﻿114 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  cula 
  ovalis, 
  Cidaris 
  Smithii, 
  Echinobrissus 
  scutatus, 
  &c, 
  are 
  amongst 
  

   the 
  forms 
  that 
  abound. 
  The 
  fossils 
  collected 
  from 
  the 
  Upper 
  Calca- 
  

   reous 
  Grit 
  of 
  Pickering 
  number 
  26 
  species, 
  19 
  of 
  which 
  are 
  bivalves. 
  

   Details 
  are 
  given 
  on 
  p. 
  347 
  of 
  the 
  fine 
  section 
  at 
  Sinnington 
  in 
  

   the 
  Upper 
  Limestones 
  of 
  the 
  middle 
  division 
  of 
  Pickering 
  (loc. 
  cit. 
  

   pp. 
  333-340). 
  

  

  The 
  Hambleton 
  District. 
  

   This 
  extensive 
  area 
  is 
  now 
  clearly 
  understood 
  through 
  the 
  re- 
  

   searches 
  of 
  Messrs. 
  Blake 
  and 
  Hudleston. 
  They 
  describe 
  five 
  

   horizons 
  or 
  subformations, 
  tracing 
  them 
  over 
  a 
  distance 
  of 
  eight 
  

   miles, 
  namely 
  : 
  — 
  

  

  1. 
  Lower 
  Calcareous 
  Grit, 
  ^ 
  

  

  2. 
  Hambleton 
  Oolite, 
  

  

  3. 
  Middle 
  Calcareous 
  Grit, 
  ^Corallian. 
  

  

  4. 
  Coralline 
  Oolite, 
  

  

  5. 
  Upper 
  Calcareous 
  Grit, 
  j 
  

   Kimmeridge 
  Clay. 
  

  

  The 
  characteristic 
  fossils 
  are 
  given 
  in 
  the 
  description 
  of 
  the 
  five 
  

   horizons 
  ; 
  neither 
  time 
  or 
  space 
  will 
  allow 
  me 
  to 
  follow 
  the 
  authors 
  

   through 
  their 
  careful 
  analysis 
  of 
  the 
  physical 
  structure 
  of 
  the 
  county 
  

   or 
  their 
  deductions 
  from 
  the 
  organic 
  remains. 
  The 
  fossils 
  from 
  the 
  

   Coral 
  Rag, 
  the 
  Calcareous 
  Grits, 
  and 
  Coralline 
  Oolites 
  are 
  given 
  

   from 
  several 
  quarries 
  and 
  cuttings 
  of 
  Oswaldkirk 
  Hagg, 
  Ampleforth 
  

   Beacon, 
  Nunnington, 
  and 
  Canklass 
  End 
  ; 
  about 
  30 
  species 
  have 
  oc- 
  

   curred 
  to 
  Messrs. 
  Blake 
  and 
  Hudleston 
  in 
  their 
  researches 
  through 
  

   the 
  Corallian 
  beds 
  of 
  the 
  Hambleton 
  district. 
  

  

  The 
  Ho 
  warm 
  an 
  Hills. 
  

  

  This 
  fourth 
  district 
  in 
  the 
  Yorkshire 
  Corallian 
  area 
  embraces 
  the 
  

   inner 
  portion 
  of 
  the 
  range 
  of 
  hills 
  which 
  bounds 
  the 
  Yale 
  of 
  Pick- 
  

   ering 
  to 
  the 
  S.W. 
  The 
  authors 
  here 
  base 
  the 
  sequence 
  of 
  their 
  

   stratigraphical 
  succession 
  chiefly 
  on 
  palEeontological 
  grounds, 
  owing 
  

   to 
  the 
  more 
  complicated 
  nature 
  of 
  the 
  rocks 
  than 
  in 
  the 
  " 
  more 
  

   massive 
  tabular 
  range 
  " 
  to 
  the 
  north 
  and 
  north-east. 
  Less 
  attention 
  

   is 
  paid 
  by 
  them 
  to 
  the 
  petrological 
  condition 
  of 
  the 
  groups, 
  on 
  ac- 
  

   count 
  of 
  this 
  more 
  complex 
  nature 
  of 
  the 
  area. 
  

  

  The 
  authors 
  divide 
  the 
  Howardian 
  area 
  into 
  two 
  districts, 
  one 
  

   west 
  of 
  the 
  Derwent, 
  the 
  other 
  east 
  of 
  that 
  river. 
  Commencing 
  

   with 
  the 
  " 
  Lower 
  Calcareous 
  Grit 
  and 
  Passage-beds" 
  west 
  of 
  the 
  

   Derwent, 
  and 
  in 
  the 
  Park 
  quarry, 
  Castle 
  Howard, 
  the 
  presence 
  of 
  

   Ammonites 
  joerarmatus 
  shows 
  their 
  position 
  to 
  be 
  low 
  down 
  in 
  the 
  

   Lower 
  Calcareous 
  Grit. 
  Am. 
  cordatus 
  and 
  Am. 
  vertebralis 
  also 
  occur 
  

   in 
  these 
  beds 
  ; 
  it 
  is 
  the 
  horizon 
  of 
  the 
  large 
  Aptychi 
  and 
  phragmo- 
  

   cones 
  of 
  large 
  Belemnites 
  (B. 
  abbreviatus). 
  The 
  Passage-beds 
  (Middle 
  

   Grits 
  and 
  Lower 
  Limestones 
  of 
  Mr. 
  Fox 
  Strangways) 
  between 
  the 
  

   Lower 
  Calcareous 
  Grit 
  and 
  Coralline 
  Oolite, 
  containing 
  the 
  large 
  

   Trigonia 
  Meriani, 
  Pholadomyce, 
  and 
  Pecten 
  intextus, 
  here 
  receive 
  

   notice. 
  The 
  Coralline 
  Oolite 
  and 
  Coral 
  Rag 
  of 
  Malton 
  are 
  most 
  care- 
  

   fully 
  analyzed, 
  the 
  former, 
  in 
  its 
  lower 
  division, 
  holding 
  the 
  well- 
  

  

  