﻿PR. 
  G. 
  J. 
  HINDE 
  ON 
  ARCHJEOCTATHUS 
  AND 
  OTHER 
  GENERA. 
  125 
  

  

  8. 
  On 
  ARCHiEOCYATHtrs, 
  Billing 
  s, 
  and 
  on 
  other 
  Genera, 
  allied 
  to 
  

   or 
  associated 
  ivith 
  it, 
  from 
  the 
  Cambrian 
  Strata 
  of 
  North 
  

   America, 
  Spain, 
  Sardinia, 
  and 
  Scotland. 
  By 
  George 
  Jennings 
  

   Hinde, 
  Ph.D., 
  F.G.S. 
  (Read 
  December 
  19, 
  1888.) 
  

  

  [Plate 
  V.] 
  

  

  The 
  real 
  characters 
  and 
  the 
  relations 
  of 
  the 
  group 
  of 
  fossils 
  known 
  

   generally 
  under 
  the 
  term 
  Archmocyathus 
  are 
  at 
  present 
  subjects 
  of 
  

   discussion 
  among 
  palaeontologists 
  ; 
  they 
  have 
  been 
  regarded 
  as 
  allied 
  

   to 
  Foraminifera, 
  Sponges, 
  and 
  Corals. 
  Many 
  of 
  the 
  forms 
  occur 
  

   in 
  the 
  lowest 
  fossiliferous 
  zones 
  of 
  the 
  Cambrian 
  rocks, 
  and 
  are 
  thus 
  

   among 
  the 
  earliest 
  known 
  forms 
  of 
  life, 
  a 
  fact 
  which 
  gives 
  addi- 
  

   tional 
  interest 
  to 
  their 
  study. 
  Since 
  Mr. 
  Billings 
  first 
  called 
  

   attention 
  to 
  them 
  in 
  1861, 
  they 
  have 
  been 
  investigated 
  by 
  several 
  

   authors, 
  more 
  particularly 
  by 
  Sir 
  J. 
  W. 
  Dawson, 
  Prof. 
  Ferd. 
  Homer, 
  

   Mr. 
  C. 
  D. 
  Walcott, 
  and, 
  more 
  recently, 
  by 
  Dr. 
  Bornemann 
  ; 
  but 
  it 
  

   cannot 
  be 
  said 
  that 
  the 
  obscurity 
  attaching 
  to 
  them 
  has 
  been 
  fully 
  

   cleared 
  up. 
  I 
  have 
  been 
  induced 
  by 
  Sir 
  J. 
  W. 
  Dawson 
  to 
  under- 
  

   take 
  an 
  independent 
  investigation 
  of 
  their 
  characters, 
  based 
  more 
  

   particularly 
  on 
  their 
  microscopic 
  structure, 
  and, 
  thanks 
  to 
  the 
  kind- 
  

   ness 
  of 
  the 
  above-named 
  authors, 
  I 
  have 
  been 
  supplied 
  with 
  material 
  

   which 
  has 
  enabled 
  me 
  to 
  ascertain 
  by 
  direct 
  comparison 
  the 
  nature 
  

   of 
  these 
  fossils 
  from 
  widely 
  separated 
  localities. 
  Thus 
  Sir 
  J. 
  W. 
  

   Dawson 
  sent 
  some 
  specimens 
  from 
  Labrador 
  belonging 
  to 
  McGill 
  

   College 
  Museum 
  ; 
  the 
  Geological 
  Survey 
  of 
  Canada, 
  through 
  Mr. 
  

   J. 
  F. 
  Whiteaves, 
  F.G 
  S., 
  supplied 
  me 
  with 
  the 
  type 
  forms 
  described 
  

   by 
  the 
  late 
  Mr. 
  Billings 
  ; 
  Prof. 
  Ferd. 
  Eomer 
  with 
  the 
  figured 
  speci- 
  

   mens 
  of 
  Archceocyathus 
  marianus 
  from 
  Spain 
  ; 
  and 
  to 
  Dr. 
  J. 
  G. 
  Bor- 
  

   nemann 
  I 
  am 
  indebted 
  for 
  fragments 
  of 
  rock 
  filled 
  with 
  these 
  fossils, 
  

   which 
  he 
  collected 
  in 
  the 
  Island 
  of 
  Sardinia 
  *. 
  

  

  The 
  microscopic 
  sections 
  which 
  I 
  have 
  prepared 
  from 
  these 
  speci- 
  

   mens 
  show 
  tha 
  tthe 
  organisms 
  originally 
  included 
  in 
  Archmocyathus 
  

   vary 
  considerably 
  in 
  structure, 
  and 
  cannot 
  properly 
  be 
  included 
  in 
  

   a 
  single 
  genus, 
  and 
  it 
  is 
  owing 
  to 
  this 
  fact 
  that 
  much 
  of 
  the 
  uncer- 
  

   tainty 
  respecting 
  the 
  real 
  nature 
  of 
  the 
  genus 
  has 
  arisen. 
  With 
  the 
  

   view 
  of 
  clearing 
  up 
  the 
  subject, 
  I 
  have 
  in 
  this 
  paper 
  described, 
  in 
  con- 
  

   siderable 
  detail, 
  the 
  microscopic 
  and 
  other 
  features 
  of 
  the 
  different 
  

   species 
  originally 
  referred 
  to 
  Archceocyathus, 
  as 
  well 
  as 
  of 
  other 
  

   forms 
  which 
  have 
  been 
  considered 
  to 
  be 
  allied 
  to 
  it 
  ; 
  I 
  have 
  removed 
  

   from 
  the 
  genus, 
  and 
  placed 
  in 
  other 
  genera, 
  the 
  forms 
  which 
  

   do 
  not 
  generically 
  correspond 
  in 
  structure 
  with 
  its 
  type 
  species, 
  and 
  I 
  

   have 
  discussed 
  the 
  relationship 
  of 
  these 
  different 
  fossils 
  to 
  Corals 
  and 
  

   Sponges 
  respectively. 
  

  

  * 
  Since 
  this 
  paper 
  was 
  read 
  before 
  the 
  Society, 
  Mr. 
  C. 
  D. 
  Walcott 
  has 
  kindly 
  

   sent 
  me 
  specimens 
  of 
  Ethnophyllum, 
  Meek, 
  from 
  Nevada, 
  and 
  of 
  Coscinocyathus 
  

   Billingsi, 
  Walcott, 
  from 
  Labrador. 
  — 
  (G-. 
  J. 
  H., 
  Jan. 
  24, 
  1889.) 
  

  

  