﻿ECHIN0DEE3IATA. 
  177 
  

  

  necting 
  or 
  southern 
  Australian 
  currents, 
  which 
  form 
  probably 
  the 
  

   northern 
  boundary 
  of 
  the 
  Antarctic 
  circle, 
  and 
  along 
  the 
  lines 
  of 
  

   which 
  some 
  species 
  are 
  now 
  satisfactorily 
  known 
  to 
  be 
  extensively 
  

   distributed*. 
  This 
  south-westerly 
  current 
  leaves 
  on 
  its 
  east 
  the 
  

   western 
  shores 
  of 
  Australia, 
  and 
  it 
  seemed 
  to 
  be 
  interesting 
  to 
  make 
  

   a 
  definite 
  examination 
  of 
  this 
  question 
  : 
  Have 
  the 
  species 
  in 
  extend- 
  

   ing 
  westward 
  along 
  the 
  northern 
  shores 
  of 
  Australia, 
  and 
  thence 
  

   southward, 
  become 
  specially 
  modified 
  in 
  their 
  journey 
  ? 
  

  

  Interesting 
  as 
  such 
  a 
  discovery 
  would 
  have 
  been, 
  it 
  must 
  be 
  said 
  

   that 
  the 
  view 
  that 
  there 
  might 
  be 
  a 
  fauna 
  special 
  and 
  peculiar 
  to 
  the 
  

   western 
  coast 
  of 
  Australia 
  cannot 
  be 
  in 
  any 
  way 
  sustained 
  either 
  by 
  a 
  

   consideration 
  of 
  the 
  Echinoidea 
  of 
  the 
  present 
  collection 
  or 
  by 
  a 
  

   general 
  review 
  of 
  the 
  distribution 
  of 
  the 
  Order. 
  

  

  The 
  voj'age 
  of 
  the 
  'Gazelle' 
  resulted 
  in 
  the 
  discovery 
  at 
  Naturalist 
  

   Channel, 
  or 
  Mermaid 
  Straits, 
  of 
  four 
  of 
  the 
  species 
  noted 
  in 
  our 
  list 
  

   — 
  Sahnacis 
  sulcata, 
  Echinometra 
  lucunter, 
  Lovenia 
  elonqata, 
  and 
  

   Breynia 
  australasice 
  ; 
  Sahnacis 
  alexanclri 
  (r/lobator) 
  is 
  known 
  from 
  

   the 
  west 
  coast 
  ; 
  and 
  all 
  the 
  following 
  species 
  would 
  appear 
  to 
  be 
  

   found 
  on 
  the 
  westerly 
  as 
  well 
  as 
  the 
  easterly 
  coasts 
  of 
  the 
  continent 
  : 
  

   — 
  Qoniocidaris 
  geranoides, 
  O. 
  tubaria, 
  Centrostephanus 
  rodgcrsi, 
  

   Amhlyp7ieustes 
  griseus, 
  A. 
  jxillidus, 
  Microcyphus 
  zigzag, 
  Splicer- 
  

   echinus 
  australasice, 
  and 
  Echinocardium 
  austrrde 
  ; 
  or 
  about 
  25 
  per 
  

   cent, 
  of 
  the 
  Echinoidea 
  found 
  on 
  other 
  parts 
  of 
  the 
  Australian 
  coast 
  

   have 
  already 
  been 
  found 
  on 
  the 
  western 
  shores, 
  and 
  no 
  species 
  are 
  

   known 
  to 
  be 
  peculiar 
  to 
  them. 
  

  

  It 
  is, 
  no 
  doubt, 
  reasonable 
  to 
  suppose 
  that 
  the 
  species 
  which 
  are 
  

   widely 
  distributed 
  in 
  the 
  Indo-Pacific 
  will 
  be 
  found 
  on 
  the 
  western 
  

   coast 
  of 
  Australia, 
  and 
  that 
  the 
  more 
  southerly 
  forms 
  will 
  be 
  repre- 
  

   sented 
  by 
  the 
  species 
  oi'Amhlypneustes, 
  Microcyphus, 
  or 
  Holopneustes, 
  

   which 
  we 
  are 
  in 
  the 
  habit 
  of 
  regarding 
  as 
  truly 
  " 
  Australian." 
  

  

  A 
  somewhat 
  similar 
  story 
  is 
  told 
  by 
  the 
  Ophiuroids. 
  

  

  Till 
  lately 
  fourteen 
  species 
  of 
  Asteroids 
  were 
  known 
  only 
  from 
  

   Western 
  or 
  South-western 
  Australia 
  ; 
  but 
  Mr. 
  Woods 
  reports 
  Culcita 
  

   pentaiigidaris 
  from 
  N.E. 
  Australia, 
  Pentagoyiaster 
  dubeni 
  from 
  S. 
  

   Australia, 
  and 
  Tosia 
  austraUs 
  from 
  S. 
  Australia 
  and 
  Tasmania 
  ; 
  

   while 
  the 
  present 
  collection 
  enlarges 
  the 
  range 
  of 
  Patiria 
  crassa. 
  

  

  Although 
  there 
  appeared 
  at 
  one 
  time 
  to 
  be 
  good 
  reason 
  for 
  dis- 
  

   agreeing 
  with 
  Martint, 
  the 
  present 
  amount 
  and 
  weight 
  of 
  evidence 
  

   in 
  our 
  hands 
  goes 
  to 
  point 
  to 
  the 
  existence 
  of 
  a 
  tropical 
  oceanic 
  

   fauna 
  ; 
  to-day, 
  as 
  in 
  those 
  Tei'tiary 
  times 
  when 
  a 
  wider 
  sea 
  separated 
  

   the 
  Australian 
  from 
  the 
  Asiatic 
  continent, 
  there 
  are 
  forms 
  whose 
  

   breadth 
  of 
  range 
  is 
  coincident 
  rather 
  with 
  isothermal 
  lines 
  than 
  

   topographical 
  boundaries. 
  

  

  For 
  the 
  elucidation 
  of 
  the 
  details 
  of 
  this 
  tropical 
  fauna, 
  we 
  may 
  

   look 
  with 
  almost 
  more 
  than 
  confidence 
  to 
  the 
  information 
  afforded 
  

   by 
  the 
  species 
  of 
  Crinoids 
  : 
  here, 
  however, 
  the 
  cabinet 
  naturalist 
  can 
  

   as 
  yet 
  only 
  appeal 
  to 
  the 
  collector. 
  

  

  * 
  Evidence 
  as 
  to 
  this 
  was 
  given 
  by 
  the 
  earlier 
  collections 
  of 
  the 
  'Alert' 
  in 
  

   the 
  Straits 
  of 
  Magellan 
  (see 
  P. 
  Z. 
  S. 
  1881, 
  pp. 
  1-141). 
  

   t 
  Notes 
  Leyd. 
  Miis. 
  ii. 
  p. 
  73 
  et 
  seq. 
  

  

  N 
  

  

  