﻿58 
  A 
  MONOGEAPH 
  OF 
  THE 
  VICTOBIAN 
  SPONGES. 
  

  

  I 
  have 
  already 
  indicated 
  the 
  possible 
  identity 
  of 
  Lcucosolcnia 
  cavata 
  with 
  

   L. 
  dtcbia 
  in 
  the 
  description 
  of 
  the 
  latter. 
  The 
  species 
  is 
  common 
  near 
  Port 
  Phillip 
  

   Heads. 
  

  

  (e.) 
  Locality.— 
  ^eav 
  Port 
  Phillip 
  Heads. 
  (Coll. 
  J. 
  B. 
  Wilson.) 
  

  

  9. 
  Lcucosolcnia 
  protogcnes, 
  Hasckel 
  sp. 
  

   (PI. 
  m., 
  Fig. 
  1 
  ; 
  PI. 
  XL, 
  Fig. 
  1.) 
  

   Ascetta 
  priiiioniialis, 
  var. 
  protogcnes, 
  Hasckel. 
  "Die 
  Kalkschwamme," 
  Vol. 
  

  

  n., 
  p. 
  17. 
  

  

  Ascetta 
  procunibcns, 
  von 
  Lendenfeld. 
  Proceedings 
  of 
  the 
  Linnean 
  Society 
  of 
  New- 
  

   South 
  Wales, 
  Vol. 
  IX., 
  Part 
  4, 
  p. 
  1086. 
  

  

  ClatJirina 
  priniovdialis, 
  Carter, 
  Annals 
  and 
  Magazine 
  of 
  Natural 
  History, 
  June, 
  

   1886, 
  p. 
  510. 
  

  

  {a.) 
  General 
  Appearance 
  and 
  Canal 
  System. 
  — 
  The 
  colony 
  (PI. 
  III., 
  Fig. 
  1) 
  forms 
  

   large, 
  irregularly 
  rounded, 
  lobose 
  masses, 
  sometimes 
  attaining 
  a 
  diameter 
  of 
  as 
  much 
  

   as 
  125 
  nmi. 
  and 
  attached 
  by 
  the 
  lower 
  surface 
  to 
  the 
  substratum. 
  The 
  texture 
  of 
  the 
  

   colony 
  is 
  characteristically 
  soft, 
  spongy 
  and 
  friable. 
  The 
  surface 
  of 
  the 
  colony 
  is 
  thrown 
  

   into 
  strong, 
  irregular, 
  rounded 
  ridges 
  and 
  depressions. 
  The 
  pseudopores 
  are 
  much 
  

   more 
  abundant 
  in 
  the 
  depressed 
  portions 
  of 
  the 
  surface 
  than 
  on 
  the 
  ridges, 
  where 
  

   the 
  outer 
  skin 
  (pseudoderm) 
  is 
  better 
  developed 
  ; 
  they 
  are 
  irregularly 
  rounded 
  or 
  oval 
  

   in 
  shape 
  and 
  measure 
  about 
  1 
  mm. 
  in 
  maximum 
  diameter. 
  On 
  the 
  upper 
  surface 
  of 
  

   the 
  colony 
  are 
  numerous 
  large 
  circular 
  pseudoscula, 
  arranged 
  along 
  the 
  tops 
  of 
  the 
  

   ridges 
  and 
  each 
  with 
  a 
  rather 
  feebly 
  developed 
  membranous 
  collar 
  surrounding 
  it. 
  The 
  

   pseudoscula 
  measure 
  about 
  6 
  mm. 
  in 
  diameter 
  and 
  lead 
  each 
  into 
  a 
  distinct, 
  tubular 
  

   pseudogaster 
  which 
  penetrates 
  deeply 
  into 
  the 
  substance 
  of 
  the 
  colony. 
  The 
  colour 
  

   in 
  spirit 
  is 
  nearly 
  white. 
  

  

  The 
  canal 
  system 
  conforms 
  to 
  type 
  D, 
  and 
  hence 
  agrees 
  with 
  that 
  of 
  Leiicosolenia 
  

   ventricosa, 
  which 
  will 
  be 
  found 
  described 
  on 
  pp. 
  30, 
  31, 
  and 
  illustrated 
  in 
  Figure 
  4, 
  

   Plate 
  IV. 
  

  

  (b.) 
  Arrangement 
  of 
  the 
  Skeleton. 
  — 
  The 
  skeleton 
  consists 
  of 
  triradiate 
  spicules 
  

   only, 
  and 
  these 
  are 
  arranged 
  in 
  the 
  normal 
  manner 
  ; 
  in 
  a 
  dense, 
  confused 
  layer, 
  with 
  

   freely 
  overlapping 
  rays 
  in 
  the 
  pseudoderm, 
  and 
  less 
  densely 
  packed 
  in 
  the 
  walls 
  of 
  the 
  

   internal 
  Ascon-tubes. 
  

  

  