﻿SPONGIIDA. 
  379 
  

  

  and 
  non-rectangular 
  arrangement 
  with 
  those 
  of 
  Euspongia,, 
  and, 
  as 
  

   stated 
  already, 
  foreign 
  bodies 
  are 
  the 
  exception 
  even 
  in 
  the 
  surface- 
  

   tufts 
  ; 
  the 
  diameter 
  of 
  the 
  fibres 
  is 
  "4 
  to 
  -7 
  millim. 
  (Ehlcrs 
  gives 
  -5 
  

   to 
  '8), 
  except 
  in 
  the 
  delicate 
  Ditela-netw 
  ork 
  of 
  the 
  surface 
  and 
  in- 
  

   terstices, 
  where 
  it 
  is 
  •0085 
  to 
  '022 
  millim. 
  Ehlers 
  says 
  that 
  the 
  

   fibres 
  contain 
  " 
  in 
  der 
  Axe 
  vereinzelte 
  sehr 
  diinne 
  spitz-spitze 
  

   Nadcln 
  (0-1 
  mm. 
  lang, 
  -006 
  mm. 
  breit) 
  welche 
  nur 
  in 
  den 
  kegel- 
  

   formigen 
  Zuspitzungen 
  an 
  der 
  Oberfiiiche 
  des 
  Schwammes 
  etwas 
  

   dichter 
  gehiiuft 
  sind." 
  Their 
  occurrence 
  singly 
  (" 
  vereinzelte 
  ") 
  and 
  

   not 
  in 
  longitudinal 
  series, 
  if 
  that 
  is 
  what 
  is 
  implied, 
  is 
  not 
  the 
  usual 
  

   mode 
  of 
  occurrence 
  of 
  spicules 
  in 
  the 
  fibres 
  of 
  Chalinidas 
  (though 
  it 
  

   occurs 
  occasionally 
  in 
  some 
  fibres 
  of 
  Cl(idochalina'), 
  nor 
  is 
  their 
  

   greater 
  abundance 
  in 
  the 
  surface-tufts, 
  so 
  far 
  as 
  I 
  know, 
  usual 
  in 
  

   this 
  family. 
  These 
  statements 
  appear 
  to 
  me 
  to 
  point 
  towards 
  the 
  

   true 
  explanation 
  of 
  the 
  nature 
  of 
  these 
  spicules, 
  viz. 
  that 
  they 
  are 
  

   foreign, 
  and 
  taken 
  in 
  (as 
  is 
  usually 
  the 
  case 
  in 
  Easjyongki) 
  as 
  foreign 
  

   bodies 
  in 
  small 
  quantities 
  into 
  the 
  surface-tufts. 
  A 
  re-examination 
  

   of 
  the 
  original 
  specimen 
  is 
  desirable. 
  If 
  Esper's 
  species 
  is 
  a 
  Chalinid, 
  

   then 
  the 
  present 
  species 
  is 
  a 
  Easpongia-\sovLioY])\\ 
  oi 
  a 
  Chalinid 
  form, 
  

   like 
  the 
  Chalinopsid 
  representatives 
  of 
  Siphoiwchalina 
  and 
  Pachi/cha- 
  

   T-ina 
  which 
  Schmidt 
  (Spong. 
  Meerbusen 
  Mexico, 
  p. 
  80) 
  has 
  described 
  

   as 
  SiphonoGlialinopsis 
  and 
  Puchijchaliiiopsis. 
  

  

  I 
  have 
  satisfied 
  myself 
  that 
  another 
  explanation 
  which 
  might 
  be 
  

   suggested, 
  viz. 
  the 
  dissolution 
  of 
  the 
  spicules 
  from 
  the 
  fibre 
  of 
  the 
  

   Sponge 
  (as 
  in 
  Carter's 
  Aplij^ina 
  chalinoides, 
  afterwards 
  found 
  to 
  

   be 
  a 
  true 
  Chalinid), 
  cannot 
  apply 
  to 
  this 
  case. 
  I 
  have 
  studied 
  

   the 
  fibre 
  very 
  carefully, 
  with 
  and 
  without 
  the 
  aid 
  of 
  potash, 
  and 
  can 
  

   assert 
  that 
  it 
  never 
  possessed 
  "proper" 
  spicules. 
  

  

  The 
  respective 
  localities 
  (Cape 
  and 
  Torres 
  Straits) 
  perhaps 
  con- 
  

   stitute 
  relative 
  objections 
  to 
  the 
  specific 
  identity 
  of 
  the 
  present 
  with 
  

   Esper's 
  species. 
  

  

  Bab. 
  West 
  Island, 
  Torres 
  Straits. 
  

  

  Distribution. 
  Esper's 
  species 
  is 
  from 
  the 
  Cape 
  of 
  Good 
  Hope. 
  

  

  3. 
  Euspongia 
  officinalis, 
  Linne, 
  var. 
  cavernosa. 
  (Plate 
  XLI. 
  fig. 
  g.) 
  

  

  From 
  a 
  depth 
  of 
  10 
  fathoms 
  in 
  Torres 
  Straits 
  we 
  have 
  a 
  small 
  

   turnip-like 
  sponge, 
  unfortunately 
  preserved 
  only 
  in 
  the 
  dry 
  state, 
  

   which 
  to 
  the 
  unaided 
  eye 
  presents 
  the 
  general 
  appearance 
  of 
  a 
  Rhi- 
  

   zocJmli 
  jia 
  JistuJosa, 
  with 
  several 
  tubular 
  processes, 
  10 
  to 
  35 
  millim. 
  

   long 
  and 
  8 
  to 
  10 
  millim. 
  in 
  greatest 
  median 
  diameter, 
  on 
  its 
  upper 
  

   surface 
  ; 
  these 
  processes 
  are, 
  however, 
  ragged 
  in 
  outline 
  at 
  their 
  

   distal 
  ends, 
  and 
  evidently 
  in 
  life 
  opened 
  through 
  the 
  fringed 
  aper- 
  

   ture, 
  now 
  obscured 
  by 
  the 
  falling 
  together 
  of 
  the 
  sides 
  ; 
  their 
  sides 
  are 
  

   in 
  some 
  cases 
  fenesti'ate. 
  The 
  body 
  of 
  the 
  sponge 
  is 
  rudely 
  globular, 
  

   and 
  is 
  drawn 
  iip 
  above 
  into 
  monticular 
  elevations, 
  which 
  are 
  termi- 
  

   nated 
  by 
  the 
  tubes 
  just 
  described 
  ; 
  the 
  base 
  is 
  somewhat 
  flattened, 
  

   and 
  has 
  apparently 
  been 
  attached 
  at 
  three 
  points 
  to 
  rock 
  or 
  gravel 
  at 
  

   the 
  sea-bottom, 
  portions 
  of 
  which 
  are 
  still 
  left 
  imbedded 
  in 
  the 
  sponge. 
  

   The 
  chief 
  horizontal 
  diameters 
  of 
  the 
  sponge-body 
  are 
  45 
  and 
  55 
  

  

  