﻿FROM 
  MOUNT 
  GAMBIER, 
  SOUTH 
  AUSTRALIA. 
  269 
  

  

  39. 
  Portna 
  larvalis, 
  MacGill. 
  Plate 
  VIII. 
  fig. 
  19 
  *. 
  

  

  Lepralia 
  larvalis, 
  MacGillivray, 
  Nat. 
  Hist, 
  of 
  Vict. 
  dec. 
  iv. 
  p. 
  30, 
  

   pi. 
  xxxvii. 
  fig. 
  5. 
  

  

  Zoarium 
  cylindrical, 
  foliaceous, 
  or 
  incrusting. 
  Zooecia 
  not 
  very 
  

   distinct, 
  upper 
  part 
  raised 
  ; 
  immediately 
  below 
  the 
  aperture 
  two 
  

   very 
  large 
  pores 
  ; 
  below 
  these, 
  somewhat 
  to 
  one 
  side, 
  an 
  avicularium 
  

   with 
  acute 
  or 
  elongate 
  mandible. 
  Surface 
  with 
  denticulated 
  pores. 
  

   Dorsal 
  (or 
  basal) 
  surface 
  in 
  incrusting 
  form 
  open. 
  One 
  or 
  some- 
  

   times 
  two 
  spines 
  on 
  each 
  side 
  of 
  the 
  aperture. 
  Aperture 
  (peristomial) 
  

   0-16 
  to 
  0-18 
  millim. 
  wide. 
  

  

  The 
  incrusting 
  form 
  from 
  Australia 
  is 
  one 
  of 
  the 
  most 
  beautiful 
  

   Bryozoa, 
  to 
  which 
  the 
  figure 
  of 
  MacGillivray 
  does 
  not 
  do 
  justice. 
  

   It 
  has 
  a 
  clear 
  glassy 
  shell, 
  with 
  the 
  front 
  of 
  the 
  peristome 
  much 
  

   projecting, 
  with 
  a 
  central 
  rim 
  running 
  down 
  the 
  peristome 
  ; 
  and 
  

   from 
  this 
  central 
  ridge 
  two 
  smaller 
  ones 
  are 
  given 
  off 
  to 
  surround 
  

   the 
  large 
  pores. 
  

  

  The 
  generic 
  position 
  of 
  the 
  above 
  is 
  a 
  most 
  difficult 
  question. 
  The 
  

   two 
  large 
  suboral 
  pores 
  are 
  clearly 
  important 
  structures 
  ; 
  and 
  as 
  

   they' 
  open 
  into 
  the 
  peristome 
  I 
  have 
  placed 
  it 
  with 
  the 
  Porinidse 
  ; 
  for 
  

   I 
  think 
  we 
  shall 
  probably 
  find 
  that 
  the 
  pore 
  of 
  the 
  PorinidaD 
  opens 
  

   into 
  the 
  throat, 
  while 
  the 
  pore 
  of 
  the 
  Microporellidse 
  opens 
  into 
  the 
  

   body 
  of 
  the 
  zooecium. 
  As 
  an 
  example, 
  the 
  pore 
  of 
  Porina 
  coronata 
  

   opens 
  into 
  the 
  peristome 
  above 
  the 
  operculum, 
  whereas 
  in 
  Micro- 
  

   porella 
  cenigmatica 
  (Q. 
  J. 
  G. 
  S. 
  vol. 
  xxxvii. 
  pi. 
  xv. 
  fig. 
  30) 
  it 
  is 
  in 
  the 
  

   centre 
  of 
  the 
  front 
  wall. 
  On 
  the 
  other 
  hand, 
  the 
  denticulated 
  pores 
  

   (as 
  seen 
  in 
  the 
  recent 
  specimens) 
  are 
  a 
  Microporellidan 
  character. 
  

  

  If 
  this 
  is 
  united 
  to 
  Porina, 
  the 
  definition 
  of 
  the 
  genus 
  must 
  be 
  

   somewhat 
  extended 
  ; 
  and 
  the 
  same 
  change 
  has 
  been 
  made 
  with 
  the 
  

   Microporellidae, 
  which 
  Mr. 
  Hincks 
  described 
  as 
  with 
  " 
  a 
  semilunate 
  

   or 
  circular 
  pore 
  on 
  the 
  front 
  wall," 
  whereas 
  I 
  think 
  we 
  may 
  say 
  

   that 
  in 
  both 
  families 
  there 
  may 
  be 
  more 
  than 
  one 
  pore. 
  

  

  Log. 
  Living 
  : 
  Williamstown 
  (Victoria, 
  McG.) 
  ; 
  Bondi 
  Bay, 
  New 
  

   South 
  Wales 
  (A. 
  W. 
  PP.), 
  and 
  Semaphore, 
  Adelaide 
  {A. 
  W. 
  W.). 
  

   Fossil 
  : 
  Bairnsdale. 
  

  

  I 
  have 
  also 
  seen 
  it 
  in 
  the 
  British 
  Museum 
  among 
  undescribed 
  

   material 
  from 
  the 
  southern 
  hemisphere. 
  

  

  40. 
  Lepralia 
  spatula 
  ta, 
  Waters. 
  

  

  Lepralia 
  spatulata, 
  Waters, 
  loc. 
  cit. 
  p. 
  335, 
  pi. 
  xviii. 
  fig. 
  87. 
  

  

  The 
  large 
  spatulate 
  avicularia 
  scattered 
  between 
  the 
  zooecia 
  are 
  

   sometimes 
  nearly 
  as 
  long 
  as 
  a 
  zocecium. 
  

  

  41. 
  Lepralia 
  foltacea, 
  Ell. 
  & 
  Sol. 
  Plate 
  VII. 
  fig. 
  3. 
  

   For 
  synonyms 
  see 
  Hincks, 
  Brit. 
  Mar. 
  Polyz. 
  p. 
  300. 
  

  

  The 
  position 
  of 
  the 
  avicularium 
  seems 
  to 
  vary, 
  from 
  being 
  entirely 
  

   in 
  the 
  mouth, 
  to 
  being 
  placed 
  some 
  little 
  distance 
  down 
  at 
  one 
  side, 
  

  

  * 
  I 
  am 
  sorry 
  that 
  the 
  lithographer 
  has 
  been 
  very 
  unsucessful 
  with 
  this 
  

   figure. 
  The 
  aperture 
  should 
  have 
  been 
  shown 
  more 
  regular 
  and 
  without 
  the 
  

   wide 
  denticle 
  figured. 
  

  

  