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  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  strata 
  that 
  can 
  be 
  coordinated 
  with 
  the 
  deposits 
  commencing 
  with 
  

   the 
  Muschelkalk, 
  which 
  in 
  time, 
  though 
  not 
  in 
  condition, 
  paralleled 
  

   our 
  Bunter 
  and 
  Keuper 
  deposits. 
  These 
  thick 
  strata, 
  either 
  of 
  

   freshwater 
  or 
  marine 
  origin 
  and 
  almost 
  devoid 
  of 
  life, 
  stand 
  alone. 
  

   Their 
  final 
  close 
  through 
  elevation 
  within 
  the 
  British 
  area 
  gave 
  us 
  

   a 
  series 
  of 
  deposits 
  known 
  as 
  the 
  Bhaetic 
  series 
  of 
  Middle 
  and 
  

   Eastern 
  Europe. 
  Continental 
  changes 
  alone 
  can 
  only 
  account 
  for 
  

   our 
  not 
  possessing 
  the 
  Muschelkalk, 
  the 
  St.-Cassian 
  or 
  Hallstatt 
  

   beds, 
  the 
  Dachstein, 
  Kossen 
  or 
  Upper 
  St.-Cassian 
  beds 
  of 
  Switzer- 
  

   land, 
  and 
  other 
  groups 
  occurring 
  in 
  the 
  typical 
  area 
  of 
  Europe. 
  

  

  The 
  nature 
  of 
  the 
  fauna 
  is 
  suggestive 
  of 
  geographical 
  rather 
  than 
  

   climatal 
  changes, 
  the 
  species 
  being 
  developed 
  either 
  in 
  shallow, 
  

   cstuarine, 
  or 
  brackish 
  waters, 
  consequently 
  dwarfed 
  and 
  stunted 
  

   in 
  growth 
  ; 
  and 
  although 
  we 
  possess 
  many 
  of 
  the 
  European 
  forms, 
  

   there 
  is 
  yet, 
  in 
  those 
  regions 
  where 
  the 
  series 
  are 
  fully 
  developed, 
  a 
  

   fauna 
  the 
  magnitude 
  of 
  which 
  is 
  nearly 
  unequalled 
  by 
  any 
  British 
  

   deposit. 
  

  

  No 
  less 
  than 
  281 
  genera 
  and 
  1830 
  species 
  are 
  known 
  to 
  occur 
  in 
  

   the 
  whole 
  of 
  the 
  three 
  divisions 
  of 
  the 
  Lias 
  of 
  Great 
  Britain 
  and 
  

   Ireland. 
  These 
  extend 
  through 
  16 
  classes, 
  not 
  including 
  the 
  kingdom 
  

   Plantao, 
  which 
  is 
  represented 
  in 
  the 
  Lias 
  by 
  12 
  genera 
  and 
  17 
  species, 
  

   11 
  genera 
  and 
  15 
  species 
  occurring 
  in 
  the 
  Lower 
  Lias, 
  and 
  1 
  genus 
  

   and 
  2 
  species 
  (Pence 
  Huttoniana 
  and 
  P. 
  Lindleyana) 
  in 
  the 
  Upper 
  

   Lias. 
  No 
  species 
  is 
  known 
  in 
  the 
  Middle 
  Lias 
  ; 
  here 
  and 
  there 
  frag- 
  

   ments 
  of 
  wood 
  occur, 
  but 
  no 
  determinable 
  form 
  has 
  yet 
  been 
  

   detected. 
  The 
  Plantae 
  of 
  the 
  whole 
  series 
  of 
  the 
  British 
  Jurassic 
  

   rocks 
  number 
  G3 
  genera 
  and 
  191 
  species, 
  130 
  of 
  which 
  belong 
  to 
  

   the 
  Inferior 
  Oolite, 
  mostly 
  from 
  the 
  Yorkshire 
  beds. 
  Pew 
  or 
  none 
  

   occur 
  in 
  the 
  continuous 
  strike 
  of 
  the 
  Lower 
  Oolitic 
  series, 
  from 
  Whitby 
  

   through 
  the 
  mid-eastern 
  part 
  of 
  England 
  and 
  on 
  to 
  Lyme 
  Begis 
  and 
  

   Portland. 
  True 
  it 
  is 
  that 
  the 
  estuarine 
  and 
  terrestrial 
  beds 
  so 
  finely 
  

   shown 
  along 
  the 
  Yorkshire 
  coast 
  are 
  only 
  to 
  be 
  examined 
  in 
  detached 
  

   portions 
  in 
  Lincolnshire, 
  Northamptonshire, 
  &c. 
  The 
  above 
  general 
  

   considerations 
  lead 
  me 
  to 
  discuss 
  the 
  fauna 
  and 
  flora 
  of 
  the 
  Lower, 
  

   Middle, 
  and 
  Upper 
  Lias, 
  or 
  the 
  Lias 
  as 
  a 
  whole 
  as 
  compared 
  with 
  

   the 
  succeeding 
  Middle 
  and 
  Upper 
  Jurassic 
  series. 
  

  

  Plantje 
  : 
  Lower 
  Lias. 
  — 
  The 
  Coniferae 
  and 
  Cycadeaa 
  predominate 
  

   in 
  the 
  Lower 
  Lias 
  ; 
  9 
  of 
  the 
  12 
  genera 
  and 
  11 
  of 
  the 
  species 
  that 
  

   occur 
  belong 
  to 
  these 
  two 
  families. 
  Splicvrococcites 
  maybe 
  an 
  alga. 
  

   Naidites 
  is 
  represented 
  by 
  3 
  species 
  ; 
  Equisetites 
  by 
  1 
  (E. 
  Brocliei) 
  ; 
  

   Otozamites 
  by 
  1 
  species, 
  but 
  this 
  genus 
  greatly 
  predominates 
  in 
  the 
  

   Inferior 
  Oolite. 
  The 
  two 
  Coniferae 
  in 
  the 
  Upper 
  Lias 
  are 
  Pence 
  Hut- 
  

   toniana 
  and 
  P. 
  Lindleyana', 
  no 
  species 
  of 
  this 
  genus 
  passes 
  to 
  any 
  

   higher 
  horizon. 
  I 
  am 
  not 
  aware 
  of 
  any 
  species 
  out 
  of 
  the 
  known 
  

   192 
  occurring 
  in 
  the 
  Jurassic 
  rocks 
  that 
  range 
  from 
  a 
  lower 
  to 
  a 
  

   higher 
  horizon, 
  or 
  pass 
  to 
  any 
  higher 
  beds 
  throughout 
  the 
  whole 
  

   of 
  the 
  Jurassic 
  series. 
  

  

  Middle 
  Lias. 
  — 
  No 
  described 
  or 
  recognized 
  species 
  of 
  plant 
  is 
  known 
  

   to 
  occur 
  in 
  the 
  Middle 
  Lias. 
  Both 
  in 
  Yorkshire 
  and 
  in 
  Dorsetshire, 
  

  

  