﻿STRATA 
  OE 
  THE 
  HAMPSHIRE 
  BASIN. 
  467 
  

  

  series 
  *. 
  Mr. 
  Fisher's 
  reason 
  for 
  proposing 
  this 
  great 
  change 
  in 
  the 
  

   classification 
  of 
  the 
  Whitecliff-Bay 
  beds 
  was 
  that 
  he 
  considered 
  certain 
  

   f 
  ossiliferous 
  bands 
  conld 
  he 
  traced 
  continuously 
  wherever 
  the 
  Brackle- 
  

   sham 
  series 
  is 
  exposed 
  over 
  the 
  whole 
  Hampshire 
  basin. 
  In 
  each 
  

   of 
  these 
  fossil-beds, 
  which 
  vary 
  in 
  thickness 
  from 
  6 
  inches 
  to 
  6 
  feet, 
  

   he 
  assures 
  us 
  that 
  a 
  similar 
  matrix 
  and 
  the 
  same 
  assemblage 
  of 
  

   fossils 
  can 
  be 
  recognized, 
  and 
  he 
  assumes 
  the 
  continuity 
  of 
  these 
  

   fossiliferous 
  bands 
  over 
  the 
  whole 
  of 
  the 
  wide 
  area 
  through 
  which 
  

   the 
  Brackleshani 
  series 
  can 
  be 
  followed 
  — 
  an 
  area 
  measuring 
  40 
  

   miles 
  from 
  east 
  to 
  west, 
  and 
  20 
  miles 
  from 
  north 
  to 
  south. 
  

  

  But 
  it 
  is 
  only 
  fair 
  to 
  remember 
  that 
  the 
  occurrence 
  of 
  these 
  fossil- 
  

   beds 
  is 
  capable 
  of 
  a 
  different 
  explanation. 
  Among 
  the 
  inconstant 
  

   strata 
  deposited 
  (as 
  the 
  Brackleshams 
  undoubtedly 
  were) 
  near 
  

   the 
  estuary 
  of 
  a 
  great 
  river, 
  similar 
  materials 
  with 
  the 
  same 
  

   assemblage 
  of 
  fossils 
  would 
  be 
  deposited 
  wherever 
  the 
  same 
  physical 
  

   conditions 
  prevailed 
  ; 
  and 
  it 
  is 
  not 
  necessary 
  to 
  assume 
  that 
  similar 
  

   fossil-beds 
  exposed 
  at 
  widely 
  separated 
  localities 
  are 
  necessarily 
  

   parts 
  of 
  one 
  continuous 
  stratum. 
  Mr. 
  Fisher's 
  argument 
  in 
  favour 
  

   of 
  including 
  so 
  great 
  a 
  thickness 
  of 
  the 
  Whiteclifi-Bay 
  beds 
  in 
  the 
  

   Bracklesham 
  series 
  rests 
  to 
  a 
  great 
  extent 
  also 
  on 
  his 
  reference 
  of 
  

   the 
  fossiliferous 
  strata 
  of 
  Hunting 
  Bridge 
  to 
  that 
  geological 
  horizon 
  ; 
  

   and 
  this 
  is 
  a 
  conclusion 
  which 
  is 
  far 
  from 
  being 
  free 
  from 
  doubt. 
  

   Although 
  it 
  is 
  difficult 
  among 
  the 
  poorly 
  fossiliferous 
  beds 
  of 
  White- 
  

   cliff 
  Bay 
  to 
  fix 
  the 
  exact 
  line 
  of 
  demarcation 
  between 
  the 
  Brackles- 
  

   ham 
  and 
  Barton 
  series, 
  yet 
  there 
  are 
  good 
  grounds 
  for 
  believing 
  

   that 
  the 
  Barton 
  Clays 
  have 
  a 
  greater 
  thickness 
  and 
  importance 
  at 
  

   that 
  locality 
  than 
  is 
  ascribed 
  to 
  them 
  by 
  Mr. 
  Fisher. 
  

  

  With 
  respect 
  to 
  the 
  correlation 
  of 
  the 
  richly 
  fossiliferous 
  strata 
  of 
  

   the 
  Hampshire 
  and 
  Paris 
  basins, 
  Mr. 
  Prestwich's 
  admirable 
  papers 
  

   left 
  little 
  to 
  be 
  accomplished, 
  and 
  the 
  discovery 
  of 
  fresh 
  species 
  in 
  

   the 
  two 
  areas 
  has 
  completely 
  confirmed 
  the 
  conclusions 
  arrived 
  at 
  

   by 
  that 
  author 
  with 
  the 
  assistance 
  of 
  Prof. 
  Morris 
  and 
  the 
  late 
  

   Mr. 
  F. 
  Edwards. 
  As 
  early 
  as 
  1847 
  1 
  it 
  was 
  proved 
  that 
  the 
  

   Bracklesham 
  beds 
  contain 
  the 
  same 
  fauna 
  as 
  the 
  Calcaire 
  grossier 
  ; 
  

   and 
  in 
  1857 
  the 
  exact 
  correspondence 
  of 
  the 
  Bracklesham 
  series 
  and 
  

   the 
  Barton 
  series 
  with 
  the 
  Middle 
  and 
  Upper 
  Eocene 
  of 
  France 
  and 
  

   Belgium 
  was 
  established 
  beyond 
  all 
  chance 
  of 
  controversy 
  £. 
  

  

  But 
  the 
  correlation 
  of 
  the 
  richly 
  fossiliferous 
  Hampshire 
  beds 
  

   with 
  the 
  barren 
  Middle 
  Eocene 
  of 
  the 
  London 
  basin 
  has 
  proved 
  a 
  

   far 
  more 
  difficult 
  task 
  ; 
  and 
  the 
  views 
  generally 
  accepted 
  on 
  this 
  

   question 
  are, 
  to 
  say 
  the 
  least 
  of 
  them, 
  still 
  open 
  to 
  very 
  grave 
  

   doubt. 
  

  

  The 
  Lower 
  Bagshot 
  beds 
  of 
  the 
  London 
  basin 
  have 
  a 
  thickness 
  of 
  

   from 
  100 
  to 
  150 
  feet 
  ; 
  they 
  contain 
  only 
  a 
  few 
  obscure 
  vegetable 
  

   remains, 
  and 
  are 
  in 
  all 
  probability 
  of 
  freshwater 
  origin. 
  The 
  sands 
  

   and 
  pipe-clays 
  which 
  at 
  Studland 
  Bay, 
  Alum 
  Bay, 
  and 
  Whitecliff 
  

   Bay 
  are 
  seen 
  immediately 
  overlying 
  the 
  representatives 
  of 
  the 
  

  

  * 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xviii. 
  (1862) 
  p. 
  05. 
  

   t 
  Ibid. 
  vol. 
  iii. 
  (1847) 
  p. 
  354. 
  

   \ 
  Ibid. 
  vol. 
  xiii. 
  (1857) 
  p. 
  90. 
  

  

  