﻿46 
  A 
  MONOGRAPH 
  OF 
  THE 
  VICTOPJAX 
  SPONGES. 
  

  

  Particulars 
  of 
  the 
  canal 
  system 
  are 
  given 
  on 
  pp. 
  24, 
  25. 
  

  

  (b.) 
  A 
  rrangcmcnt 
  of 
  the 
  Skeleton. 
  — 
  The 
  skeleton 
  consists 
  of 
  qiiaclriradiate,triradiate 
  

   and 
  oxeote 
  spicules. 
  The 
  qiiadriradiates 
  and 
  triradiates 
  are 
  arranged 
  in 
  a 
  single 
  

   layer 
  in 
  the 
  thickness 
  of 
  the 
  mesoderm, 
  the 
  apical 
  rays 
  of 
  the 
  qnadriradiates 
  projecting 
  

   into 
  the 
  gastral 
  cavity. 
  The 
  oxeotes 
  have 
  their 
  broader 
  ends 
  embedded 
  in 
  the 
  

   mesoderm, 
  while 
  their 
  narrow 
  ends 
  project 
  outwards 
  and 
  upwards 
  through 
  the 
  

   ectoderm 
  and 
  give 
  to 
  the 
  outer 
  surfaces 
  of 
  the 
  tubes 
  their 
  hispid 
  appearance. 
  The 
  

   arrangement 
  of 
  the 
  spicules 
  is 
  shown 
  in 
  Fig. 
  1, 
  PL 
  IV. 
  

  

  (c.) 
  The 
  Spicules. 
  (PI. 
  IX., 
  Fig. 
  1). 
  

  

  (1.) 
  Triradiates. 
  — 
  These 
  are 
  sagittal, 
  but 
  the 
  three 
  angles 
  are 
  about 
  equal. 
  

   The 
  basal 
  ray 
  is 
  long 
  and 
  gradually 
  sharp-pointed, 
  measuring 
  0*1 
  mm. 
  

   in 
  length 
  by 
  0*005 
  mm. 
  in 
  diameter 
  at 
  the 
  base. 
  The 
  oral 
  rays 
  are 
  

   slightly 
  curved 
  away 
  from 
  one 
  another, 
  gradually 
  sharp-pointed, 
  

   0.07 
  mm. 
  long. 
  

  

  (2.) 
  Qnadriradiates. 
  — 
  These 
  are 
  of 
  about 
  the 
  same 
  size 
  and 
  shape 
  as 
  the 
  

   triradiates 
  with 
  the 
  addition 
  of 
  the 
  apical 
  ray, 
  which 
  is 
  shorter 
  than 
  

   the 
  others, 
  gradually 
  sharp-pointed, 
  curving 
  slightly 
  upwards 
  and 
  

   projecting 
  freely 
  into 
  the 
  gastral 
  cavity. 
  

  

  (3.) 
  Oxeotes. 
  — 
  These 
  are 
  irregularly 
  fusiform, 
  sharply 
  pointed 
  at 
  both 
  ends 
  

   but 
  broader 
  at 
  one 
  end 
  than 
  at 
  the 
  other 
  ; 
  usually 
  bent 
  suddenly 
  at 
  a 
  

   slight 
  angle 
  near 
  the 
  broader 
  end; 
  often 
  slightly 
  and 
  irregularly 
  

   curved 
  ; 
  tapering 
  gradually 
  to 
  a 
  fine 
  pomt 
  at 
  the 
  narrow 
  end 
  but 
  with 
  a 
  

   very 
  slight 
  annular 
  swelling 
  at 
  a 
  short 
  distance 
  below 
  the 
  apex. 
  They 
  

   measure 
  up 
  to 
  0-lG 
  mm. 
  in 
  length 
  by 
  0*005 
  mm. 
  in 
  diameter 
  at 
  the 
  

   broadest 
  part. 
  

  

  (d.) 
  Affinities. 
  — 
  In 
  external 
  appearance 
  this 
  species 
  resembles 
  Haeckel's 
  Soleiiiscits 
  

   variabilis* 
  but 
  it 
  differs 
  markedly 
  in 
  the 
  form 
  of 
  the 
  spicules. 
  

  

  (c.) 
  Locality.— 
  OntBide 
  Port 
  Phillip 
  Heads. 
  (Coll. 
  J. 
  B. 
  Wilson.) 
  

  

  2. 
  Leiicosolenia 
  stolonifer, 
  n. 
  sp. 
  

  

  (PI. 
  I., 
  Fig. 
  2 
  ; 
  PI. 
  VL, 
  Figs. 
  1, 
  2, 
  3 
  ; 
  PI. 
  IX., 
  Fig. 
  2.) 
  

  

  {a.) 
  General 
  Appearance 
  and 
  Canal 
  System. 
  — 
  The 
  sponge 
  (PI. 
  I., 
  Fig. 
  2) 
  

   consists 
  of 
  a 
  colony 
  of 
  Ascon-persons 
  springing 
  vertically 
  from 
  a 
  slender, 
  tubular 
  

  

  * 
  "Die 
  Kalkscbwamme," 
  Vol. 
  HI., 
  PL 
  18, 
  Fig. 
  C. 
  

  

  