﻿NEWTON 
  : 
  GEOLOGICAL 
  ZONES 
  AND 
  THEIR 
  MOLLUSCA. 
  291 
  

  

  Bath 
  Gkoup 
  / 
  Zone 
  of 
  Terebratula 
  lagenalis. 
  

   or 
  EathonianI 
  ,, 
  T. 
  digona. 
  

   The 
  Bathoniaii 
  localities 
  embraced 
  Eushden 
  (JS'ortliamptonshire), 
  

   Stanton 
  and 
  Malmsbury 
  (Wilts), 
  Bradford 
  and 
  Hampton 
  Cliff 
  (Wilts). 
  

  

  r 
  Zone 
  of 
  Ammonites 
  Parkinsoni. 
  

   _, 
  ^ 
  ,, 
  A. 
  Jlumphresiamis. 
  

  

  Bateux 
  Giiom'l 
  ^^ 
  A. 
  Scmzei. 
  

  

  "^■^ 
  1 
  ,, 
  A. 
  MurcMsonce. 
  

  

  Bajocian 
  ^^ 
  Trigonia 
  nains. 
  

  

  ,, 
  Ammonites 
  tonilosus. 
  

  

  The 
  Bajocian 
  localities 
  were 
  : 
  Leckhampton 
  Hill 
  (Gloucestershire), 
  

   Duudry 
  (Somersetshire), 
  Scarborough 
  and 
  Blue 
  Wyke 
  (Yorkshire), 
  

   Burton 
  Bradstock 
  (Dorset), 
  Yeovil 
  (Somerset), 
  Frocester 
  (Gloucester- 
  

   shire). 
  European 
  : 
  South-West 
  Germany 
  and 
  France. 
  

  

  Dr. 
  Wright 
  ^ 
  succeeded 
  Oppel 
  in 
  zoning 
  the 
  Inferior 
  Oolite 
  of 
  the 
  

   South 
  of 
  England 
  and 
  the 
  Yorkshire 
  coast, 
  a 
  work 
  carried 
  out 
  very 
  

   much 
  upon 
  the 
  same 
  lines, 
  as 
  he 
  adopted 
  the 
  triple 
  zonal 
  subdivisions 
  

   of 
  that 
  author. 
  Wright's 
  comparisons 
  of 
  these 
  zonal 
  faunas 
  demonstrated 
  

   a 
  similarity 
  of 
  facies 
  in 
  each 
  area, 
  to 
  prove 
  which 
  he 
  furnished 
  lists 
  

   of 
  the 
  fossils 
  from 
  the 
  zones 
  of 
  this 
  series 
  of 
  rocks. 
  He 
  insisted 
  upon 
  

   the 
  importance 
  of 
  specific 
  lists, 
  as 
  it 
  was 
  only 
  by 
  work 
  of 
  this 
  analytical 
  

   character 
  that 
  the 
  conclusions 
  of 
  the 
  geologist 
  and 
  palseontologist 
  could 
  

   possibly 
  agree, 
  satisfactory 
  results 
  being 
  only 
  attainable 
  "by 
  accurate 
  

   observation 
  and 
  a 
  rigorous 
  determination 
  of 
  the 
  specific 
  characters 
  of 
  

   the 
  fossils 
  imbedded 
  in 
  each 
  superimposed 
  stratum". 
  Each 
  zone 
  was 
  

   characterized 
  bj' 
  certain 
  species 
  of 
  Mollusca 
  and 
  other 
  invertebrates, 
  

   which 
  were 
  special 
  to 
  it, 
  and 
  the 
  author 
  further 
  emphasized 
  the 
  fact 
  

   that 
  there 
  was 
  an 
  unequal 
  development 
  of 
  the 
  zones 
  not 
  only 
  in 
  

   England 
  but 
  also 
  in 
  France 
  and 
  Germany. 
  He 
  adopted 
  Oppel's 
  three 
  

   zonal 
  subdivisions 
  for 
  this 
  series 
  of 
  rocks. 
  

  

  (1) 
  Zone 
  of 
  Ammo7iites 
  Parlcinsoni 
  : 
  observed 
  at 
  Leckhampton 
  Hill, 
  

   llavenf=gate 
  Hill, 
  Cold 
  Comfort, 
  Birdlip 
  Hill, 
  Rodborough 
  Hill, 
  Dundry, 
  

   Bath, 
  Yeovil, 
  and 
  near 
  Bridport. 
  

  

  In 
  the 
  various 
  beds 
  of 
  this 
  zone 
  the 
  following 
  Mollusca 
  were 
  

   regarded 
  as 
  characteristic: 
  — 
  

  

  Cephalopoda. 
  — 
  Ammo7iites 
  Parlcinsoni, 
  Martinsi, 
  Triiellei, 
  suhradiatus. 
  

   Gastropoda. 
  — 
  Chemnitzia 
  procera. 
  

  

  Peliccypoda. 
  — 
  ITomomya 
  gihhosa, 
  Ceromya 
  plicata, 
  Trigonia 
  sigvata, 
  

   Gryplicea 
  stiblohata, 
  Pholadomya 
  Ileraulti, 
  Corhicella 
  complanata 
  . 
  

  

  (2) 
  Zone 
  of 
  Ammonites 
  Humphresianus 
  : 
  present 
  at 
  Cleeve 
  Hill, 
  

   Dundry 
  Hill, 
  Gristhorpe 
  Baj^ 
  (Yorkshire), 
  Glastonbury 
  Tor, 
  Yeovil, 
  

   Henbury, 
  Half-way 
  House, 
  Bradford 
  Abbas. 
  

  

  The 
  chief 
  Mollusca 
  distributed 
  through 
  this 
  zone 
  were 
  given 
  as 
  — 
  

   Cephalopoda. 
  — 
  Atmnoniies 
  Humphresianus, 
  Procchi, 
  Blagdeni, 
  

  

  Prailcenridgei, 
  concavus, 
  Dorsetensis, 
  Sotverbyi. 
  

   Gastropoda. 
  — 
  Chemnitzia 
  Samanni 
  ; 
  Pleiirotomaria 
  ornata, 
  fasciata, 
  

  

  punctata; 
  Alar 
  ia 
  Phillip 
  si 
  ; 
  Turbo 
  capitaneus. 
  

  

  ^ 
  Quart. 
  Journ. 
  Geol. 
  See, 
  vol. 
  xvi, 
  p. 
  1, 
  1860. 
  

   VOL. 
  IX. 
  — 
  JUNE, 
  1911. 
  21 
  

  

  