﻿448 
  COLLECTIONS 
  FROM 
  MELANESIA. 
  

  

  apparently 
  partly 
  formed 
  by 
  upgrowths 
  from 
  short 
  stems 
  placed 
  

   beside 
  it, 
  which, 
  though 
  now 
  single, 
  appears 
  to 
  have 
  been 
  originally 
  

   compound 
  also 
  ; 
  one 
  surface 
  of 
  this 
  expansion 
  is 
  almost 
  level, 
  but 
  

   honeycombed 
  densely 
  with 
  openings 
  with 
  rounded 
  edges, 
  varying 
  

   from 
  1 
  to 
  4 
  millira. 
  iu 
  diameter 
  ; 
  the 
  other 
  surface 
  is 
  broken 
  up 
  into 
  

   seven 
  more 
  or 
  less 
  pronounced 
  vertical 
  ridges, 
  irregular 
  and 
  fre- 
  

   quently 
  interrupted, 
  3 
  to 
  10 
  millim. 
  in 
  height 
  ; 
  this 
  surface 
  and 
  its 
  

   ridges 
  are 
  also 
  strongly 
  honeycombed, 
  and 
  between 
  the 
  openings 
  

   usually 
  project 
  points 
  and 
  ridges 
  of 
  sponge-tissue. 
  It 
  measures 
  

   130 
  millim. 
  (5g 
  inches) 
  in 
  breath, 
  120 
  millim. 
  (4^ 
  inches) 
  in 
  height. 
  

   The 
  second 
  specimen 
  is 
  strap-shaped, 
  24 
  to 
  30 
  millim. 
  across, 
  some- 
  

   what 
  abruptly 
  bent 
  at 
  one 
  point, 
  and 
  terminated 
  by 
  two 
  smaU 
  lobes 
  ; 
  

   like 
  the 
  other 
  specimen, 
  one 
  surface 
  is 
  comparatively 
  level 
  and 
  is 
  

   honeycombed 
  rather 
  minutely 
  (openings 
  "3 
  to 
  -5 
  millim. 
  in 
  diameter), 
  

   while 
  the 
  other 
  is 
  rugose, 
  from 
  the 
  presence 
  of 
  several 
  demi-canals, 
  

   about 
  2 
  to 
  4 
  millim. 
  across, 
  which 
  run 
  from 
  the 
  middle 
  to 
  the 
  margin 
  

   of 
  the 
  frond 
  ; 
  the 
  surface 
  between 
  them 
  is 
  minutely 
  honeycombed 
  and 
  

   drawn 
  up 
  into 
  a 
  few 
  sharp 
  points 
  and 
  ridges. 
  The 
  colour 
  is 
  darkish 
  

   grey, 
  varying 
  to 
  greenish 
  iu 
  both 
  specimens. 
  The 
  spiculation 
  is 
  

   essentially 
  that 
  of 
  the 
  above-mentioned 
  form 
  of 
  C. 
  reinivardti, 
  but 
  

   the 
  skeleton 
  smooth 
  acuate 
  is 
  only 
  '0003 
  to 
  '0079 
  millim. 
  in 
  dia- 
  

   meter, 
  and 
  the 
  short, 
  stouter, 
  smooth 
  acuate 
  is 
  wanting 
  ; 
  this 
  slight 
  

   difference 
  in 
  spiculation 
  appears 
  to 
  justify 
  the 
  separation 
  of 
  this 
  

   form 
  under 
  a 
  distinct 
  varietal 
  name. 
  It 
  is 
  perhaps 
  as 
  nearly 
  related 
  

   to 
  the 
  original 
  form 
  as 
  the 
  first-mentioned 
  specimens. 
  The 
  remark- 
  

   able 
  fan-shaped 
  specimen 
  appears 
  (having 
  regard 
  to 
  the 
  multiple 
  

   character 
  of 
  its 
  base) 
  to 
  be 
  made 
  up 
  of 
  several 
  " 
  persons 
  " 
  which 
  

   have 
  united 
  to 
  form 
  a 
  single 
  symmetrical-frond. 
  

   Ilab. 
  Bird 
  Island, 
  N.E. 
  Australia, 
  coral-reef. 
  

  

  78. 
  Clathria 
  frondifera. 
  

   (Plate 
  XLII. 
  fig. 
  i 
  ; 
  and 
  Part 
  II. 
  of 
  this 
  Ileport, 
  Plate 
  LIII. 
  fig. 
  J.) 
  

  

  Halichondria 
  frondifera, 
  Boiverbcuik, 
  Proc. 
  Zool. 
  Soc. 
  1875, 
  p. 
  2S8. 
  

   Amphilectus 
  froudifer, 
  Vosmaer, 
  Notes 
  Roy. 
  Mus. 
  Netherl. 
  ii. 
  p. 
  115. 
  

  

  A 
  very 
  common 
  species, 
  especially 
  in 
  Torres 
  Straits. 
  At 
  first 
  

   I 
  was 
  inclined 
  to 
  separate 
  the 
  specimens 
  from 
  Bowerbank's 
  

   species 
  on 
  account 
  of 
  the 
  greater 
  development 
  of 
  ceratinous 
  sub- 
  

   stance 
  investing 
  the 
  lines 
  of 
  skeleton-spicules. 
  In 
  the 
  Australian 
  

   specimens 
  this 
  occupies 
  from 
  half 
  to 
  two 
  thirds 
  of 
  the 
  diameter 
  of 
  

   the 
  fibres, 
  while 
  in 
  the 
  type 
  specimen 
  from 
  the 
  Straits 
  of 
  Malacca 
  

   its 
  place 
  is 
  often 
  almost 
  entirely 
  taken 
  by 
  spicules, 
  and 
  extends 
  to 
  

   half 
  the 
  diameter 
  of 
  the 
  fibre 
  only 
  in 
  some 
  cases. 
  The 
  consistency 
  

   of 
  the 
  sponge 
  is 
  hence 
  much 
  tougher 
  and 
  more 
  elastic 
  in 
  the 
  

   Australian 
  specimens. 
  The 
  main 
  skeleton-spicules 
  are 
  much 
  stouter 
  

   in 
  the 
  Malacca 
  specimens. 
  

  

  Dr. 
  Bowerbank 
  has 
  omitted 
  to 
  describe 
  a 
  very 
  fine 
  tricurvate 
  flesh- 
  

   spiculo 
  which 
  occurs 
  both 
  in 
  his 
  specimens 
  and 
  in 
  the 
  present 
  ones. 
  

   His 
  description 
  is 
  also 
  misleading 
  in 
  not 
  stating, 
  what 
  his 
  own 
  type 
  

   specimen 
  satisfactorily 
  exhibits, 
  and 
  what 
  the 
  Australian 
  examples 
  

  

  