﻿474 
  PKOF. 
  J. 
  W. 
  JUDB 
  ON 
  THE 
  EOCENE 
  AND 
  OLIGOCENE 
  

  

  without 
  success, 
  leads 
  me 
  to 
  entertain 
  the 
  view 
  that 
  the 
  former 
  

   supposition 
  is 
  the 
  correct 
  one 
  *. 
  

  

  Above 
  the 
  " 
  marine 
  bed 
  " 
  at 
  Hordwell 
  there 
  are 
  seen 
  about 
  20 
  

   feet 
  of 
  sands 
  and 
  marls 
  with 
  freshwater 
  fossils. 
  But, 
  as 
  Mr. 
  Searles 
  

   Wood 
  pointed 
  out 
  long 
  ago, 
  the 
  forms 
  of 
  Mollusca 
  and 
  Vertebrates 
  

   occurring 
  in 
  these 
  upper 
  freshwater 
  beds 
  are 
  precisely 
  the 
  same 
  as 
  

   those 
  found 
  in 
  the 
  beds 
  underlying 
  the 
  " 
  marine 
  bed." 
  

  

  When 
  these 
  marine 
  beds 
  were 
  first 
  discovered, 
  the 
  whole 
  of 
  the 
  

   fluvio- 
  marine 
  beds 
  of 
  the 
  Hampshire 
  basin 
  were 
  grouped 
  according 
  

   to 
  Webster's 
  classification 
  into 
  the 
  Middle 
  Freshwater, 
  the 
  Upper 
  

   Marine, 
  and 
  the 
  Upper 
  Freshwater. 
  The 
  thin 
  marine 
  band 
  of 
  

   Hordwell 
  was 
  therefore 
  at 
  once 
  claimed 
  as 
  the 
  representative 
  of 
  the 
  

   Middle 
  Marine 
  formation. 
  The 
  proofs 
  brought 
  forward 
  by 
  Prestwich 
  

   and 
  Forbes 
  of 
  the 
  existence 
  of 
  a 
  number 
  of 
  marine 
  or 
  brackish-water 
  

   beds 
  of 
  different 
  ages 
  in 
  the 
  fluvio-marine 
  series, 
  while 
  they 
  have 
  

   caused 
  this 
  classification 
  to 
  be 
  abandoned 
  in 
  many 
  points, 
  do 
  not 
  seem 
  

   to 
  have 
  altogether 
  dispelled 
  the 
  old 
  notions 
  on 
  the 
  subject 
  ; 
  for 
  we 
  

   find 
  the 
  llev. 
  0. 
  Fisher 
  still 
  claiming 
  this 
  thin 
  and 
  inconstant 
  band 
  

   of 
  Hordwell 
  Cliff, 
  which 
  abounds 
  with 
  dwarfed 
  marine 
  shells 
  min- 
  

   gled 
  with 
  freshwater 
  forms, 
  as 
  the 
  undoubted 
  representative 
  of 
  the 
  

   Middle 
  or 
  Marine 
  Headon, 
  the 
  " 
  F«w«s-bed 
  " 
  of 
  collectors; 
  and 
  he 
  

   even 
  identifies 
  the 
  thin 
  limestone 
  band 
  below 
  it 
  with 
  the 
  How- 
  

   Ledge 
  limestone 
  of 
  the 
  Isle 
  of 
  Wight 
  f. 
  

  

  But, 
  as 
  long 
  ago 
  pointed 
  out 
  by 
  Mr. 
  G. 
  B. 
  Sowerby, 
  and 
  admitted 
  

   by 
  Sedgwick 
  and 
  other 
  observers, 
  the 
  division 
  of 
  the 
  Headon 
  beds 
  into 
  

   three 
  series, 
  the 
  upper 
  and 
  lower 
  of 
  which 
  are 
  of 
  freshwater, 
  and 
  the 
  

   middle 
  of 
  marine 
  origin, 
  is 
  one 
  that 
  will 
  not 
  bear 
  the 
  test 
  of 
  exact 
  

   examination. 
  All 
  through 
  the 
  Headon 
  series, 
  bands 
  containing 
  some 
  

   forms 
  of 
  marine 
  mollusca, 
  usually 
  much 
  dwarfed, 
  occur 
  ; 
  such 
  brack- 
  

   ish-water 
  beds 
  exist 
  alike 
  in 
  the 
  so-called 
  Upper, 
  Middle, 
  and 
  Lower 
  

   Headon 
  ; 
  and 
  the 
  utmost 
  that 
  can 
  be 
  said 
  of 
  these 
  brackish-water 
  

   beds, 
  in 
  which 
  both 
  marine 
  and 
  freshwater 
  genera 
  are 
  mingled, 
  is 
  

   that 
  they 
  are 
  perhaps 
  most 
  abundant 
  in 
  the 
  central 
  parts 
  of 
  the 
  

   series. 
  The 
  so-called 
  "marine 
  band" 
  of 
  Hordwell 
  is 
  only 
  one 
  of 
  

   the 
  brackish-water 
  intercalations 
  of 
  the 
  Headon 
  series. 
  

  

  The 
  whole 
  series 
  of 
  strata 
  at 
  Hordwell 
  cliff 
  is 
  therefore 
  as 
  

   follows 
  : 
  — 
  

  

  feet. 
  

  

  ( 
  1 
  ) 
  Sands 
  and 
  marls 
  with 
  freshwater 
  shells 
  12-20 
  seen. 
  

  

  (2) 
  Sand 
  with 
  brackish-water 
  shells 
  ("Marine 
  band") 
  1 
  or 
  less. 
  

  

  (3 
  ) 
  Grey 
  and 
  green 
  shelly 
  marls 
  and 
  sand 
  20 
  

  

  (4) 
  Limngean 
  limestone 
  i 
  

  

  (5) 
  Green 
  marls 
  4 
  

  

  * 
  If 
  the 
  measures 
  of 
  the 
  Marchioness 
  of 
  Hastings 
  and 
  Mr. 
  Wise 
  could 
  be 
  

   trusted, 
  we 
  must 
  admit 
  the 
  existence 
  of 
  two 
  marine 
  bands 
  in 
  the 
  Hordwell 
  

   Cliff; 
  for 
  whereas 
  these 
  authors 
  place 
  their 
  marine 
  band 
  43 
  feet 
  above 
  the 
  

   limestone 
  bed, 
  Dr. 
  Wright 
  reckons 
  only 
  16 
  feet 
  of 
  strata 
  between 
  those 
  two 
  

   beds. 
  My 
  own 
  measurements 
  and 
  those 
  of 
  the 
  Rev. 
  O. 
  Fisher 
  support 
  the 
  views 
  

   of 
  Dr. 
  Wright 
  as 
  to 
  the 
  true 
  place 
  of 
  the 
  marine 
  bed 
  ; 
  Prof. 
  Ed. 
  Forbes 
  (Quart. 
  

   Journ. 
  Geol. 
  Soc. 
  vol. 
  ix. 
  1853, 
  p. 
  268), 
  however, 
  thought 
  the 
  Marchioness 
  of 
  

   Hastings's 
  section 
  more 
  reliable 
  than 
  that 
  of 
  Dr. 
  Wright. 
  

  

  t 
  Geol. 
  Mag. 
  new 
  ser. 
  dec. 
  ii. 
  vol. 
  ix. 
  (1882) 
  p. 
  139. 
  

  

  