﻿SUBDIVISIONS 
  OF 
  THE 
  SPEETON 
  CLAT. 
  609 
  

  

  Professor 
  Pavlow 
  also 
  gives 
  a 
  diagrammatic 
  view 
  of 
  the 
  equiva- 
  

   lents 
  of 
  the 
  " 
  Volga 
  beds" 
  in 
  Lincolnshire 
  and 
  the 
  South 
  of 
  England, 
  

   correlating 
  the 
  Purbeck 
  beds 
  of 
  Swindon 
  aud 
  the 
  Portland 
  stone, 
  

   and 
  also 
  the 
  Spilsby 
  Sands, 
  with 
  the 
  " 
  Upper 
  Volga 
  beds," 
  and 
  there- 
  

   fore 
  with 
  the 
  zone 
  of 
  Bel. 
  lateralis 
  at 
  Speeton. 
  M. 
  Nikitin 
  also 
  sees 
  

   in 
  the 
  Purbeck 
  beds 
  of 
  Swindon 
  the 
  freshwater 
  equivalents 
  of 
  part 
  of 
  

   the 
  " 
  Upper 
  Volga," 
  and 
  therefore 
  of 
  the 
  zone 
  of 
  Bel. 
  lateralis. 
  

  

  I 
  need 
  scarcely 
  point 
  out 
  that 
  this 
  correlation 
  of 
  the 
  Lateralis-zone 
  

   with 
  the 
  uppermost 
  beds 
  of 
  the 
  Jurassic 
  of 
  the 
  South 
  of 
  England, 
  

   made 
  before 
  it 
  was 
  known 
  that 
  this 
  zone 
  constituted 
  the 
  ' 
  Port- 
  

   laudian 
  beds 
  ' 
  of 
  Leckenby, 
  agrees 
  well 
  with 
  the 
  results 
  indepen- 
  

   dently 
  arrived 
  at 
  in 
  my 
  paper. 
  

  

  Both 
  authors 
  agree 
  in 
  recognizing 
  in 
  the 
  bituminous 
  shales 
  of 
  

   Speeton 
  (Upper 
  Kimeridge) 
  the 
  equivalents 
  of 
  the 
  "Lower 
  Volga 
  beds 
  " 
  

   of 
  Russia 
  ; 
  and 
  they 
  seem 
  to 
  desire 
  to 
  apply 
  the 
  term 
  " 
  Lower 
  Port- 
  

   landian 
  " 
  or 
  " 
  Bolonian 
  " 
  to 
  these 
  beds, 
  and 
  to 
  beds 
  of 
  similar 
  age 
  

   elsewhere 
  in 
  England, 
  thus 
  considerably 
  restricting 
  the 
  use 
  of 
  

   " 
  Kimeridgian 
  " 
  in 
  the 
  Speeton 
  section. 
  

  

  The 
  importance 
  of 
  these 
  memoirs 
  is 
  apparent, 
  and 
  they 
  are 
  almost 
  

   certain 
  to 
  lead 
  to 
  further 
  discussion. 
  

  

  The 
  papers 
  contain, 
  besides, 
  many 
  palseontological 
  observations 
  of 
  

   great 
  value, 
  in 
  which 
  the 
  fossils 
  from 
  the 
  two 
  countries 
  are 
  com- 
  

   pared. 
  In 
  a 
  few 
  instances 
  I 
  shall 
  be 
  able 
  to 
  call 
  attention 
  to 
  the 
  

   results 
  of 
  this 
  part 
  of 
  their 
  work 
  in 
  the 
  Appendix 
  to 
  this 
  paper. 
  

  

  APPENDIX. 
  

  

  Notes 
  on 
  some 
  oe 
  the 
  Possils. 
  

  

  The 
  paleontology 
  of 
  the 
  Speeton 
  Clay 
  is 
  by 
  no 
  means 
  in 
  a 
  satis- 
  

   factory 
  condition, 
  as 
  not 
  only 
  are 
  there 
  many 
  important 
  forms 
  which 
  

   have 
  not 
  yet 
  been 
  identified 
  or 
  described, 
  but 
  also 
  of 
  those 
  which 
  

   have 
  been 
  named 
  we 
  have 
  frequently 
  only 
  figures 
  of 
  doubtful 
  merit 
  

   without 
  accompanying 
  descriptions. 
  

  

  In 
  this 
  paper 
  I 
  have 
  not 
  attempted 
  to 
  compile 
  a 
  full 
  list 
  of 
  the 
  

   known 
  species 
  of 
  the 
  deposit, 
  but 
  have 
  given 
  only 
  those 
  which 
  have 
  

   been 
  identified 
  from 
  my 
  own 
  collection. 
  My 
  lists, 
  therefore, 
  should 
  

   be 
  taken 
  as 
  illustrations 
  of 
  the 
  fauna 
  rather 
  than 
  as 
  full 
  catalogues. 
  

   A 
  much 
  fuller 
  list 
  is 
  contained 
  in 
  Professor 
  Judd's 
  paper 
  ; 
  and 
  

   several 
  other 
  species 
  not 
  mentioned 
  therein 
  may 
  be 
  found 
  in 
  the 
  

   tables 
  of 
  fossils 
  in 
  Phillips's 
  ' 
  Geology 
  of 
  Yorkshire,' 
  3rd 
  ed. 
  When 
  

   the 
  task 
  of 
  thoroughly 
  working 
  up 
  the 
  fauna 
  shall 
  have 
  been 
  under- 
  

   taken 
  by 
  a 
  palaeontologist 
  conversant 
  with 
  the 
  foreign 
  equivalents 
  

   of 
  the 
  deposit, 
  a 
  rich 
  harvest 
  of 
  new 
  forms 
  and 
  of 
  forms 
  new 
  to 
  this 
  

   island 
  will 
  almost 
  certainly 
  be 
  gathered. 
  

  

  The 
  -following 
  notes 
  on 
  the 
  range 
  and 
  affinities 
  of 
  some 
  of 
  the 
  

   commoner 
  species 
  may 
  be 
  found 
  useful 
  as 
  a 
  guide 
  in 
  collecting, 
  or 
  

   for 
  comparison 
  with 
  other 
  localities. 
  

  

  2y2 
  

  

  