﻿ANIMAL 
  BEHAVIOUR 
  189 
  

  

  or 
  Aiptasia 
  will 
  refuse 
  to 
  take 
  bits 
  of 
  filter 
  paper, 
  though 
  

   it 
  will 
  still 
  take 
  meat. 
  " 
  After 
  it 
  has 
  thus 
  refused 
  paper, 
  

   two 
  or 
  three 
  pieces 
  of 
  meat 
  are 
  given 
  in 
  succession, 
  and 
  

   taken 
  readily. 
  Now 
  the 
  bit 
  of 
  paper 
  is 
  placed 
  again 
  on 
  the 
  

   disc, 
  and 
  it 
  too 
  is 
  swallowed. 
  Clearly, 
  the 
  uninterrupted 
  

   taking 
  of 
  a 
  number 
  of 
  pieces 
  of 
  meat 
  changes 
  the 
  physiologi- 
  

   cal 
  condition 
  in 
  some 
  way, 
  preparing 
  the 
  animal 
  for 
  the 
  

   taking 
  of 
  any 
  object 
  with 
  which 
  it 
  comes 
  in 
  contact. 
  One 
  

   cannot 
  fail 
  to 
  note 
  the 
  parallelism 
  with 
  what 
  occurs 
  in 
  higher 
  

   animals 
  under 
  similar 
  conditions 
  '' 
  (Jennings, 
  1906, 
  p. 
  226). 
  

   We 
  see, 
  then, 
  that 
  in 
  relatively 
  simple 
  creatures, 
  such 
  as 
  

   sea-anemones 
  and 
  starfishes, 
  which 
  have 
  no 
  nerve-ganglia, 
  

   past 
  stimuli 
  and 
  past 
  reactions 
  are 
  important 
  factors 
  in 
  

   determining 
  present 
  behaviour. 
  Thus 
  an 
  elongated 
  sea- 
  

   anemone, 
  Aiptasia 
  annulata, 
  which 
  lives 
  in 
  crevices 
  beneath 
  

   and 
  between 
  stones, 
  will 
  bend 
  into 
  a 
  new 
  position 
  if 
  it 
  

   is 
  touched 
  too 
  often, 
  and 
  if 
  it 
  be 
  molested 
  still 
  further 
  

   will 
  release 
  its 
  foothold 
  and 
  move 
  to 
  a 
  new 
  region 
  (p. 
  206). 
  

   In 
  its 
  natural 
  surroundings 
  it 
  often 
  has 
  to 
  cramp 
  its 
  

   body 
  into 
  quaint 
  zigzag 
  shapes, 
  and 
  a 
  point 
  of 
  some 
  

   interest 
  is 
  that 
  this 
  may 
  become 
  habitual 
  and 
  may 
  per- 
  

   sist 
  for 
  some 
  time 
  after 
  the 
  creature 
  is 
  removed 
  to 
  an 
  

   unimpeded 
  habitat. 
  This 
  illustrates 
  what 
  is 
  meant 
  by 
  

   registration. 
  

  

  In 
  his 
  valuable 
  study 
  of 
  the 
  behaviour 
  of 
  the 
  earthworm, 
  

   Prof. 
  H. 
  S. 
  Jennings 
  shows 
  that 
  the 
  response 
  to 
  a 
  stimulus 
  

   depends 
  on 
  external 
  factors 
  (such 
  as 
  the 
  intensity 
  and 
  locali- 
  

   sation 
  of 
  the 
  stimulus), 
  and 
  on 
  internal 
  factors 
  (such 
  as 
  

   the 
  state 
  of 
  the 
  animal 
  at 
  the 
  time, 
  its 
  tendency 
  to 
  move 
  

   in 
  a 
  certain 
  way, 
  e.g., 
  head 
  foremost, 
  and 
  the 
  direction 
  in 
  

   which 
  it 
  was 
  crawling 
  at 
  the 
  time). 
  But 
  what 
  is 
  particu- 
  

   larly 
  interesting 
  is 
  the 
  definite 
  evidence 
  that 
  the 
  behaviour 
  

  

  