﻿464 
  COLLECTIONS 
  FROM 
  MELANESIA. 
  

  

  LEUCOPHL(EUS. 
  

  

  Carter, 
  Ann. 
  ^ 
  Mag. 
  N. 
  II. 
  1883, 
  xii. 
  p. 
  323. 
  

  

  92. 
  Leucophloeus 
  fenestratus. 
  (Tlate 
  XLII. 
  fig. 
  s.) 
  

  

  Massive, 
  suberect, 
  terminating 
  above 
  in 
  thin 
  edges, 
  on 
  each, 
  side 
  

   of 
  which 
  open 
  wide 
  pouch-like 
  vent-cavities, 
  which 
  also 
  open 
  to 
  tho 
  

   surface 
  laterally 
  by 
  rounded 
  apertures. 
  Surface 
  minutely 
  undulating, 
  

   but 
  glabrous. 
  Texture 
  in 
  spirit 
  rather 
  tough, 
  compressible, 
  soft 
  ; 
  

   . 
  colour 
  dull 
  greyish 
  brown. 
  Main 
  skeleton 
  composed 
  of 
  irregular, 
  very 
  

   loose 
  tracts 
  of 
  spicules, 
  3 
  to 
  10 
  spicules 
  broad, 
  extending 
  in 
  various 
  

   directions 
  and 
  lying 
  at 
  various 
  angles 
  ; 
  the 
  dermis 
  is 
  supported 
  

   by 
  some 
  closely 
  set 
  sub 
  vertical 
  tracts 
  of 
  similar 
  character 
  lying 
  

   between 
  the 
  subcortical 
  crypts. 
  Dermal 
  skeleton 
  composed 
  of 
  very 
  

   loose 
  and 
  irregular 
  tracts 
  or 
  aggregated 
  masses 
  of 
  spicules 
  inter- 
  

   crossing 
  so 
  as 
  to 
  form 
  an 
  almost 
  continuous 
  sheet, 
  in 
  the 
  intervals 
  

   of 
  which 
  are 
  placed 
  the 
  pores, 
  Sarcode 
  pale 
  brown, 
  subtransparent. 
  

   Spicule 
  smooth 
  straight, 
  or 
  almost 
  straight 
  acuate, 
  tapering 
  gra- 
  

   dually 
  from 
  centre 
  to 
  moderately 
  sharp 
  point, 
  and 
  from 
  centre 
  

   gradually 
  to 
  well-rounded 
  undilated 
  base, 
  which 
  has, 
  however, 
  only 
  

   about 
  half 
  the 
  diameter 
  of 
  the 
  centre 
  of 
  the 
  shaft 
  ; 
  size 
  of 
  spicule 
  

   •5 
  to 
  -8 
  by 
  -019 
  to 
  -022 
  miUim. 
  

  

  Hah. 
  Port 
  Darwin, 
  8-12 
  fms. 
  ; 
  bottom 
  sand 
  and 
  mud. 
  

  

  The 
  height 
  of 
  the 
  single 
  specimen 
  is 
  38 
  millim., 
  greatest 
  diameter 
  

   (at 
  base) 
  20 
  millim. 
  ; 
  it 
  forms 
  an 
  irregular, 
  elongated 
  i^yramid, 
  with 
  

   the 
  apex 
  flattened 
  out 
  and 
  somewhat 
  twisted. 
  In 
  size 
  and 
  shape 
  

   of 
  the 
  spicules 
  the 
  species 
  resembles 
  Ihjinenkicidon 
  crustula. 
  Bower- 
  

   bank 
  (Mon. 
  Brit. 
  Spong. 
  ii. 
  p. 
  185), 
  from 
  the 
  British 
  Seas, 
  which 
  is, 
  

   however, 
  massive 
  or 
  mammillated 
  and, 
  owing 
  to 
  the 
  inferior 
  diameter 
  

   (•012 
  millim.) 
  of 
  the 
  spicule, 
  shows 
  the 
  slenderness 
  of 
  the 
  basal 
  end 
  

   much 
  less 
  distinctly. 
  It 
  is 
  nearly 
  related 
  to 
  L. 
  massalis, 
  Carter 
  

   (I. 
  c), 
  from 
  ^y. 
  Australia, 
  but 
  is 
  darker 
  in 
  colour, 
  is 
  less 
  distinctly 
  

   penicillate, 
  and 
  has 
  the 
  spicule 
  rather 
  larger. 
  

  

  Leucophloeus 
  fenestratus, 
  var. 
  (Plate 
  XLIII. 
  fig. 
  g.) 
  

  

  A 
  dry, 
  upright, 
  flattened 
  specimen, 
  which 
  has 
  grown 
  around 
  a 
  

   Hydroid 
  bush, 
  appears 
  closely 
  allied 
  to 
  the 
  above 
  species. 
  It 
  appears 
  

   to 
  have 
  formed 
  part 
  of 
  a 
  long 
  wall-liko 
  mass,' 
  70 
  millim. 
  (2^ 
  inches) 
  

   high 
  and 
  15-20 
  millim. 
  thick. 
  Like 
  it, 
  it 
  is 
  surmounted 
  Ijy 
  pyra- 
  

   midal 
  processes, 
  and 
  is 
  traversed 
  from 
  the 
  upper 
  surface 
  downwards 
  

   by 
  large 
  cloacal 
  spaces. 
  Colour 
  white, 
  with 
  a 
  tinge 
  of 
  green. 
  The 
  

   spicules 
  differ 
  from 
  those 
  of 
  the 
  tjqiical 
  form 
  in 
  measuring 
  

   •9 
  by 
  '032 
  millim. 
  : 
  as, 
  however, 
  a 
  small 
  series 
  of 
  specimens 
  of 
  this 
  

   species 
  from 
  the 
  western 
  part 
  of 
  the 
  Indian 
  Ocean 
  (see 
  Part 
  II. 
  

   of 
  this 
  work) 
  includes 
  within 
  itself 
  as 
  great 
  a 
  variation 
  in 
  this 
  

   respect 
  as 
  is 
  shown 
  by 
  these 
  two 
  Australian 
  specimens, 
  I 
  do 
  not 
  

   assign 
  distinct 
  varietal 
  names 
  to 
  these 
  two, 
  at 
  first 
  sight, 
  very 
  

   distinct 
  Australian 
  specimens, 
  

  

  Hab. 
  Arafura 
  Sea, 
  32-36 
  fms. 
  ; 
  bottom 
  sand, 
  mud, 
  and 
  shells. 
  

  

  