 
  well 
  to 
  state 
  again, 
  

   in 
  different 
  words, 
  this 
  matter 
  of 
  constructive 
  shading 
  and 
  disruptive 
  

   marks. 
  In 
  a 
  very 
  general 
  way 
  it 
  may 
  be 
  said 
  that 
  the 
  illusion 
  of 
  dis- 
  

   continuity 
  (the 
  result 
  of 
  disruptive 
  marks 
  in 
  their 
  simplest 
  form) 
  is 
  a 
  

   matter 
  of 
  color 
  contrast 
  on 
  a 
  fairly 
  even 
  surface, 
  while 
  constructive 
  

   shading 
  produces 
  the 
  illusion 
  of 
  surface 
  modeling. 
  A 
  combination 
  of 
  

   the 
  two 
  not 
  only 
  fragments 
  a 
  whole 
  into 
  optically 
  distinct 
  and 
  appar- 
  

   ently 
  unrelated 
  parts, 
  but 
  also 
  by 
  its 
  sculptural 
  illusion 
  renders 
  it 
  more 
  

   difficult 
  for 
  the 
  eye 
  to 
  conceive 
  these 
  pieces 
  as 
  being 
  in 
  the 
  same 
  plane 
  

   and 
  therefore 
  connectable. 
  In 
  some 
  instances, 
  constructive 
  shading 
  

   brings 
  about 
  an 
  astonishing 
  similarity 
  to 
  other 
  objects 
  such 
  as 
  the 
  

   appearance 
  of 
  leaf 
  vein 
  ridges 
  in 
  some 
  caterpillars. 
  

  

  Somewhat 
  akin 
  to 
  constructive 
  shading 
  in 
  its 
  power 
  of 
  optical 
  distor- 
  

   tion 
  is 
  another 
  type 
  of 
  disruptive 
  pattern 
  which 
  has 
  the 
  effect 
  of 
  seem- 
  

   ing 
  to 
  connect 
  wholly 
  distinct 
  and 
  not 
  even 
  adjacent 
  parts 
  of 
  the 
  body, 
  

   thus 
  further 
  confusing 
  the 
  eye 
  of 
  the 
  beholder 
  and 
  to 
  that 
  extent 
  help- 
  

   ing 
  to 
  hinder 
  or 
  delay 
  recognition 
  of 
  the 
  animal. 
  A 
  good 
  example 
  is 
  

   the 
  banded 
  pattern 
  in 
  many 
  frogs. 
  When 
  the 
  frog 
  is 
  at 
  rest 
  (and 
  in 
  

   most 
  cases 
  no 
  camouflage 
  is 
  of 
  use 
  when 
  the 
  creature 
  is 
  moving) 
  the 
  

   legs 
  are 
  folded 
  close 
  against 
  the 
  body 
  and 
  the 
  bands 
  of 
  the 
  body 
  ap- 
  

   pear 
  to 
  be 
  continuous 
  with 
  those 
  of 
  both 
  the 
  upper 
  and 
  the 
  lower 
  por- 
  

   tions 
  of 
  the 
  leg, 
  optically 
  merging 
  into 
  one 
  mass. 
  If 
  the 
  bands 
  went 
  

   in 
  different 
  directions 
  on 
  the 
  legs 
  they 
  would 
  stand 
  out 
  distinctly 
  from 
  

   the 
  body 
  and 
  attract 
  attention. 
  

  

  In 
  many 
  fishes 
  there 
  is 
  a 
  dark 
  diagonal 
  disruptive 
  band 
  on 
  the 
  body 
  

   which 
  often 
  extends 
  on 
  to 
  the 
  pectoral 
  or 
  the 
  pelvic 
  fins, 
  which, 
  if 
  not 
  

   so 
  connected 
  by 
  pattern 
  with 
  the 
  body 
  would 
  be 
  much 
  more 
  noticeable. 
  

   Many 
  insects 
  show 
  similar 
  patterns 
  involving 
  legs 
  or 
  antennae 
  as 
  well 
  

   as 
  portions 
  of 
  the 
  body. 
  This 
  type 
  of 
  color 
  pattern 
  has 
  been 
  termed 
  

   coincident 
  disruptive 
  pattern 
  by 
  Cott, 
  who 
  was 
  the 
  first 
  to 
  emphasize 
  

   the 
  continuity 
  of 
  patterns 
  of 
  the 
  head 
  across 
  the 
  eye 
  in 
  order 
  to 
  hide 
  the 
  

   eye 
  itself, 
  ordinarily 
  the 
  most 
  difficult 
  part 
  of 
  an 
  animal 
  to 
  conceal. 
  

  

  Many 
  fishes, 
  frogs, 
  snakes, 
  birds, 
  and 
  mammals 
  have 
  large 
  rounded 
  black 
  pupils 
  

   which 
  conform 
  to 
  this 
  very 
  shape 
  most 
  likely 
  to 
  catch 
  an 
  observer's 
  eye. 
  However 
  

  

  