﻿606 
  COLLECTIONS 
  FROM 
  THE 
  WESTERN 
  INDIA.N 
  OCEAN. 
  

  

  sible, 
  readily 
  torn. 
  Colour 
  pale 
  brown 
  ; 
  general 
  appearance 
  that 
  of 
  

   soft 
  leather. 
  Main 
  skeleton 
  composed 
  of 
  nmltispicular 
  secondary 
  

   tracts 
  of 
  loosely 
  aggregated 
  spicules, 
  8- 
  to 
  15-serial, 
  placed 
  parallel 
  

   to 
  the 
  surface 
  at 
  intervals 
  of 
  '2 
  to 
  '3 
  millim,, 
  and 
  of 
  primary 
  lines 
  

   represented 
  by 
  groups 
  of 
  4 
  to 
  10 
  spicules 
  crossing 
  the 
  intervals 
  of 
  

   the 
  secondaries, 
  ladder-like, 
  at 
  intervals 
  of 
  about 
  '3 
  millim., 
  the 
  

   spicules 
  composing 
  these 
  groups 
  being 
  so 
  loosely 
  associated 
  as 
  often 
  

   hardly 
  to 
  be 
  in 
  contact 
  ; 
  they 
  turn 
  to 
  one 
  side 
  at 
  the 
  points 
  at 
  

   which 
  they 
  come 
  into 
  contact 
  with 
  the 
  secondaries, 
  thus 
  rounding 
  

   off 
  the 
  angles 
  of 
  the 
  otherwise 
  rectangular 
  spaces 
  of 
  the 
  meshwork. 
  

   Dermal 
  skeleton 
  formed 
  by 
  the 
  outward 
  projection 
  of 
  slender 
  primary 
  

   tufts 
  of 
  spicules, 
  2 
  to 
  4 
  spicules 
  broad. 
  Sarcode 
  pale 
  brownish 
  

   yellow, 
  subtransparent. 
  Spicules 
  smooth 
  acerate, 
  slightly 
  curved, 
  

   tapering 
  to 
  sharp 
  points 
  from 
  2 
  or 
  3 
  diameters 
  from 
  ends 
  ; 
  size 
  -IS 
  

   by 
  -007 
  millim. 
  

  

  Hab. 
  Seychelle 
  Islands, 
  2 
  fms. 
  ; 
  Marie 
  Louise 
  Island, 
  Amirante 
  

   group, 
  16-17 
  fms. 
  ; 
  bottom 
  coral. 
  

  

  This 
  species, 
  by 
  its 
  polyspieular 
  fibre 
  and 
  compact 
  structure, 
  differs 
  

   from 
  most 
  species 
  of 
  Reniera. 
  Indeed 
  the 
  former 
  character 
  would 
  

   appear 
  to 
  ally 
  it 
  to 
  Schmidtia 
  ; 
  but 
  it 
  is 
  remarkable 
  that, 
  probably 
  

   in 
  connexion 
  with 
  the 
  thinness 
  of 
  the 
  wall 
  and 
  consequent 
  need 
  of 
  

   resistance 
  to 
  lateral 
  pressure, 
  it 
  is 
  the 
  secondary, 
  and 
  not 
  the 
  primary, 
  

   fibres 
  which 
  are 
  the 
  stoutest 
  ; 
  possibly 
  it 
  is 
  to 
  the 
  exigencies 
  entailed 
  

   by 
  the 
  peculiar 
  external 
  form 
  that 
  the 
  whole 
  of 
  the 
  internal 
  pecu- 
  

   liarities 
  are 
  due. 
  The 
  largest 
  of 
  the 
  specimens, 
  which 
  are 
  somewhat 
  

   fragmentary, 
  measures 
  30 
  millim. 
  high 
  by 
  18 
  miUim. 
  in 
  extreme 
  

   breadth. 
  

  

  25. 
  Reniera 
  cribriformis. 
  (Plate 
  LIII. 
  fig. 
  G 
  ; 
  Plate 
  LIV. 
  fig. 
  o.) 
  

  

  Some 
  fragments 
  in 
  spirit 
  of 
  a 
  hollow 
  cushion-shaped 
  sponge 
  seem 
  

   worthy 
  of 
  a 
  description, 
  as 
  it 
  has 
  characters 
  by 
  which 
  it 
  may 
  be 
  

   recognized. 
  The 
  wall 
  is 
  "5 
  to 
  3 
  millim. 
  thick, 
  compact, 
  folded 
  back 
  

   at 
  the 
  margin 
  so 
  as 
  to 
  enclose 
  a 
  space 
  below 
  the 
  surface. 
  Surface 
  

   very 
  even 
  and 
  glabrous, 
  perforated 
  at 
  intervals 
  of 
  1-5 
  millim. 
  by 
  

   circular 
  vents, 
  -5 
  to 
  2-5 
  millim. 
  in 
  diameter. 
  Consistence 
  elastic, 
  

   rather 
  firm 
  ; 
  colour 
  pale 
  dull 
  brown. 
  Primary 
  fibres 
  of 
  main 
  skele- 
  

   ton 
  about 
  -18 
  millim. 
  apart, 
  vertical 
  to 
  surface, 
  spicules 
  2-3-scrial; 
  

   secondary 
  fibre 
  represented 
  by 
  separate 
  spicules, 
  traversing 
  at 
  various 
  

   angles 
  the 
  spaces 
  between 
  the 
  primaries. 
  Dermal 
  skeleton 
  a 
  close 
  

   meshwork 
  of 
  irregularly 
  disposed 
  single 
  spicules, 
  not 
  united 
  to 
  form 
  

   fibres. 
  Sarcode 
  transparent, 
  almost 
  colourless. 
  Spicule 
  smooth, 
  sub- 
  

   cylindrical 
  acerate, 
  very 
  slightly 
  curved, 
  tapering 
  from 
  near 
  centre 
  

   to 
  points 
  of 
  various 
  degrees 
  of 
  bluntness 
  ; 
  size 
  -2 
  by 
  '007 
  millim. 
  

  

  Hab. 
  Seychelle 
  Islands, 
  12 
  fms. 
  ; 
  bottom 
  coral. 
  

  

  This 
  species 
  seems 
  to 
  approach 
  R. 
  testitdinaria, 
  Lamarck 
  (see 
  

   Australian 
  Report), 
  in 
  the 
  tendency 
  of 
  its 
  spiciiles 
  to 
  assume 
  the 
  

   cylindrical 
  form. 
  

  

  Carter's 
  " 
  Reniera, 
  dark 
  brown 
  " 
  from 
  the 
  Gulf 
  of 
  Manaar 
  (Ann. 
  

   & 
  Mag. 
  N. 
  H. 
  1880, 
  vi, 
  p. 
  48), 
  differs 
  decidedly 
  from 
  this 
  in 
  its 
  

  

  