﻿SPONGIIDA. 
  399 
  

  

  and 
  besides 
  being 
  primarily 
  based 
  on 
  an 
  erect 
  species, 
  requires 
  the 
  

   spicules 
  to 
  form 
  the 
  greater 
  part 
  of 
  the 
  skeleton-fibre, 
  which 
  he 
  

   reconciles 
  with 
  the 
  structure 
  of 
  G. 
  limhata 
  by 
  stating 
  that 
  the 
  

   horny 
  matter 
  in 
  this 
  species 
  shrivels 
  when 
  dried, 
  

  

  27. 
  Acervochalina 
  finitima. 
  

  

  Chalina 
  finitima, 
  Schmidt, 
  Atl. 
  Geh. 
  p. 
  33. 
  

  

  Several 
  specimens 
  agreeing 
  with 
  this 
  Atlantic 
  species. 
  They 
  

   have 
  the 
  general 
  habit 
  of 
  Glathria 
  oroides, 
  Schmidt, 
  which 
  from 
  a 
  

   low 
  massive 
  body 
  throws 
  out 
  blunt 
  spurs. 
  On 
  the 
  spurs 
  are 
  placed 
  

   numerous 
  small 
  vents, 
  1-4 
  millim. 
  in 
  diameter, 
  biserially 
  or 
  irregu- 
  

   larly 
  arranged. 
  Texture 
  in 
  spirit 
  very 
  soft 
  and 
  elastic 
  ; 
  colour 
  pale 
  

   yellowish 
  brown. 
  Skeleton 
  network 
  close, 
  rectangular 
  ; 
  fibres 
  stout, 
  

   pale 
  yellow 
  or 
  colourless 
  ; 
  spicules 
  multiserial 
  in 
  primary, 
  biserial 
  

   or 
  uniserial 
  in 
  secondary 
  fibres. 
  Sjiicules 
  smooth, 
  gradually 
  and 
  

   sharply 
  pointed 
  ; 
  size 
  about 
  -1 
  by 
  '0018 
  millim. 
  {i. 
  e. 
  a 
  little 
  thinner 
  

   than 
  in 
  West-Indian 
  specimens). 
  

  

  Hah. 
  Port 
  Jackson, 
  0-5 
  fms., 
  Percy 
  Island, 
  Queensland, 
  0-5 
  

   fms. 
  ; 
  Alert 
  Island, 
  Torres 
  Straits, 
  7 
  fms. 
  

  

  Distrihution. 
  Florida, 
  Antilles 
  (Schmidt). 
  

  

  A. 
  finitima 
  differs 
  from 
  the 
  British 
  species 
  limbata 
  in 
  its 
  general 
  

   shape, 
  that 
  of 
  limhata 
  being 
  globular 
  to 
  lobate. 
  

  

  The 
  specimens 
  measure 
  about 
  50 
  millim. 
  (2 
  inches) 
  in 
  greatest 
  

   diameter, 
  and 
  25 
  millim. 
  in 
  height. 
  

  

  28. 
  TubabuUata. 
  

  

  ? 
  Spongia 
  buUata, 
  Lamarch, 
  Ann. 
  Mvs. 
  Hist. 
  Nat. 
  xx. 
  p. 
  43 
  {nee 
  

  

  var. 
  ^) 
  ; 
  nee 
  Siphonochalina 
  hullata, 
  Schmidt. 
  

   Spongia 
  aculeata, 
  Linne, 
  pars, 
  Syst. 
  Nat. 
  ed. 
  12, 
  p. 
  1297. 
  

  

  "Wide-mouthed 
  tubes, 
  50 
  to 
  200 
  millim. 
  high 
  (2 
  to 
  8 
  inches), 
  

   rising 
  from 
  a 
  common 
  horizontal 
  lamina, 
  from 
  which 
  they 
  appear 
  

   to 
  bo 
  formed 
  by 
  the 
  reversion 
  and 
  curling 
  of 
  its 
  edges. 
  Tubes 
  

   irregular 
  in 
  lumen, 
  35 
  to 
  125 
  millim. 
  (11 
  to 
  5 
  inches) 
  in 
  maximum 
  

   diameter. 
  Surface 
  asperated 
  by 
  a 
  network 
  of 
  low 
  sharp 
  ridges, 
  besot 
  

   with 
  numerous 
  sharp 
  points, 
  1 
  to 
  3 
  millim. 
  high. 
  Mouth 
  of 
  tubes 
  

   somewhat 
  constricted, 
  inner 
  surface 
  smooth. 
  The 
  surface-tufts 
  are 
  

   seen 
  on 
  examination 
  generally 
  to 
  proceed 
  from 
  narrow 
  superficial 
  

   ridges 
  which 
  run 
  over 
  the 
  surface 
  in 
  different 
  directions. 
  The 
  pro- 
  

   longation 
  of 
  the 
  margin 
  spoken 
  of 
  by 
  Lamarck 
  is 
  not 
  to 
  be 
  made 
  

   out 
  distinctly. 
  

  

  Skeleton 
  of 
  narrow 
  rectangular 
  meslies. 
  Primary 
  fibres 
  about 
  '1 
  

   to 
  '14 
  millim., 
  secondary 
  '42 
  to 
  '7 
  millim. 
  in 
  diameter, 
  both 
  full 
  

   (in 
  most 
  places) 
  of 
  the 
  acerate 
  spicules, 
  though 
  these 
  are 
  somewhat 
  

   closely 
  aggregated. 
  Spicules 
  (i.) 
  fusiform, 
  tapering 
  to 
  sharp 
  points 
  

   from 
  within 
  about 
  two 
  diametersof 
  the 
  apices, 
  -IS 
  by 
  0095 
  millim. 
  ; 
  

   also 
  (ii.), 
  probably 
  a 
  variety 
  of 
  (i.), 
  acuatc, 
  about 
  -14 
  by 
  -0003 
  millim. 
  

  

  This 
  species 
  appears 
  to 
  be 
  widely 
  distributed 
  between 
  Japan 
  and 
  

  

  