﻿Xlvi 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  ing 
  to 
  Minister's 
  tables, 
  12 
  species 
  of 
  the 
  genera 
  CyatJiophyUum, 
  Cala- 
  

   mopora, 
  Terebratula, 
  Avicida, 
  Capidns,Natica'eLiid 
  Naticella 
  are 
  found 
  

   both 
  in 
  the 
  Carboniferous 
  rocks 
  and 
  in 
  the 
  Zechstein. 
  If 
  we 
  add 
  

   the 
  palaeozoic 
  and 
  mixed 
  genera 
  together, 
  and 
  also 
  the 
  species 
  of 
  those 
  

   genera, 
  we 
  get, 
  according 
  to 
  Bronn, 
  26 
  genera 
  in 
  all, 
  out 
  of 
  104, 
  or 
  

   ith, 
  and 
  224 
  species 
  in 
  all, 
  out 
  of 
  774 
  — 
  less 
  than 
  ^rd 
  (-^ths). 
  Mini- 
  

   ster's 
  lists, 
  analyzed 
  in 
  the 
  same 
  way, 
  give 
  

  

  21 
  genera 
  out 
  of 
  79, 
  or 
  nearly 
  |th 
  ; 
  

   133 
  species 
  out 
  of 
  427, 
  or 
  less 
  than 
  -|rd. 
  

  

  In 
  this 
  respect, 
  therefore, 
  they 
  closely 
  agree 
  ; 
  and, 
  judged 
  by 
  a 
  test 
  

   of 
  this 
  kind 
  (which, 
  though 
  very 
  imperfect, 
  is 
  surely 
  significant), 
  the 
  

   St. 
  Cassian 
  beds 
  may 
  be 
  said 
  in 
  rough 
  terms, 
  by 
  their 
  catalogued 
  

   lists 
  of 
  fossils, 
  to 
  be 
  ^rd 
  palaeozoic 
  and 
  |rds 
  mesozoic, 
  although 
  in 
  

   the 
  rocks 
  themselves 
  the 
  palaeozoic 
  genera 
  appear 
  to 
  be 
  comparatively 
  

   more 
  rare 
  than 
  the 
  others. 
  They 
  may, 
  therefore, 
  most 
  conveniently 
  

   be 
  classed 
  with 
  the 
  secondary 
  rocks 
  ; 
  but 
  the 
  wonder 
  is 
  that, 
  placed 
  

   as 
  they 
  are 
  said 
  to 
  be 
  above 
  the 
  Muschelkalk, 
  the 
  St. 
  Cassian 
  beds 
  

   should 
  be 
  so 
  far 
  palaeozoic 
  in 
  the 
  character 
  of 
  their 
  fossils, 
  while 
  the 
  

   underlying 
  Muschelkalk 
  is 
  so 
  essentially 
  secondary. 
  Lying, 
  as 
  they 
  

   do, 
  in 
  a 
  mountain-region 
  which 
  has 
  undergone 
  the 
  extremes 
  of 
  con- 
  

   torted 
  disturbance 
  and 
  denudation, 
  were 
  it 
  not 
  that 
  the 
  order 
  of 
  

   superposition 
  has 
  been 
  so 
  strongly 
  asserted 
  by 
  men 
  of 
  mark, 
  one 
  

   would 
  be 
  tempted 
  to 
  suppose 
  that 
  inversion 
  and 
  confusion 
  of 
  the 
  strata 
  

   has 
  something 
  to 
  do 
  with 
  the 
  presumed 
  order 
  of 
  superposition, 
  and 
  

   that 
  the 
  St. 
  Cassian 
  beds 
  are 
  a 
  stage 
  in 
  time 
  nearer 
  to 
  the 
  Zechstein 
  

   than 
  to 
  the 
  Muschelkalk. 
  In 
  Bronn's 
  catalogue, 
  indeed, 
  they 
  are 
  

   boldly 
  placed 
  in 
  that 
  position. 
  

  

  New 
  Red 
  Marl 
  or 
  Keuper 
  beds. 
  — 
  But 
  in 
  whatever 
  position 
  the 
  

   St. 
  Cassian 
  beds 
  may 
  lie 
  in 
  the 
  geological 
  scale, 
  in 
  our 
  own 
  country 
  

   it 
  is 
  most 
  unlikely 
  that 
  we 
  have 
  any 
  stratigraphical 
  equivalents 
  to 
  

   these 
  beds 
  ; 
  for 
  it 
  is 
  probable 
  that 
  they 
  all 
  belong 
  to 
  a 
  period 
  totally 
  

   unrepresented 
  in 
  England, 
  which 
  came 
  between 
  the 
  close 
  of 
  our 
  

   Bunter 
  sandstone 
  and 
  the 
  beginning 
  of 
  the 
  Keuper 
  marls. 
  

  

  We 
  are 
  helped 
  in 
  coming 
  to 
  this 
  conclusion 
  by 
  the 
  circumstance 
  

   that 
  the 
  white 
  and 
  brown 
  sandstones 
  (water- 
  stones) 
  that 
  lie 
  at 
  the 
  

   base 
  of 
  the 
  New 
  Bed 
  marl 
  lie 
  unconformably 
  on 
  the 
  uppermost 
  

   member 
  of 
  the 
  New 
  Bed 
  sandstone, 
  as 
  shown 
  by 
  Mr. 
  Hull 
  in 
  a 
  cut- 
  

   ting 
  of 
  the 
  St. 
  Helen's 
  railway 
  near 
  Ormskirk 
  ; 
  and 
  in 
  many 
  places 
  

   they 
  overlap 
  the 
  Bunter 
  strata 
  altogether 
  and 
  lie 
  directly 
  on 
  various 
  

   members 
  of 
  the 
  palaeozoic 
  rocks. 
  We 
  have 
  thus 
  clear 
  evidence 
  of 
  a 
  

   stratigraphical 
  break 
  in 
  the 
  Trias 
  of 
  England; 
  and 
  the 
  prodigious 
  

   lapse 
  of 
  time 
  between 
  the 
  close 
  of 
  the 
  Bunter 
  and 
  the 
  beginning 
  of 
  

   the 
  Keuper 
  periods 
  may 
  be 
  inferred 
  from 
  the 
  two 
  vast 
  developments 
  

   of 
  marine 
  life 
  during 
  the 
  St. 
  Cassian 
  and 
  Muschelkalk 
  periods 
  of 
  the 
  

   Continent, 
  between 
  which, 
  according 
  to 
  Miinster, 
  there 
  are 
  only 
  10 
  

   species 
  in 
  common. 
  This 
  idea 
  of 
  the 
  great 
  lapse 
  of 
  time 
  between 
  the 
  

   close 
  of 
  the 
  Bunter 
  epoch 
  and 
  the 
  commencement 
  of 
  the 
  Keuper 
  for- 
  

   mations 
  is 
  strengthened 
  by 
  the 
  circumstance 
  that 
  the 
  rock-salt 
  of 
  our 
  

   Trias 
  lies 
  at 
  the 
  base 
  of 
  the 
  marly 
  series 
  ; 
  and 
  as 
  I 
  know 
  of 
  no 
  other 
  

  

  