﻿SPONGnDA. 
  381 
  

  

  excretory 
  chambers, 
  separated 
  by 
  comparatively 
  narrow 
  and 
  sheet- 
  

   like 
  skeletal 
  trabeculse, 
  with 
  even 
  surfaces, 
  which 
  distinguish 
  Hip- 
  

   pospomjia 
  ; 
  but 
  on 
  looking 
  at 
  the 
  brief 
  description 
  given 
  by 
  Prof. 
  F. 
  

   E. 
  Schulze 
  (Zeitsch. 
  wiss. 
  Zool. 
  xxxii. 
  p. 
  (520) 
  of 
  the 
  Adriatic 
  form 
  

   which 
  he 
  has 
  placed 
  under 
  Easponri'ia 
  ojjicinalis, 
  as 
  var. 
  tulmlosa, 
  

   I 
  saw 
  that 
  he 
  had 
  had 
  a 
  closely 
  similar 
  form 
  before 
  him. 
  It 
  agrees 
  

   with 
  our 
  specimen 
  in 
  the 
  long 
  tubes 
  (of 
  much 
  less 
  diameter, 
  how- 
  

   ever, 
  in 
  the 
  Adriatic 
  tuhulosa 
  than 
  here) 
  and 
  in 
  the 
  absence 
  of 
  sand- 
  

   cored 
  fibres 
  ; 
  but 
  it 
  appears 
  to 
  want 
  the 
  following 
  striking 
  peculi- 
  

   arities 
  of 
  our 
  form 
  : 
  — 
  (1) 
  subglobular 
  form 
  (incrusting 
  in 
  Schulze's 
  

   specimens) 
  ; 
  (2) 
  trabecular 
  structure 
  of 
  main 
  body 
  ; 
  (3) 
  absence 
  of 
  

   conuli 
  (they 
  are 
  stated 
  bj' 
  Schulze 
  to 
  occur 
  on 
  the 
  general 
  body 
  of 
  

   the 
  sponge, 
  but 
  in 
  a 
  very 
  well-preserved 
  specimen 
  in 
  absolute 
  alcohol 
  

   which 
  he 
  has 
  liberally 
  presented 
  to 
  the 
  National 
  Collection, 
  I 
  find 
  

   them 
  only 
  on 
  some 
  small 
  digitate 
  lobes 
  which 
  spring 
  from 
  the 
  body 
  ; 
  

   those 
  possibly 
  occurring 
  upon 
  one 
  of 
  the 
  tubes 
  in 
  var. 
  cavernosa 
  are 
  

   evidently 
  only 
  exceptional) 
  ; 
  (4) 
  approximate 
  equality 
  in 
  stoutness 
  

   of 
  fibres 
  throughout 
  (in 
  var. 
  tnhulosa 
  those 
  near 
  the 
  siirface 
  are 
  

   said 
  to 
  be 
  thinner 
  than 
  elsewhere). 
  

  

  In 
  a 
  preparation 
  made 
  from 
  Prof. 
  Schulze's 
  specimen 
  I 
  do 
  not 
  

   notice 
  a 
  special 
  thinness 
  of 
  the 
  fibres 
  at 
  the 
  surface, 
  but 
  thej' 
  seem 
  

   to 
  have 
  a 
  slightly 
  greater 
  diameter 
  throughout 
  than 
  in 
  our 
  form. 
  

  

  Considering 
  the 
  dry 
  state 
  of 
  this 
  single 
  specimen 
  and 
  the 
  evident 
  

   plasticity 
  of 
  form 
  in 
  E. 
  ojjicinalis, 
  I 
  think 
  it 
  best 
  to 
  associate 
  this 
  

   form 
  provisionally 
  with 
  that 
  termed 
  by 
  Prof. 
  Schulze 
  var. 
  tnhulosa, 
  

   feeling 
  that 
  it 
  may 
  be 
  only 
  a 
  mere 
  extreme 
  variation 
  of 
  the 
  species 
  

   in 
  the 
  same 
  direction 
  as 
  that 
  variety, 
  deferring 
  (as 
  I 
  feel 
  bound 
  to 
  

   do 
  on 
  a 
  question 
  which 
  Prof. 
  Schulze 
  has 
  made 
  so 
  eminently 
  his 
  

   own) 
  to 
  Prof. 
  Schulze's 
  judgment 
  in 
  specifically 
  uniting 
  aberrant 
  

   forms 
  like 
  these 
  with 
  those 
  familiarly 
  known 
  as 
  E. 
  ojjicinalis 
  ; 
  I 
  am, 
  

   however, 
  induced, 
  from 
  the 
  points 
  of 
  divergence 
  from 
  tuhulosa 
  noted 
  

   above, 
  to 
  assign 
  to 
  it 
  a 
  distinct 
  varietal 
  designation. 
  

  

  Hah. 
  Torres 
  Straits, 
  10 
  fms. 
  

  

  Distrihution 
  (of 
  species). 
  Mediterranean 
  (Schulze, 
  &c.). 
  

  

  4. 
  Euspongia 
  septosa. 
  

   ? 
  Spongia 
  septosa, 
  Lamarck, 
  Ann. 
  Mtis. 
  Hist. 
  Nat. 
  xx. 
  p. 
  373. 
  

  

  It 
  is 
  possible 
  that 
  Lamarck's 
  species, 
  of 
  which 
  I 
  have 
  access 
  to 
  

   the 
  description 
  only, 
  is 
  a 
  Dendrospomiia 
  (H5'att), 
  as 
  its 
  somewhat 
  

   honeycomb-like 
  surface 
  renders 
  not 
  impossible 
  ; 
  but 
  it 
  seems 
  to 
  

   resemble 
  a 
  species 
  in 
  this 
  collection, 
  represented 
  by 
  two 
  small 
  speci- 
  

   mens 
  in 
  spii'it, 
  of 
  a 
  dark 
  grey 
  colour, 
  each 
  attached 
  to 
  two 
  or 
  more 
  

   stones, 
  over 
  which 
  they 
  form 
  horizontally 
  expanded 
  lamina? 
  which 
  

   rise 
  into 
  subcylindrical 
  lobes 
  5 
  to 
  7 
  millim. 
  in 
  diameter. 
  The 
  surface 
  

   is 
  broken 
  up 
  by 
  a 
  number 
  of 
  sharp 
  prominent 
  ridges 
  and 
  points 
  

   1 
  to 
  3 
  millim. 
  high 
  ; 
  the 
  intermediate 
  surface 
  is 
  rough. 
  Primary 
  

   skeleton-fibres 
  set 
  approximately 
  at 
  right 
  angles 
  to 
  surfice, 
  thickness 
  

   about 
  •00 
  millim. 
  ; 
  secondaries 
  approximatelj' 
  vertical 
  to 
  primaries, 
  

   about 
  •035 
  to 
  -053 
  millim. 
  in 
  thickness, 
  forming 
  with 
  some 
  connecting 
  

  

  