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  ECHINODERMATA. 
  

  

  F. 
  JEFFllEY 
  BELL. 
  

  

  The 
  chief 
  points 
  of 
  interest 
  attached 
  to 
  the 
  ' 
  Alert 
  ' 
  collection 
  of 
  

   Echinoderms 
  may 
  be 
  indicated 
  as 
  follows 
  : 
  — 
  

  

  Though 
  there 
  are 
  no 
  new 
  Echinoidea, 
  there 
  are 
  some 
  very 
  pre- 
  

   cious 
  series 
  of 
  some 
  species, 
  Maretia 
  platwlata 
  being 
  notably 
  well 
  

   represented. 
  Similarly 
  the 
  series 
  of 
  some 
  of 
  the 
  Asterids 
  has 
  given 
  

   us 
  evidence 
  of 
  a 
  variability 
  that 
  would 
  be 
  almost 
  incredible 
  but 
  for 
  

   the 
  careful 
  registration 
  of 
  the 
  localities 
  of 
  the 
  species. 
  Eare 
  and 
  

   new 
  forms 
  of 
  Ophiurids 
  and 
  Asterids 
  will, 
  on 
  inspection 
  of 
  the 
  suc- 
  

   ceeding 
  systematic 
  list, 
  be 
  found 
  to 
  be 
  well 
  represented 
  : 
  OpMotlirix 
  

   has 
  a 
  large 
  number 
  of 
  forms, 
  the 
  exact 
  delimitation 
  and 
  definition 
  of 
  

   which 
  has 
  been 
  to 
  me 
  a 
  matter 
  of 
  just 
  as 
  much 
  anxiety 
  and 
  doubt 
  

   as 
  it 
  has 
  been 
  to 
  my 
  predecessors 
  ; 
  but 
  a 
  study 
  of 
  the 
  collection 
  has 
  

   led 
  me 
  to 
  a 
  somewhat 
  important 
  conclusion, 
  in 
  that 
  I 
  have 
  been 
  

   compelled 
  by 
  the 
  evidence 
  to 
  attach 
  much 
  less 
  weight 
  than 
  some 
  

   have 
  done 
  to 
  the 
  characters 
  of 
  the 
  coloration 
  *. 
  

  

  The 
  question 
  of 
  coloration 
  of 
  forms 
  has 
  taken 
  on 
  almost 
  a 
  new 
  

   aspect 
  since 
  the 
  publication 
  by 
  Mr. 
  Seebohm 
  of 
  his 
  views 
  as 
  to 
  the 
  

   value 
  of 
  the 
  pattern 
  of 
  colour 
  in 
  the 
  Turdinse 
  (Cat. 
  Birds 
  B.M. 
  v. 
  

   p. 
  viii) 
  ; 
  while, 
  on 
  the 
  other 
  hand, 
  the 
  recent 
  statements 
  of 
  such 
  ex- 
  

   perienced 
  entomologists 
  as 
  Butler, 
  who 
  thinks 
  that 
  in 
  time 
  it 
  will 
  

   be 
  impossible 
  to 
  decide, 
  without 
  rearing 
  from 
  the 
  egg, 
  whether 
  any 
  

   form 
  is 
  a 
  species, 
  a 
  hybrid, 
  or 
  a 
  variety 
  (Trans. 
  Ent. 
  Soc. 
  1880, 
  

   p. 
  200), 
  and 
  Elwes, 
  in 
  whose 
  opinion 
  {I. 
  c. 
  p. 
  134) 
  climate, 
  food, 
  and 
  

   conditions 
  of 
  life 
  will 
  more 
  than 
  account 
  for 
  the 
  change 
  in 
  tint 
  of 
  

   certain 
  representative 
  species, 
  seem 
  to 
  indicate 
  that 
  in 
  the 
  group 
  of 
  

   the 
  Lepidoptera, 
  where 
  coloration 
  has 
  been 
  so 
  much 
  attended 
  to, 
  

   those 
  who 
  are 
  among 
  the 
  most 
  experienced 
  are 
  learning 
  to 
  doubt 
  its 
  

   value, 
  and 
  to 
  recognize, 
  as 
  the 
  professed 
  students 
  of 
  ichthyology 
  

   (see 
  Giinther's 
  ' 
  Study 
  of 
  Fishes,' 
  pp. 
  176-182) 
  would 
  seem 
  to 
  have 
  

   done, 
  that 
  in 
  coloration 
  there 
  is 
  great 
  variation. 
  It 
  would 
  be 
  a 
  

   matter 
  for 
  regret 
  if, 
  when 
  the 
  views 
  of 
  others 
  are 
  advancing, 
  the 
  

   describer 
  and 
  systematist 
  of 
  Echinoderms 
  should 
  make 
  a 
  backward 
  

  

  * 
  Liitken, 
  "Le 
  systeme 
  general 
  de 
  coloration 
  constitue 
  un 
  caractere 
  impor- 
  

   tant 
  qu'il 
  ne 
  faut 
  pas 
  negliger 
  dans 
  la 
  distinction 
  des 
  Ophiothrix" 
  (Vid. 
  Selsfc 
  

   Skr. 
  (5) 
  Bd. 
  8, 
  ii. 
  p. 
  104) 
  ; 
  and 
  compare 
  the 
  descriptions 
  of 
  all 
  writers 
  on 
  the 
  

   genus. 
  

  

  