﻿6P0NGI1DA. 
  377 
  

  

  Gelliodes 
  Jibulata, 
  lihizochalina 
  sin'japorensis, 
  var., 
  and 
  Clathria 
  

   reinwardti, 
  var. 
  subcijUndrica. 
  Ectyonidic 
  and 
  Tctractinellida 
  are 
  

   relatively 
  the 
  most 
  rich 
  in 
  species 
  in 
  this 
  siibequatorial 
  region, 
  12 
  

   out 
  of 
  the 
  17 
  species 
  collected 
  of 
  the 
  first 
  and 
  7 
  out 
  of 
  the 
  8 
  of 
  the 
  

   latter 
  group 
  being 
  obtained 
  hero. 
  It 
  is 
  remarkable 
  that 
  the 
  only 
  

   Siliceous 
  species 
  hitherto 
  recorded 
  with 
  certainty 
  from 
  the 
  locality, 
  

   so 
  far 
  as 
  I 
  am 
  aware 
  (XenosjJOHgia 
  patellifonnis, 
  (iray, 
  P. 
  Z. 
  S. 
  1858, 
  

   p. 
  229, 
  pi. 
  12), 
  has 
  not 
  appeared 
  ou 
  this 
  occasion 
  ; 
  it 
  was, 
  however, 
  

   perhaps 
  obtained 
  from 
  deep 
  water, 
  as 
  its 
  apparent 
  affinity 
  to 
  Hall- 
  

   cnemia, 
  Bowcrbank, 
  of 
  the 
  Eritish 
  seas 
  would 
  suggest, 
  and 
  no 
  speci- 
  

   mens 
  were 
  obtained 
  on 
  this 
  occasion 
  from 
  deep 
  water 
  (if 
  such 
  exists) 
  

   in 
  Torres 
  Straits. 
  

  

  Of 
  the 
  other 
  localities, 
  Port 
  Darwin 
  on 
  the 
  north-west 
  and 
  the 
  

   eastern 
  Queensland 
  coast 
  ou 
  the 
  east 
  have 
  been 
  the 
  most 
  productive. 
  

   As 
  might 
  have 
  been 
  expected 
  from 
  the 
  wide 
  extent 
  of 
  moderately 
  

   deep 
  sea 
  which 
  separates 
  Port 
  Darwin 
  from 
  Torres 
  Straits, 
  there 
  are 
  

   very 
  considerable 
  differences 
  between 
  their 
  Sponge-faunas, 
  although 
  

   a 
  larger 
  number 
  of 
  dredgings 
  made 
  at 
  the 
  former 
  would 
  probably 
  

   have 
  reduced 
  these 
  differences. 
  We 
  find, 
  however, 
  the 
  lotrocliota 
  

   {purpurea) 
  so 
  common 
  at 
  Torres 
  Straits 
  replaced 
  by 
  another 
  spe- 
  

   cies, 
  /. 
  bacuUfera; 
  OelUodes 
  fifndata 
  and 
  lihizocludina 
  singaporensis 
  

   do 
  not 
  even 
  appear 
  ; 
  the 
  Ectyonida;, 
  so 
  far 
  from 
  being 
  common, 
  have 
  

   but 
  a 
  single 
  species 
  here 
  ; 
  and 
  the 
  llenieridaj, 
  so 
  poorly 
  represented 
  

   at 
  Torres 
  Straits, 
  have 
  here 
  10 
  species. 
  Onlj^ 
  a 
  few 
  species 
  are 
  here 
  

   shown 
  to 
  extend 
  across 
  the 
  Gulf 
  of 
  Carpentaria 
  {Toxoclialina 
  foli- 
  

   oides, 
  Rluzocludina 
  cancdis, 
  Stelletta 
  purpurea') 
  . 
  

  

  The 
  Arafura 
  Sea 
  represents 
  a 
  somewhat 
  deeper 
  area, 
  but, 
  as 
  might 
  

   have 
  been 
  expected, 
  shows 
  affinities 
  with 
  Torres 
  Straits 
  on 
  the 
  one 
  

   hand 
  and 
  Port 
  Darwin 
  ou 
  the 
  other 
  ; 
  3 
  species 
  of 
  lihizochalina 
  and 
  

   2 
  Stellettai 
  are 
  its 
  chief 
  representatives 
  in 
  the 
  collection. 
  

  

  The 
  Queensland 
  coast 
  does 
  not 
  appear 
  to 
  be 
  so 
  rich 
  in 
  Sponges 
  as 
  

   in 
  Alcyonaria 
  ; 
  in 
  particular, 
  the 
  absence 
  of 
  Tctractinellida 
  and 
  

   almost 
  total 
  absence 
  of 
  Suberitidse 
  characterizes 
  the 
  collections 
  

   obtained 
  from 
  this 
  region. 
  The 
  occurrence 
  either 
  here 
  or 
  in 
  Torres 
  

   Straits 
  of 
  the 
  whole 
  of 
  the 
  12 
  species 
  assigned 
  to 
  species 
  described 
  

   by 
  Lamarck 
  is 
  evidence 
  in 
  favour 
  of 
  the 
  view 
  that 
  it 
  was 
  here 
  that 
  a 
  

   considerable 
  proportion 
  of 
  the 
  Sponges 
  described 
  by 
  him 
  as 
  collected 
  

   by 
  MM. 
  Peron 
  and 
  Lesueur 
  in 
  the 
  ' 
  Mers 
  Australes 
  ' 
  were 
  obtained. 
  

  

  Port 
  Jackson 
  shows 
  iieculiarities 
  connected 
  with 
  its 
  southern 
  lati- 
  

   tude, 
  producing 
  two 
  British 
  Suberitidaj 
  besides 
  South-Australian 
  

   species 
  of 
  Leuconia 
  and 
  Ilircinia 
  ; 
  still, 
  it 
  has 
  some 
  species 
  in 
  

   common 
  with 
  Torres 
  Straits. 
  Six 
  species 
  range 
  from 
  the 
  south 
  to 
  

   the 
  north 
  of 
  Australia. 
  

  

  Classification. 
  — 
  I 
  have 
  followed 
  no 
  one 
  author 
  in 
  this 
  matter. 
  

   The 
  subject 
  is 
  in 
  a 
  state 
  of 
  transition, 
  and 
  I 
  have 
  adopted 
  those 
  

   divisions 
  which 
  seemed 
  most 
  in 
  accordance 
  with 
  the 
  present 
  state 
  

   of 
  our 
  knowledge, 
  llcmarks 
  on 
  the 
  characters 
  of 
  the 
  different 
  groups 
  

   will 
  be 
  found 
  under 
  their 
  names 
  ; 
  in 
  some 
  cases 
  (especially 
  Chali- 
  

   7iidce, 
  Desmacidinidce) 
  important 
  modifications 
  in 
  scope 
  or 
  characters 
  

   seem 
  required 
  by 
  the 
  results 
  of 
  the 
  present 
  collection. 
  

  

  