﻿PLIOCENE 
  PERIOD 
  IN 
  ENGLAND. 
  701 
  

  

  I 
  am 
  not 
  aware 
  of 
  any 
  evidence 
  to 
  prove 
  that 
  in 
  the 
  vales 
  of 
  York 
  

   and 
  Tees 
  this 
  gravel 
  originated 
  in 
  a 
  redeprcssion 
  ; 
  but, 
  on 
  the 
  other 
  

   hand, 
  I 
  know 
  of 
  nothing 
  to 
  suggest 
  that 
  the 
  redepression, 
  of 
  which 
  

   in 
  connexion 
  with 
  this 
  formation 
  we 
  get 
  such 
  clear 
  evidence 
  from 
  the 
  

   Thames 
  to 
  the 
  Humber, 
  did 
  not 
  extend 
  to 
  these 
  parts 
  of 
  England 
  also. 
  

  

  The 
  Upper 
  Clay 
  of 
  Cheshire, 
  Lancashire, 
  and 
  Cumberland, 
  which 
  

   in 
  Stage 
  VII. 
  I 
  refer 
  to 
  the 
  minor 
  glaciation, 
  and 
  connect 
  with 
  that 
  

   thus 
  overlying 
  the 
  Gyrena-f 
  orm'dtion 
  in 
  Yorkshire, 
  is 
  in 
  most 
  parts 
  

   of 
  the 
  lower 
  ground 
  of 
  the 
  north-west 
  of 
  England 
  separated 
  from 
  

   the 
  clay 
  of 
  the 
  major 
  glaciation 
  by 
  sand 
  and 
  gravel, 
  corresponding 
  

   to 
  that 
  of 
  the 
  Gyren 
  ^-formation 
  of 
  the 
  eastern 
  side 
  of 
  England 
  ; 
  and 
  

   this 
  contains 
  marine 
  mollusca. 
  Inasmuch, 
  however, 
  as 
  the 
  sand 
  

   and 
  gravel 
  which 
  (corresponding 
  to 
  that 
  of 
  the 
  east 
  shown 
  under 
  

   the 
  letters 
  e 
  and/') 
  was 
  deposited 
  after 
  the 
  retreat 
  and 
  disappear- 
  

   ance 
  of 
  the 
  ice 
  of 
  the 
  major 
  glaciation 
  in 
  the 
  north-west 
  contains 
  

   molluscan 
  remains, 
  there 
  appear 
  to 
  be 
  no 
  means 
  of 
  distinguishing 
  the 
  

   one 
  from 
  the 
  other; 
  and 
  indeed, 
  whether 
  the 
  redrepression 
  extended 
  

   to 
  that 
  part 
  of 
  England 
  or 
  not, 
  the 
  sea 
  from 
  the 
  original 
  great 
  in- 
  

   crement 
  of 
  depression 
  in 
  that 
  direction 
  probably 
  continued 
  to 
  cover 
  

   the 
  lower 
  elevations 
  there 
  ; 
  so 
  that 
  the 
  redepression, 
  if 
  it 
  extended 
  

   to 
  that 
  part, 
  would, 
  owing 
  to 
  the 
  abrupt 
  way 
  in 
  which 
  the 
  plain 
  of 
  

   Cheshire 
  and 
  south-west 
  Lancashire 
  is 
  bounded 
  by 
  the 
  mountain- 
  

   region, 
  but 
  very 
  little 
  enlarge 
  the 
  area 
  thus 
  remaining 
  sea-covered. 
  

   I 
  have 
  not 
  therefore 
  attempted 
  to 
  delineate 
  by 
  a 
  line 
  on 
  Map 
  5 
  

   the 
  limit 
  of 
  the 
  submergence 
  of 
  the 
  north-west 
  of 
  England 
  during 
  

   the 
  CV/r^irt-formation, 
  as 
  I 
  have 
  done 
  that 
  of 
  the 
  north-east 
  : 
  but 
  

   the 
  area 
  which 
  is 
  shaded 
  with 
  very 
  fine 
  dots 
  in 
  that 
  map 
  to 
  indicate 
  

   the 
  moraine 
  of 
  the 
  minor 
  glaciation 
  there 
  can 
  differ, 
  I 
  think, 
  but 
  

   little 
  from 
  this 
  limit 
  also. 
  

  

  As 
  the 
  clay 
  of 
  the 
  minor 
  glaciation, 
  or 
  Upper 
  Clay, 
  in 
  the 
  north- 
  

   west 
  (G' 
  of 
  fig. 
  LIII.), 
  contains 
  marine 
  shells 
  which 
  seem 
  to 
  have 
  

   been 
  introduced 
  in 
  a 
  similar 
  way 
  to 
  those 
  found 
  in 
  the 
  clay 
  of 
  

   the 
  major 
  glaciation 
  of 
  that 
  part 
  of 
  England 
  (viz., 
  by 
  being 
  dropped 
  

   over 
  the 
  place 
  where 
  the 
  moraine 
  was 
  undergoing 
  extrusion 
  beneath 
  

   the 
  sea 
  by 
  floe-ice 
  bringing 
  them 
  from 
  shore-lines), 
  and 
  as 
  the 
  

   corresponding 
  clay 
  of 
  the 
  north-east 
  seems 
  to 
  be 
  free 
  from 
  shells, 
  

   and 
  in 
  other 
  ways 
  indicates 
  that 
  emergence 
  from 
  the 
  depression 
  

   I 
  have 
  just 
  traced 
  took 
  place 
  before 
  it 
  was 
  laid 
  upon 
  the 
  Cyrena- 
  

   formation, 
  the 
  middle 
  sand 
  must 
  reach 
  to 
  elevations 
  as 
  great 
  as, 
  

   and 
  probably 
  greater 
  than, 
  those 
  to 
  which 
  the 
  part 
  of 
  this 
  Upper 
  

   Clay 
  of 
  the 
  north-west 
  which 
  contains 
  shells 
  reaches. 
  My 
  im- 
  

   pression 
  has 
  been 
  that 
  in 
  the 
  shell-bearing 
  condition 
  this 
  clay 
  was 
  

   confined 
  to 
  low 
  levels, 
  such 
  as 
  that 
  of 
  Blackpool 
  Cliff, 
  Mersey 
  

   Docks, 
  &c: 
  but 
  Mr. 
  Shone 
  speaks 
  of 
  it 
  as 
  in 
  this 
  condition 
  reach- 
  

   ing 
  the 
  elevation 
  of 
  000 
  feet 
  at 
  Macclesfield 
  * 
  and 
  Arnfield. 
  

  

  If 
  such 
  really 
  be 
  the 
  case, 
  this 
  would 
  conflict 
  considerably 
  with 
  

  

  * 
  Mr. 
  ftarbishire, 
  in 
  vol. 
  ii. 
  p. 
  41 
  of 
  theGeol. 
  Mag., 
  calls 
  the 
  clay 
  at 
  Maccles- 
  

   field 
  " 
  Lower 
  Boulder 
  Clay 
  ; 
  " 
  and 
  as 
  the 
  bed 
  on 
  which 
  the 
  gravel 
  at 
  the 
  ceme- 
  

   tery 
  which 
  yielded 
  him 
  the 
  shells 
  he 
  there 
  describes 
  from 
  thence 
  rests, 
  he 
  says, 
  

   at 
  600 
  feet 
  elevation, 
  on 
  clay, 
  I 
  presume 
  that 
  this 
  must 
  be 
  the 
  Lower 
  instead 
  of 
  

   the 
  Upper 
  Clay. 
  

  

  