﻿624 
  COLLECTIONS 
  FROM 
  THE 
  WESTERN 
  INDIiJT 
  OCEAN. 
  

  

  lower 
  part 
  of 
  sponge 
  glabrous. 
  Consistence 
  is 
  spirit 
  very 
  tough, 
  

   elastic 
  ; 
  colour 
  duU 
  olivaceous 
  brown. 
  

  

  Main 
  skeleton 
  rather 
  loose, 
  formed 
  of 
  broad 
  tracts 
  of 
  loosely 
  

   aggregated 
  spicules, 
  horizontally 
  or 
  obliquely 
  arrtiuged 
  with 
  regard 
  

   to 
  the 
  surface, 
  and 
  of 
  intercrossing 
  spicules 
  loosely 
  scattered 
  between 
  

   them 
  ; 
  that 
  of 
  the 
  cortex, 
  which 
  forms 
  a 
  denser 
  layer, 
  consists 
  of 
  

   more 
  compact 
  bundles, 
  lU 
  to 
  15 
  spicules 
  broad, 
  placed 
  vertically 
  

   with 
  regard 
  to 
  the 
  surface, 
  from 
  which 
  their 
  points 
  project 
  ; 
  the 
  

   bundles 
  are 
  from 
  '1 
  to 
  "14 
  millim. 
  apart. 
  Sarcode 
  subtransparent, 
  

   bright 
  greenish 
  brown, 
  crowded 
  with 
  globular 
  cells 
  about 
  •Oil 
  millim. 
  

   broad, 
  with 
  largo 
  nucleus 
  and 
  one 
  or 
  more 
  opaque 
  granules. 
  

  

  Spicules 
  : 
  — 
  (1) 
  Skeleton 
  spinulate, 
  smooth, 
  straight 
  or 
  slightly 
  

   curved; 
  head 
  oval, 
  longitudinally 
  elongate, 
  slightly 
  flattened 
  at 
  free 
  

   end, 
  of 
  about 
  same 
  diameter 
  as 
  middle 
  of 
  shaft, 
  tapering 
  gradually 
  

   from 
  centre 
  of 
  shaft 
  to 
  sharp 
  apex 
  ; 
  size 
  of 
  spicule 
  "4 
  by 
  "OlS 
  millim. 
  

   (2) 
  Spinispirular, 
  short, 
  slender, 
  consisting 
  of 
  about 
  four 
  bends, 
  

   about 
  6 
  spines 
  to 
  a 
  bend 
  ; 
  spines 
  sharp, 
  about 
  '002 
  mUlim. 
  long 
  ; 
  

   size 
  of 
  spicule 
  -02 
  by 
  -002 
  millim. 
  (exclusive 
  of 
  spines). 
  

  

  Hah. 
  Mozambique, 
  between 
  tide-marks. 
  

  

  Distribution. 
  Mauritius 
  (Carter). 
  

  

  The 
  greatest 
  height 
  of 
  the 
  single 
  spirit-specimen 
  representing 
  this 
  

   species 
  is 
  65 
  millim. 
  (2| 
  inches), 
  the 
  greatest 
  diameter 
  25 
  millim. 
  ; 
  

   its 
  form 
  is 
  that 
  of 
  a 
  much 
  drawn-out, 
  truncate 
  cone, 
  compressed 
  so 
  

   that 
  the 
  long 
  diameter 
  is 
  about 
  twice 
  that 
  of 
  the 
  small 
  one 
  ; 
  there 
  

   is 
  a 
  nodular 
  process, 
  5 
  millim. 
  high, 
  on 
  one 
  side 
  near 
  the 
  extremity 
  ; 
  

   the 
  base 
  includes 
  a 
  large 
  amount 
  of 
  coarse 
  foreign 
  bodies. 
  The 
  

   characters 
  agree 
  well 
  with 
  those 
  given 
  by 
  Mr. 
  Carter 
  (Z. 
  c.) 
  for 
  a 
  

   fragment 
  from 
  Mauritius. 
  It 
  is 
  nearly 
  related 
  to 
  Hymeniacidon 
  

   anf/ulata 
  of 
  Bowerbank 
  (Madeira), 
  and 
  vagabunda 
  and 
  decumbens, 
  

   mihi 
  (Austi-alia, 
  this 
  Eeport, 
  Part. 
  I. 
  pp. 
  468, 
  470); 
  but 
  it 
  is 
  dis- 
  

   tinguished 
  readily 
  from 
  all 
  by 
  its 
  very 
  short 
  spinispirular 
  spicule. 
  

  

  48. 
  Tethya 
  cliftoni. 
  

  

  Tethea 
  cliftoni, 
  Bowerbank, 
  P. 
  Z. 
  S. 
  1873, 
  p. 
  16, 
  pi. 
  iii. 
  figs. 
  14-18. 
  

  

  A 
  single 
  specimen, 
  cream 
  -white, 
  covered 
  with 
  low 
  papillae 
  about 
  

   1-5 
  millim. 
  in 
  diameter. 
  The 
  species, 
  unless 
  the 
  separation 
  of 
  the 
  

   large 
  stellates 
  into 
  two 
  distinct 
  dermal 
  zones 
  proves 
  to 
  be 
  constant 
  and 
  

   distinctive, 
  can 
  hardly 
  be 
  kept 
  distinct 
  from 
  T. 
  ingalli 
  (Freemantle, 
  

   Australia) 
  and 
  T. 
  robasta 
  (Australia), 
  both 
  of 
  Bowerbank, 
  the 
  chief 
  

   difference 
  being 
  in 
  the 
  diameter 
  of 
  the 
  acuate, 
  which 
  in 
  T. 
  cliftoni 
  is 
  

   about 
  "025 
  millim., 
  in 
  T. 
  ingalli 
  '035 
  millim., 
  and 
  in 
  T. 
  robusta 
  "045 
  

   millim. 
  Again, 
  all 
  three 
  species 
  are 
  scarcely 
  more 
  than 
  varietally 
  

   distinct 
  from 
  T. 
  lyncurrum 
  of 
  Europe, 
  differing 
  from 
  it 
  mainly 
  in 
  

   the 
  greater 
  distinctness 
  of 
  the 
  heads 
  of 
  the 
  small 
  stellates, 
  

  

  Hab, 
  SeycheUe 
  Islands, 
  12 
  fms. 
  

  

  Distribution. 
  S.W. 
  Australia 
  {Bowerbank), 
  

  

  