﻿ECHINO 
  DERM 
  ATA. 
  151 
  

  

  specimen 
  measurin2: 
  46 
  millira. 
  in 
  length 
  has 
  a 
  greatest 
  width 
  of 
  

   2i) 
  and 
  a 
  greatest 
  depth 
  of 
  15 
  millim. 
  The 
  dorsal 
  surface 
  slopes 
  

   graduallj- 
  to 
  the 
  two 
  sides, 
  which 
  are 
  marked 
  off 
  from 
  the 
  ventral 
  

   surface 
  by 
  the 
  development 
  along 
  the 
  lateral 
  line 
  of 
  from 
  three 
  to 
  six 
  

   short, 
  conical, 
  sharp 
  denticle-like 
  processes. 
  From 
  the 
  median 
  dorsal 
  

   line 
  to 
  this 
  line 
  the 
  scattered 
  suckers 
  increase 
  in 
  number 
  ; 
  they 
  are, 
  

   however, 
  much 
  more 
  numerous 
  on 
  the 
  ventral 
  surface, 
  and 
  more 
  re- 
  

   gularity 
  of 
  distribution 
  is 
  to 
  be 
  observed 
  along 
  the 
  ventral 
  median 
  line 
  

   than 
  in 
  any 
  other 
  part. 
  The 
  suckers 
  are 
  provided 
  with 
  stout 
  plates, 
  

   but 
  no 
  special 
  terminal 
  plate 
  was 
  detected. 
  The 
  calcareous 
  plates 
  in 
  

   the 
  skin 
  are 
  on 
  the 
  general 
  plan 
  of 
  those 
  in 
  S. 
  unisemita 
  ; 
  but 
  the 
  bars 
  

   do 
  not 
  appear 
  to 
  be 
  so 
  stout, 
  and 
  there 
  may 
  be 
  at 
  least 
  seven 
  pores. 
  

   The 
  ten 
  pieces 
  of 
  the 
  calcareous 
  ring 
  are 
  all 
  equal, 
  and 
  the 
  retractor 
  

   muscles 
  are 
  not 
  especially 
  strongly 
  developed. 
  As 
  in 
  ^S^. 
  unisemita 
  

   there 
  is, 
  comparatively, 
  a 
  feeble 
  development 
  of 
  the 
  digestive 
  and 
  

   respiratory 
  organs 
  ; 
  but 
  these 
  characters, 
  as 
  well 
  as 
  the 
  stiffness 
  of 
  

   the 
  tentacles, 
  are 
  rather 
  points 
  of 
  generic 
  importance. 
  

  

  A 
  more 
  complete 
  generic 
  diagnosis 
  will 
  be 
  made 
  when 
  the 
  two 
  

   species 
  have 
  been 
  carefully 
  compared. 
  

  

  Two 
  young 
  specimens 
  have 
  the 
  integument 
  much 
  thinner. 
  

  

  Port 
  Jackson, 
  0-5 
  fms., 
  where 
  it 
  is, 
  as 
  otlior 
  collections 
  show, 
  

   exceedingly 
  common. 
  Also 
  fi-om 
  North 
  Dunbar 
  Island, 
  China 
  seas, 
  

   and 
  from 
  between 
  Ball's 
  Head 
  and 
  Goat 
  Island 
  (coll. 
  Brazier) 
  ; 
  and 
  

   two 
  dried 
  specimens, 
  purchased 
  in 
  1848 
  of 
  Mr, 
  Cuming, 
  from 
  Bris- 
  

   bane 
  Water, 
  N. 
  S. 
  W. 
  

  

  In 
  the 
  definition 
  of 
  the 
  genus 
  given 
  by 
  Prof. 
  Selenka 
  there 
  occur 
  

   the 
  words 
  " 
  Korper 
  mit 
  einfachen 
  Fiisschen 
  bedeckt, 
  die 
  in 
  der 
  

   rechten 
  (oder 
  linken) 
  Flanke 
  in 
  einer 
  Doppelreihe 
  stehen 
  ; 
  " 
  and 
  

   the 
  presence 
  of 
  this 
  more 
  distinct 
  set 
  of 
  suckers 
  is 
  implied 
  in 
  the 
  

   specific 
  term 
  of 
  the 
  American 
  species, 
  unisemita. 
  In 
  the 
  present 
  

   species, 
  of 
  which 
  there 
  is 
  a 
  good 
  supply 
  of 
  specimens, 
  I 
  observe 
  that 
  

   the 
  double 
  row 
  occupies 
  the 
  middle 
  of 
  the 
  trivium, 
  but 
  that 
  it 
  

   varies 
  considerably 
  in 
  the 
  extent 
  to 
  which 
  it 
  is 
  distinctlj^ 
  developed. 
  

   Some 
  modification 
  of 
  the 
  generic 
  diagnosis 
  must 
  therefore 
  lie 
  made, 
  

   and 
  the 
  suckers 
  be 
  spoken 
  of 
  as 
  scattered 
  over 
  the 
  body, 
  but 
  having 
  

   a 
  tendency 
  to 
  form 
  a 
  regular 
  double 
  row 
  in 
  some 
  part 
  of 
  the 
  

   trivium 
  *. 
  

  

  15. 
  Stichopus 
  variegatus. 
  

   Seirvper, 
  Hoi. 
  p. 
  73. 
  

   A 
  single, 
  rather 
  small 
  specimen 
  from 
  Port 
  Molle. 
  

  

  * 
  Since 
  working 
  out 
  this 
  species 
  I 
  have 
  had 
  the 
  opportunity 
  of 
  examining 
  

   another 
  member 
  of 
  the 
  genus 
  from 
  Kurrachee 
  ; 
  for 
  8. 
  murrayi 
  see 
  Proc. 
  Zool. 
  

   See. 
  1883, 
  p. 
  61. 
  

  

  Mr. 
  Ramsay 
  tells 
  me 
  that 
  the 
  naturalists 
  of 
  Sydney 
  have 
  been 
  in 
  tlio 
  habit 
  of 
  

   regarding 
  ^S. 
  validum 
  as 
  the 
  Holothuria 
  spinosa 
  of 
  Quoy 
  and 
  Gaimard 
  : 
  this 
  

   determination 
  cannot, 
  I 
  think, 
  be 
  accepted. 
  

  

  