﻿FROM 
  MOUNT 
  GAMBIEB, 
  SOUTH 
  AUSTRALIA. 
  263 
  

  

  and 
  also 
  " 
  Contr. 
  towards 
  a 
  Gen. 
  Hist, 
  of 
  the 
  Mar. 
  Poly." 
  p. 
  53, 
  

   pi. 
  ii. 
  figs. 
  6, 
  6 
  a, 
  6 
  b, 
  Ann. 
  & 
  Mag. 
  Nat. 
  Hist. 
  s. 
  5, 
  vol. 
  viii. 
  pi. 
  ii. 
  

  

  In 
  the 
  fossil 
  specimens 
  the 
  shape 
  of 
  the 
  area 
  is 
  very 
  irregular, 
  

   often 
  very 
  elongate. 
  The 
  remains 
  of 
  the 
  two 
  spines 
  are 
  clearly 
  to 
  

   be 
  seen, 
  as 
  also 
  the 
  basis 
  of 
  the 
  forked 
  spine 
  and 
  avicularium 
  ; 
  and 
  

   on 
  the 
  dorsal 
  surface 
  there 
  are 
  six 
  depressions 
  round 
  each 
  zooecium. 
  

   Ocecium 
  globose. 
  Surface 
  apparently 
  with 
  elongate 
  pores 
  ; 
  but, 
  from 
  

   the 
  state 
  of 
  fossilization, 
  it 
  is 
  impossible 
  to 
  be 
  sure 
  about 
  this 
  point. 
  

   On 
  each 
  of 
  the 
  six 
  lateral 
  walls 
  a 
  large, 
  elongate, 
  oval 
  opening, 
  re- 
  

   presenting 
  the 
  rosette-plate. 
  Area 
  of 
  average 
  cells 
  0*46 
  millim. 
  

   long, 
  0*25 
  wide. 
  

  

  Loc. 
  Living 
  : 
  Bass's 
  Straits. 
  

  

  17. 
  Membkanipoka 
  dentata, 
  d'Orb. 
  Plate 
  VIII. 
  fig. 
  14. 
  

  

  Flustrellaria 
  dentata, 
  d'Orb. 
  Pal. 
  Prang, 
  p. 
  525, 
  pi. 
  725. 
  figs. 
  

   17-21. 
  

  

  Membranipora 
  annulns, 
  Manzoni, 
  Bry. 
  foss. 
  Ital. 
  4ta 
  cont. 
  p. 
  7, 
  

   pi. 
  i. 
  fig. 
  9 
  ; 
  Manzoni, 
  I 
  Briozoi 
  di 
  Castrocaro, 
  p. 
  12, 
  pi. 
  i. 
  fig. 
  9. 
  

  

  Zoarium 
  incrusting. 
  Zooecia 
  much 
  raised 
  at 
  the 
  distal 
  end, 
  with 
  

   four 
  large 
  spines 
  on 
  the 
  front 
  of 
  the 
  cell 
  and 
  one 
  or 
  two 
  large 
  central 
  

   ones 
  at 
  the 
  extreme 
  end 
  at 
  a 
  rather 
  lower 
  level, 
  often 
  directed 
  for- 
  

   wards. 
  Aperture 
  round 
  or 
  oval, 
  nearly 
  the 
  length 
  of 
  the 
  zooecium. 
  

   Ovicell 
  Jarge, 
  the 
  width 
  of 
  a 
  zooecium. 
  The 
  aperture 
  is 
  about 
  

   0*23 
  millim. 
  wide. 
  

  

  In 
  d'Orbigny's 
  figure 
  the 
  spines 
  are 
  not 
  so 
  much 
  forward; 
  but 
  

   otherwise 
  there 
  seems 
  to 
  be 
  no 
  difference. 
  Specimens 
  in 
  my 
  posses- 
  

   sion 
  from 
  the 
  Pliocene 
  of 
  Bametto 
  (Sicily) 
  correspond 
  in 
  every 
  parti- 
  

   cular 
  with 
  those 
  from 
  Mt. 
  Gambier. 
  I 
  have 
  had 
  a 
  Bryozoan 
  colony 
  

   sent 
  me 
  from 
  New 
  Zealand, 
  marked 
  M 
  . 
  ciliata, 
  MacGillivray 
  ; 
  and 
  

   although 
  MacGillivray's 
  figure 
  leaves 
  determination 
  very 
  difficult, 
  yet 
  

   from 
  the 
  description 
  I 
  think 
  my 
  specimen 
  is 
  correctly 
  determined. 
  

   In 
  this 
  the 
  distal 
  end 
  is 
  not 
  so 
  much 
  raised, 
  and 
  the 
  central 
  spine 
  

   is 
  not 
  larger 
  than 
  the 
  others, 
  nor 
  is 
  the 
  aperture 
  quite 
  so 
  long; 
  

   but 
  I 
  think 
  it 
  must 
  be 
  looked 
  upon 
  as 
  an 
  ally. 
  

  

  Log. 
  Cretaceous, 
  Sainte 
  Colombe 
  (Manche), 
  Senonian 
  ; 
  Pliocene, 
  

   Castelarquato, 
  Parlascio, 
  Orciano 
  {Manx.) 
  ; 
  in 
  the 
  province 
  of 
  Beggio, 
  

   Calabria, 
  it 
  occurs 
  in 
  the 
  Helvetian, 
  Zanclian, 
  Astian, 
  and 
  Sicilian 
  

   beds 
  (Seguenza), 
  Bametto 
  (A. 
  W. 
  W. 
  coll.). 
  

  

  18. 
  Membeanhpoka 
  cylindbifoemis, 
  Waters. 
  Plate 
  VIII. 
  fig. 
  13. 
  

   Membranipora 
  cylindriformis, 
  Waters, 
  loc. 
  cit. 
  p. 
  323, 
  pi. 
  xvii. 
  

  

  %. 
  74. 
  

  

  In 
  the 
  Mount 
  Gambier 
  and 
  Bairnsdale 
  specimens 
  the 
  cells 
  are 
  

   nearer 
  together, 
  so 
  that 
  there 
  is 
  frequently 
  hardly 
  any 
  space 
  between 
  

   the 
  areas. 
  The 
  small 
  avicularium 
  above 
  the 
  area 
  is 
  usually 
  absent 
  ; 
  

   and 
  the 
  [suboral 
  avicularium 
  is 
  frequently 
  much 
  raised 
  at 
  right 
  

   angles 
  to 
  the 
  axis 
  of 
  the 
  zoarium, 
  and 
  is 
  sometimes 
  quite 
  within 
  the 
  

   area 
  ; 
  and 
  we 
  are 
  then 
  reminded 
  of 
  Membranipora 
  minax. 
  Aperture 
  

   about 
  0*20 
  millim. 
  wide. 
  

  

  Loc. 
  S.W. 
  Victoria 
  and 
  Bairnsdale. 
  

  

  t2 
  

  

  