﻿COTTESWOLD, 
  MIDFORD, 
  AND 
  YEOVIL 
  SANDS, 
  ETC. 
  459 
  

  

  beds. 
  To 
  anyone 
  acquainted 
  with 
  the 
  Cotteswolds 
  the 
  idea 
  of 
  

   placing 
  the 
  greater 
  part 
  of 
  the 
  thoroughly 
  oolitic 
  strata 
  there 
  

   exhibited 
  — 
  the 
  Pea-grit, 
  Lower 
  Freestone, 
  Oolite 
  Marl, 
  Upper 
  Free- 
  

   stone, 
  Lower 
  Trigonia-grit, 
  and 
  Gryphite-grit 
  — 
  in 
  the 
  Lias 
  must 
  seem 
  

   very 
  extraordinary; 
  but 
  anyone 
  who 
  visits 
  Dundry 
  in 
  North 
  Somerset, 
  

   Corton 
  Downs 
  in 
  South 
  Somerset, 
  and 
  Sherborne 
  in 
  Dorset, 
  and 
  sees 
  

   the 
  Concavum-beds 
  of 
  those 
  places, 
  with 
  their 
  truly 
  Liassic 
  appearance, 
  

   and 
  remembers 
  at 
  the 
  same 
  time 
  that 
  clayey 
  conditions 
  prevailed 
  on 
  

   the 
  continent 
  until 
  a 
  much 
  later 
  date 
  than 
  with 
  us, 
  will 
  begin 
  to 
  

   understand 
  the 
  motives 
  which 
  sway 
  continental 
  geologists 
  when 
  they 
  

   wish 
  to 
  place 
  these 
  strata 
  in 
  the 
  Lias 
  *. 
  

  

  I 
  was 
  strongly 
  opposed 
  to 
  Dr. 
  Vacek's 
  views 
  at 
  first, 
  especially 
  

   because 
  he 
  had 
  made 
  many 
  errors 
  in 
  describing 
  our 
  English 
  

   strata 
  ; 
  and 
  had 
  then 
  drawn 
  inferences 
  therefrom 
  which 
  I 
  knew 
  

   could 
  not 
  be 
  sustained. 
  

  

  Now, 
  instead 
  of 
  regarding 
  them 
  as 
  Lias, 
  I 
  propose 
  (being 
  especially 
  

   struck 
  with 
  certain 
  palaeontological 
  features 
  of 
  the 
  series) 
  to 
  describe 
  

   all 
  the 
  strata 
  from 
  the 
  Falciferum-zone 
  to 
  the 
  top 
  of 
  the 
  Concavum- 
  

   beds 
  by 
  d'Orbigny 
  's 
  term 
  "Toarcien" 
  ; 
  but 
  I 
  would 
  not 
  place 
  the 
  

   strata 
  so 
  named 
  as 
  subsidiary 
  to 
  either 
  Lias 
  or 
  Oolite. 
  I 
  cannot 
  say 
  

   that 
  this 
  idea 
  is 
  new. 
  Prof 
  Eugene 
  Deslongschamps 
  (op. 
  cit. 
  footnote, 
  

   p. 
  100) 
  says 
  of 
  the 
  same 
  series 
  : 
  " 
  Les 
  marnes 
  infra-oolithiques 
  

   representent 
  exactement 
  l'etage 
  Toarcien 
  de 
  M. 
  d'Orbigny." 
  Now 
  

   he 
  had 
  already 
  proposed 
  the 
  following 
  classification 
  for 
  a 
  portion 
  of 
  

   the 
  Jurassic 
  strata 
  (pages 
  70, 
  71) 
  : 
  — 
  

  

  " 
  Systeme 
  Oolithique 
  inferieur. 
  

   1°. 
  Les 
  marnes 
  infra-oolithiques 
  ; 
  

   2°. 
  L'oolithe 
  inferieure 
  ; 
  

   3°. 
  Le 
  fuller's 
  earth 
  ; 
  

   4°. 
  La 
  grancle 
  oolithe." 
  

  

  The 
  first 
  and 
  lowest 
  of 
  these 
  stages, 
  namely, 
  " 
  Les 
  marnes 
  infra- 
  

   oolithiques" 
  are 
  stated 
  to 
  be 
  composed 
  as 
  follows 
  (pp. 
  73, 
  74) 
  : 
  — 
  

  

  1°. 
  Argiles 
  a 
  poissons. 
  

  

  f 
  1°. 
  Couches 
  a 
  Ammonites 
  bifrons 
  

   et 
  serpentinus 
  ; 
  

   2°. 
  Id. 
  a 
  Ammonites 
  et 
  Lima 
  

  

  toarcensis. 
  

   1°. 
  Couches 
  a 
  Ami 
  

  

  2°. 
  Marnes 
  moyennes. 
  

  

  3°. 
  Calcaires 
  super- 
  i 
  

  

  A 
  r 
  primordiaUs 
  ; 
  

  

  leures 
  a 
  Ammo- 
  \ 
  0o 
  ' 
  , 
  Terehr 
  J 
  v 
  j 
  a 
  

   nites 
  Murchisonce. 
  - 
  • 
  1(1 
  - 
  a 
  J-erebratuUi 
  

  

  \ 
  perovalis. 
  

  

  From 
  this 
  we 
  see 
  that 
  d'Orbigny's 
  " 
  Toarcien 
  " 
  and 
  Prof. 
  Eugene 
  

   Deslongschamps's 
  "Marnes 
  infra-oolithiques" 
  comprise 
  what 
  we 
  now 
  

   know 
  as 
  Upper 
  Lias, 
  together 
  with 
  what 
  Mr. 
  Hudleston 
  calls 
  the 
  

   Lower 
  division 
  of 
  the 
  Inferior 
  Oolite, 
  namely, 
  to 
  the 
  top 
  of 
  the 
  zone 
  

   of 
  Lioceras 
  concavum 
  t. 
  

  

  * 
  D'Orbigny 
  placed 
  these 
  same 
  beds 
  in 
  the 
  Lias 
  — 
  Toarci 
  en 
  = 
  Upper 
  Lias. 
  

   Eugene 
  Deslongschamps 
  was 
  at 
  first 
  of 
  the 
  same 
  opinion 
  (Etudes 
  jurass. 
  inf. 
  

   Normandie, 
  p. 
  99, 
  footnote, 
  1864). 
  

  

  t 
  This 
  horizon 
  was 
  formerly 
  called 
  the 
  " 
  Sowero^/i-zoiae." 
  The 
  reason 
  for 
  

   the 
  present 
  designation 
  may 
  be 
  found 
  in 
  Mr. 
  Hudleston's 
  Monogr. 
  Gast. 
  Inf. 
  

   Oolite, 
  p. 
  44, 
  Pal. 
  Soc. 
  (March 
  1887), 
  and 
  in 
  my 
  Monogr. 
  Inf. 
  Ool. 
  Amm, 
  Pal. 
  

   Soc. 
  p. 
  63, 
  March 
  (1889). 
  

  

  