﻿100 
  PKOCKEDINGS 
  OF 
  THE 
  MALACOLOGICAL 
  SOCIE'lT. 
  

  

  Plaxiphora 
  costata 
  (Blainville). 
  Sjiecimens 
  from 
  Queensland, 
  

   Tasmania, 
  and 
  South 
  Australia. 
  

  

  Plaxiphora 
  albida 
  (Ulaiiiville). 
  New 
  South 
  Wales, 
  Victoria, 
  Soutli 
  

   Australia, 
  and 
  Tasmania. 
  

  

  Plaxipho7-a 
  2)ceteliana, 
  Thiele. 
  New 
  South 
  Wales. 
  

  

  Plaxiphora 
  matthetvsi, 
  Iredale. 
  South 
  Australia. 
  

  

  It 
  was 
  obvious 
  from 
  that 
  paper 
  tliat 
  no 
  definite 
  result 
  had 
  been 
  

   achieved, 
  and 
  other 
  workers 
  found 
  great 
  difficulty 
  in 
  accepting 
  these 
  

   conclusions. 
  The 
  writer 
  was 
  just 
  as 
  dissatisfied, 
  and 
  later 
  recorded 
  

   that 
  he 
  was 
  still 
  working 
  on 
  the 
  matter. 
  Herein 
  is 
  presented 
  a 
  reason 
  

   for 
  reconsidering 
  the 
  whole 
  subject, 
  bnt 
  material 
  is 
  demanded. 
  

  

  It 
  has 
  been 
  abundantly 
  proved 
  by 
  the 
  large 
  collections 
  now 
  

   available 
  that 
  all 
  Chitons 
  are 
  very 
  local 
  in 
  their 
  distribution, 
  and 
  

   this 
  suggests 
  the 
  criticism 
  of 
  series 
  from 
  definite 
  localities. 
  With 
  

   such 
  series 
  field 
  notes 
  should 
  be 
  considered 
  and 
  the 
  variation 
  

   established. 
  Thus 
  " 
  Tasmania" 
  is 
  of 
  little 
  use 
  as 
  a 
  locality 
  Avhen 
  we 
  

   know 
  the 
  northern 
  shells 
  may 
  differ 
  from 
  the 
  southern, 
  and 
  from 
  the 
  

   south 
  alone 
  we 
  seem 
  to 
  have 
  three 
  distinct 
  species, 
  not 
  counting 
  

   matthewsi, 
  Iredale, 
  which 
  is 
  not 
  a 
  Plaxiphora, 
  strictly 
  speaking, 
  at 
  all. 
  

  

  Tasmanian 
  shells 
  have 
  been 
  twice 
  named, 
  thus 
  : 
  P. 
  albida 
  (Blain- 
  

   ville), 
  King 
  Island; 
  P. 
  tasmanica, 
  Thiele, 
  new 
  name 
  for 
  Chiton 
  

   fflaucus, 
  Q,uoy 
  & 
  Gaimard, 
  from 
  southern 
  Tasmania. 
  

  

  We 
  have 
  not 
  yet 
  examined 
  actual 
  topotypes, 
  but 
  Thiele 
  has 
  given 
  

   figures 
  of 
  tlie 
  type 
  of 
  the 
  first-named, 
  and 
  good 
  figures 
  were 
  given 
  by 
  

   Quoy 
  & 
  Gaimard 
  as 
  well 
  as 
  by 
  Thiele 
  of 
  the 
  other. 
  As 
  previously 
  

   stated, 
  it 
  is 
  hoped 
  to 
  settle 
  this 
  matter 
  in 
  detail 
  later, 
  but 
  we 
  call 
  

   attention 
  to 
  it 
  in 
  the 
  hopes 
  of 
  obtaining 
  further 
  co-operation, 
  many 
  

   more 
  specimens 
  being 
  necessary. 
  Thus 
  Torr 
  has 
  sent 
  us 
  shells 
  from 
  

   St. 
  Francis 
  Island 
  which 
  he 
  has 
  called 
  costata, 
  publishing 
  a 
  note, 
  

   " 
  Mr. 
  Gatliffe, 
  of 
  Victoria, 
  identifies 
  this 
  shell 
  with 
  P. 
  bednalli, 
  

   Thiele." 
  We 
  are 
  inclined 
  to 
  agree 
  with 
  Gatliff, 
  and 
  the 
  shells 
  are 
  

   certainly 
  not 
  costata 
  (Blainville). 
  Toit 
  also 
  sent 
  us 
  a 
  topotype 
  of 
  the 
  

   latter, 
  and 
  it 
  seems 
  distinct 
  from 
  the 
  South 
  Australian 
  shell 
  we 
  had 
  so 
  

   identified. 
  Further, 
  South 
  Australian 
  shells 
  do 
  not 
  seem 
  to 
  agree 
  

   with 
  Tasmanian 
  shells 
  determined 
  as 
  albida 
  (Blainville), 
  so 
  that 
  

   probably 
  the 
  former 
  will 
  bear 
  the 
  name 
  of 
  conspersa, 
  Adams 
  & 
  Angas. 
  

   A 
  further 
  complication 
  exists 
  in 
  Plaxiphora 
  pa;teliana, 
  Thiele. 
  This 
  

   was 
  described 
  as 
  from 
  "Tasmania", 
  and 
  Iredale, 
  probably 
  wrongly 
  

   so 
  determined 
  a 
  New 
  South 
  Wales 
  species. 
  

  

  The 
  items 
  calling 
  for 
  urgent 
  solution 
  are: 
  Does 
  P. 
  albida 
  

   (Blainville) 
  exist 
  in 
  South 
  Australia, 
  and, 
  if 
  so, 
  is 
  P. 
  conspersa, 
  

   Adams 
  & 
  Angas, 
  synonymous? 
  Does 
  P. 
  costata 
  (Blainville) 
  range 
  

   into 
  South 
  Australia 
  and 
  Tasmania, 
  or 
  is 
  it 
  represented 
  by 
  different 
  

   forms 
  ? 
  Does 
  P. 
  bednalli, 
  Thiele, 
  range 
  into 
  West 
  Australia, 
  and, 
  if 
  so, 
  

   is 
  not 
  P. 
  hedlei/i, 
  Torr, 
  the 
  immature 
  shell, 
  and 
  also 
  isnot 
  this 
  the 
  form 
  

   recorded 
  as 
  P. 
  albida 
  (Blainville) 
  by 
  Thiele 
  ? 
  Again, 
  does 
  P. 
  bednalli, 
  

   Thiele, 
  range 
  into 
  Tasmania 
  or 
  is 
  it 
  there 
  represented 
  by 
  a 
  closelj' 
  

   allied 
  form 
  ? 
  These 
  questions 
  can 
  only 
  be 
  answered 
  by 
  the 
  study 
  of 
  

   systematically 
  made 
  collections 
  of 
  numbers 
  with 
  field 
  notes. 
  This 
  is 
  

   necessary, 
  as 
  it 
  is 
  quite 
  impossible 
  to 
  gauge 
  the 
  merits 
  of 
  the 
  cases 
  by 
  

  

  