﻿618 
  COLLECTIONS 
  FROM 
  THE 
  WESTERN 
  INDIAN 
  OCEAN. 
  

  

  approximately 
  cylindrical 
  stems, 
  50 
  by 
  13 
  and 
  80 
  by 
  20 
  millim. 
  re- 
  

   spectively 
  in 
  greatest 
  height 
  and 
  thickness, 
  arising 
  close 
  together 
  

   from 
  a 
  common 
  rocky 
  base. 
  The 
  lower 
  end 
  of 
  the 
  larger 
  one 
  is 
  

   almost 
  smooth 
  for 
  a 
  distance 
  of 
  about 
  8 
  millim. 
  ; 
  the 
  remainder, 
  as 
  

   well 
  as 
  the 
  whole 
  of 
  the 
  smaller 
  stem, 
  is 
  beset 
  with 
  small, 
  slender, 
  

   wedge-shaped 
  or 
  pyramidal 
  eminences, 
  sometimes 
  forked, 
  2-3 
  millim. 
  

   high, 
  about 
  2 
  millim. 
  in 
  diameter 
  at 
  their 
  bases 
  and 
  2-4 
  millim. 
  

   apart 
  at 
  their 
  summits 
  ; 
  the 
  general 
  surface 
  between 
  these 
  processes 
  

   is 
  honeycombed 
  with 
  circular 
  openings, 
  "5 
  to 
  1-OmiUim. 
  in 
  diameter 
  

   and 
  '25 
  to 
  1*0 
  millim, 
  apart. 
  Consistence 
  rigid, 
  slightly 
  compres- 
  

   sible, 
  tough. 
  Colour 
  very 
  pale 
  buff. 
  

  

  Skeleton 
  typically 
  Axinella-like 
  ; 
  fibre 
  3 
  or 
  4 
  spicules 
  broad; 
  

   spicules 
  united 
  by 
  dense, 
  very 
  pale 
  yellow 
  horny 
  fibre 
  ; 
  axial 
  

   meshes 
  close, 
  '18 
  to 
  -3 
  millim. 
  across, 
  the 
  reticulation 
  extending 
  to 
  

   exterior 
  of 
  sponge. 
  Sarcode 
  pale 
  yellow, 
  subtransparent. 
  Spicules 
  

   smooth 
  acuate, 
  curved 
  more 
  or 
  less 
  boldly 
  at 
  from 
  one 
  third 
  to 
  

   one 
  half 
  of 
  the 
  distance 
  from 
  the 
  base 
  ; 
  base 
  well 
  rounded 
  ; 
  spicules 
  

   tapering 
  to 
  sharp 
  points 
  from 
  about 
  their 
  middle 
  ; 
  size 
  "35 
  by 
  '019 
  

   millim. 
  In 
  Lamarck's 
  specimen 
  the 
  surface-tufts 
  are 
  smaller 
  and 
  

   only 
  1-2 
  millim. 
  apart, 
  the 
  sponge 
  is 
  more 
  fiattened 
  than 
  here, 
  and 
  

   the 
  spicules 
  are 
  slightly 
  smaller, 
  viz. 
  -31 
  by 
  '018 
  millim. 
  

  

  Hab. 
  Darros 
  Island, 
  Amirante 
  group, 
  22 
  fms. 
  

  

  Distribution. 
  King 
  Island, 
  Australia 
  (LamarcJc). 
  

  

  41. 
  Axinella 
  proliferans. 
  (Plate 
  LIII. 
  figs. 
  E, 
  E' 
  ; 
  

   Plate 
  LIV. 
  fig. 
  c.) 
  

  

  Erect, 
  with 
  short 
  flattened 
  stem, 
  expanding 
  into 
  fiabellate 
  fronds, 
  

   which 
  towards 
  their 
  ends 
  proliferate 
  into 
  secondary 
  fiabellate 
  frondlets 
  

   which 
  assume 
  a 
  course 
  parallel 
  to 
  that 
  of 
  the 
  main 
  frond 
  ; 
  as 
  the 
  

   latter 
  is 
  frequently 
  plicate 
  at 
  its 
  free 
  margin, 
  the 
  aspect 
  on 
  looking 
  

   down 
  at 
  a 
  large 
  specimen 
  from 
  above 
  is 
  that 
  of 
  a 
  number 
  of 
  irregular 
  

   funnel-shaped 
  cells, 
  bounded 
  by 
  lamellar 
  walls, 
  roughened 
  by 
  very 
  

   numerous 
  slashed 
  ascending 
  ridges. 
  Surface 
  of 
  frond 
  beset, 
  at 
  in- 
  

   tervals 
  of 
  about 
  4 
  millim., 
  with 
  sharp 
  ridges 
  3-4 
  millim. 
  high 
  (5 
  

   or 
  6 
  millim. 
  near 
  upper 
  margin) 
  ; 
  the 
  ridges 
  notched 
  at 
  intervals 
  of 
  

   about 
  3 
  millim. 
  by 
  ascending 
  teeth, 
  1-3 
  millim. 
  high, 
  or 
  altogether 
  

   replaced 
  by 
  longitudinal 
  series 
  of 
  flattened, 
  notched 
  teeth. 
  

  

  Vents 
  in 
  spirit- 
  specimen 
  formed 
  by 
  circular 
  openings, 
  1-2 
  millim. 
  

   wide, 
  leading 
  obliquely 
  downwards, 
  scattered 
  between 
  the 
  bases 
  of 
  

   the 
  laeiniate 
  surface-tufts 
  and 
  ridges 
  of 
  the 
  sponges, 
  chiefly 
  near 
  

   the 
  free 
  margins 
  of 
  the 
  latter. 
  Texture 
  in 
  dry 
  state 
  tough, 
  sub- 
  

   elastic 
  ; 
  of 
  stem 
  and 
  midribs 
  firm, 
  woody, 
  of 
  margins 
  of 
  fronds 
  and 
  

   ridges 
  fiexible 
  ; 
  in 
  spirit, 
  all 
  parts 
  relatively 
  more 
  pliable. 
  Colour 
  

   in 
  dry 
  state 
  pale 
  yellow-brown 
  to 
  rufous-brown, 
  in 
  spirit 
  pale 
  salmon- 
  

   colour. 
  

  

  Cortical 
  skeleton 
  appearing 
  on 
  margins 
  of 
  surface-tufts 
  and 
  in 
  some 
  

   places 
  on 
  face 
  of 
  frond 
  as 
  tufts 
  composed 
  of 
  a 
  few 
  of 
  spicule 
  no. 
  1, 
  

   connected 
  by 
  their 
  bases 
  ; 
  in 
  main 
  stem 
  consisting 
  of 
  confused 
  linear 
  

  

  