﻿86 
  PROCEEDINGS 
  OP 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  Howardian 
  chain 
  a 
  very 
  different 
  development 
  is 
  observed. 
  He 
  

   submits 
  a 
  section 
  of 
  the 
  latter 
  in 
  the 
  valley 
  of 
  the 
  Derwent, 
  south- 
  

   west 
  of 
  Malton, 
  as 
  an 
  example 
  or 
  type 
  of 
  the 
  whole 
  : 
  this 
  is 
  elabo- 
  

   rately 
  discussed, 
  and 
  forms 
  an 
  important 
  part 
  of 
  Mr. 
  Hudleston's 
  

   researches 
  upon 
  the 
  Lower 
  Oolites. 
  

  

  Continuous 
  with 
  part 
  1, 
  but 
  in 
  the 
  following 
  year, 
  1875, 
  the 
  

   higher 
  members 
  or 
  subdivisions 
  of 
  the 
  Yorkshire 
  Oolites 
  are 
  critically 
  

   worked 
  out 
  : 
  they 
  consist 
  of 
  six 
  subdivisions, 
  two 
  of 
  which 
  are 
  

   partly 
  new 
  ; 
  these 
  are 
  the 
  " 
  shales 
  with 
  Avicula 
  echinata" 
  and 
  the 
  

   uppermost 
  or 
  " 
  supracoralline 
  rocks." 
  All 
  are 
  seen 
  along 
  the 
  coast. 
  

   These 
  six 
  subdivisions 
  are 
  : 
  — 
  

  

  1. 
  The 
  Shales 
  with 
  Avicula 
  echinata. 
  

  

  2. 
  The 
  Kellaways 
  Rock. 
  

  

  3. 
  The 
  Oxford 
  Clay. 
  

  

  4. 
  The 
  Lower 
  Calcareous 
  Grit. 
  

  

  5. 
  The 
  Coralline 
  Oolite. 
  

  

  6. 
  The 
  Supra-Coralline 
  beds. 
  

  

  The 
  Shales 
  with 
  Avicula 
  echinata, 
  not 
  very 
  distinct 
  from 
  the 
  

   Cornbrash, 
  Mr. 
  Hudleston 
  regards 
  as 
  anticipating 
  in 
  a 
  measure 
  

   the 
  physical 
  conditions 
  of 
  the 
  Oxford 
  Clay, 
  but 
  interrupted 
  for 
  a 
  

   time 
  by 
  the 
  intervention 
  of 
  the 
  great 
  arenaceous 
  deposit 
  of 
  the 
  

   Kellaways 
  series. 
  At 
  Scarborough 
  they 
  are 
  from 
  12 
  to 
  15 
  feet 
  thick, 
  

   in 
  Newton 
  Dale 
  10 
  feet. 
  They 
  may 
  be 
  the 
  Hambleton 
  argillaceous 
  

   beds 
  of 
  Phillips 
  at 
  the 
  base 
  of 
  the 
  Kellaways 
  ; 
  possibly, 
  also, 
  as 
  sug- 
  

   gested 
  by 
  Hudleston, 
  the 
  " 
  Avicula- 
  echinata 
  beds" 
  of 
  Porta 
  West- 
  

   phalica, 
  in 
  Germany, 
  may 
  be 
  of 
  the 
  same 
  age 
  and 
  position, 
  although 
  

   it 
  is 
  here 
  von 
  Seebach 
  draws 
  the 
  line 
  between 
  the 
  Middle 
  and 
  Upper 
  

   Jura. 
  Dr. 
  Brauns 
  extends 
  that 
  line 
  to 
  the 
  top 
  of 
  the 
  " 
  Ornatus 
  

   clays," 
  which 
  have 
  their 
  equivalents 
  in 
  the 
  highest 
  part 
  of 
  the 
  

   Kellaways 
  Kock 
  of 
  Scarborough. 
  

  

  Fourteen 
  species 
  of 
  fossils 
  are 
  recorded 
  from 
  these 
  shales 
  — 
  4 
  genera 
  

   of 
  Monomyaria 
  with 
  7 
  species, 
  4 
  genera 
  of 
  Dimyaria 
  with 
  4 
  species, 
  

   Waldheimia 
  lagenalis,Bhynchonella 
  Leedsii, 
  and 
  Glyphea 
  StricJclandi. 
  

   All 
  of 
  these 
  except 
  the 
  two 
  last-named 
  species 
  have 
  a 
  wide 
  Jurassic 
  

   range. 
  

  

  No 
  description 
  of 
  the 
  Kellaways 
  Rock 
  ever 
  given 
  approaches 
  

   the 
  physical 
  history 
  and 
  palseontological 
  analysis 
  given 
  by 
  Mr. 
  

   Hudleston. 
  The 
  sections 
  are 
  detailed 
  bed 
  by 
  bed; 
  and 
  I 
  am 
  happy 
  

   to 
  be 
  able 
  to 
  follow 
  him 
  in 
  detail, 
  from 
  personal 
  examination, 
  

   though 
  not 
  with 
  a 
  knowledge 
  equal 
  to 
  his 
  own. 
  The 
  great 
  mass 
  of 
  

   the 
  fossils 
  occur 
  in 
  the 
  upper 
  ferruginous 
  hard 
  rock 
  and 
  the 
  upper 
  

   tier 
  of 
  solid 
  stone, 
  in 
  which 
  Belemnites 
  Owenii 
  and 
  Gryphosa 
  dilatata 
  

   occur 
  abundantly, 
  with 
  the 
  Ornatus 
  Ammonites 
  A. 
  Gowerianus, 
  A. 
  

   Duncani, 
  A. 
  Jason, 
  A. 
  Gulielmi, 
  A. 
  gemmatus, 
  &c. 
  &e. 
  The 
  group 
  

   Cordati, 
  A. 
  Lamberti, 
  A. 
  cordatus, 
  A. 
  fleocicostatus, 
  &c, 
  indeed 
  most 
  

   of 
  the 
  fossils, 
  especially 
  the 
  Ammonites, 
  are 
  from 
  the 
  subcrystalline 
  

   rock, 
  or 
  " 
  upper 
  tier." 
  The 
  conditions 
  of 
  this 
  rock 
  are 
  traced 
  along 
  

   the 
  coast 
  from 
  the 
  Castle 
  Hill, 
  Scarborough, 
  to 
  Newbiggin 
  Wyke 
  

   at 
  Gristhorpe 
  Cliff, 
  where 
  it 
  thins 
  out 
  and 
  is 
  lost, 
  having, 
  in 
  5| 
  

  

  