﻿96 
  ME. 
  E. 
  K. 
  COWPEK 
  EEED 
  OIST 
  THE 
  [Feb. 
  1 
  897,. 
  

  

  The 
  possession 
  of 
  so 
  many 
  peculiar 
  forms 
  stamps 
  the 
  fauna 
  with 
  a 
  

   distinct 
  individuality 
  and 
  strongly 
  differentiates 
  it 
  from 
  all 
  other 
  

   British 
  beds. 
  

  

  Summing 
  up, 
  therefore, 
  the 
  palseontological 
  evidence 
  with 
  re- 
  

   ference 
  to 
  its 
  stratigraphical 
  position, 
  we 
  find 
  : 
  (1) 
  that 
  the 
  fauna 
  

   has 
  a 
  thoroughly 
  Ordovician 
  facies 
  ; 
  (2) 
  that 
  it 
  possesses 
  a 
  large 
  

   number 
  of 
  peculiar 
  species 
  ; 
  (3) 
  that 
  while 
  possessing 
  a 
  considerable 
  

   number 
  of 
  Middle 
  Bala 
  species, 
  yet 
  the 
  presence 
  of 
  certain 
  forms 
  

   known 
  elsewhere 
  only 
  from 
  or 
  only 
  commencing 
  in 
  the 
  Upper 
  

   Bala 
  Beds 
  points 
  to 
  a 
  closer 
  relationship 
  to 
  the 
  latter 
  than 
  to 
  the 
  

   Middle 
  Bala 
  ; 
  (4) 
  that 
  the 
  affinity 
  of 
  the 
  fauna 
  is 
  much 
  closer 
  with 
  

   that 
  of 
  the 
  Staurocephalus-zone 
  than 
  with 
  that 
  of 
  the 
  overlying 
  

   Ashgill 
  Shales 
  ; 
  (5) 
  that 
  the 
  presence 
  of 
  so 
  many 
  peculiar 
  forms, 
  as 
  

   well 
  as 
  the 
  absence 
  of 
  certain 
  typical 
  species 
  of 
  the 
  Staurocephalus- 
  

   zone, 
  precludes 
  us 
  from 
  considering 
  the 
  Keisley 
  Limestone 
  and 
  

   Staurocephalus-zone 
  to 
  be 
  on 
  exactly 
  the 
  same 
  horizon, 
  while 
  the 
  

   presence 
  of 
  a 
  number 
  of 
  Middle 
  Bala 
  forms 
  inclines 
  us 
  to 
  put 
  the 
  

   Keisley 
  Limestone 
  slightly 
  below 
  rather 
  than 
  above 
  the 
  Stauro- 
  

   cephalus-zone. 
  

  

  Thus 
  it 
  is 
  at 
  the 
  bottom 
  of 
  the 
  Upper 
  Bala 
  that 
  on 
  the 
  strength 
  

   of 
  the 
  palaeontological 
  evidence 
  I 
  would 
  put 
  the 
  Keisley 
  Limestone, 
  

   Mr. 
  Marr 
  has 
  arrived 
  at 
  nearly 
  the 
  same 
  conclusion, 
  1 
  for 
  he 
  says 
  

   that 
  its 
  fauna 
  distinctly 
  belongs 
  to 
  a 
  lower 
  horizon 
  than 
  the 
  Ashgill 
  

   Shales, 
  and 
  he 
  would 
  place 
  it 
  immediately 
  below 
  the 
  Staurocephalus- 
  

   Limestone 
  as 
  the 
  uppermost 
  bed 
  of 
  the 
  Applethwaite 
  Beds 
  of 
  the 
  

   Sleddale 
  Group 
  of 
  the 
  Coniston 
  Limestone 
  Series, 
  that 
  is, 
  at 
  the 
  top 
  

   of 
  the 
  Middle 
  Bala. 
  

  

  Sedgwick 
  and 
  Salter 
  2 
  assigned 
  the 
  fossils 
  from 
  this 
  bed 
  to 
  the 
  

   Middle 
  Bala 
  group. 
  

  

  Ieish 
  and 
  Continental 
  Equivalents. 
  

  

  Throughout 
  the 
  preceding 
  description 
  of 
  the 
  fauna 
  of 
  the 
  Keisley 
  

   Limestone 
  frequent 
  reference 
  has 
  been 
  made 
  to 
  the 
  Chair 
  of 
  

   Kildare 
  Limestone, 
  the 
  Leptcena-Limestone 
  of 
  Dalecarlia, 
  and 
  the 
  

   Borkholm 
  and 
  Lyckholm 
  zones, 
  which 
  constitute 
  Schmidt's 
  Stage 
  F 
  

   of 
  the 
  East 
  Baltic 
  provinces 
  of 
  Bussia, 
  and 
  many 
  of 
  the 
  Keisley 
  

   species 
  have 
  been 
  mentioned 
  as 
  occurring 
  in 
  one 
  or 
  more 
  of 
  these 
  beds. 
  

   A 
  brief 
  summary 
  of 
  the 
  common 
  species 
  will 
  bring 
  out 
  the 
  close 
  

   relationship 
  of 
  these 
  beds 
  clearly. 
  Unfortunately, 
  only 
  in 
  the 
  case 
  

   of 
  the 
  Kildare 
  and 
  Leptcena 
  Limestones 
  has 
  the 
  fauna 
  been 
  to 
  any 
  

   extent 
  adequately 
  worked 
  out, 
  and 
  even 
  in 
  these 
  two 
  cases 
  there 
  is 
  

   room 
  for 
  a 
  further 
  scrutiny. 
  The 
  lists 
  of 
  fossils 
  from 
  the 
  Borkholm 
  

   and 
  Lyckholm 
  beds 
  are 
  very 
  meagre. 
  Schmidt, 
  3 
  however, 
  states 
  

   that 
  the 
  Swedish 
  Leptcena-Limestone 
  of 
  the 
  Osmundsberg 
  in 
  Dalarne 
  

   which 
  he 
  visited 
  seems 
  perfectly 
  identical 
  with 
  the 
  white 
  Bork- 
  

  

  i 
  Geol. 
  Mag. 
  1892, 
  pp. 
  97 
  & 
  445. 
  

  

  2 
  Cat. 
  Cambr. 
  & 
  Sil. 
  Foss. 
  Woodw. 
  Mus. 
  (1873) 
  p. 
  54, 
  etc. 
  

  

  3 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xxxviii. 
  (1882) 
  p. 
  514 
  ; 
  [quoted 
  by 
  Linnarsson], 
  

   Zeitschr. 
  d. 
  Deutsch. 
  geol. 
  Gesellsch. 
  vol. 
  xxv. 
  (1873) 
  pp. 
  696-697. 
  

  

  