﻿COTTESWOLD, 
  M1DFOKD, 
  AND 
  YEOVIL 
  SANDS, 
  ETC. 
  471 
  

  

  Sands,"' 
  which 
  is 
  erroneous, 
  and 
  the 
  merging 
  of 
  these 
  two 
  divisions 
  

   into 
  one 
  — 
  Lower 
  Toarcian 
  * 
  — 
  with 
  perhaps 
  a 
  marginal 
  note 
  as 
  to 
  the 
  

   position 
  of 
  " 
  the 
  Sands" 
  in 
  the 
  various 
  localities. 
  

  

  On 
  the 
  other 
  hand, 
  the 
  Murchisonce- 
  and 
  Concavum-zoiies 
  in 
  

   Gloucestershire, 
  from 
  the 
  Pea-grit, 
  or 
  perhaps 
  from 
  the 
  Lower 
  Lime- 
  

   stone, 
  to 
  the 
  Gryphite-grit, 
  would 
  form 
  the 
  " 
  Upper 
  Toarcian'" 
  and 
  

   this 
  horizon 
  might 
  be 
  marked 
  as 
  g 
  4. 
  Wherever 
  the 
  Upper 
  

   Trigonia-grit 
  (Par 
  Jcinsoni- 
  zone) 
  is 
  absent 
  in 
  the 
  Cotteswolds 
  would 
  

   be 
  Upper 
  Toarcian 
  and 
  would 
  cause 
  considerable 
  alteration. 
  

   Part 
  of 
  Cleeve 
  Hill, 
  part 
  of 
  the 
  district 
  round 
  Andoversford, 
  part 
  of 
  

   Leckhampton 
  Hill, 
  Crickley 
  Hill, 
  part 
  of 
  Birdlip 
  Hill, 
  part 
  of 
  

   Haresfield 
  and 
  Procester 
  Hills, 
  and, 
  in 
  fact, 
  most 
  of 
  the 
  outer 
  edge 
  

   of 
  the 
  escarpment 
  would 
  be 
  Upper 
  Toarcian. 
  Part 
  of 
  the 
  country 
  

   round 
  Corton 
  Downs, 
  in 
  Somerset, 
  and 
  some 
  part 
  of 
  the 
  escarpment 
  

   as 
  it 
  passes 
  along, 
  now 
  in 
  Somerset, 
  and 
  now 
  in 
  Dorset, 
  would 
  also 
  

   be 
  distinguished 
  as 
  Upper 
  Toarcian. 
  

  

  I 
  may 
  just 
  say 
  a 
  word 
  concerning 
  the 
  Northampton 
  Sands, 
  and 
  

   the 
  sands 
  below 
  the 
  Yorkshire 
  Dogger. 
  Although 
  partly 
  on 
  the 
  

   same 
  horizon 
  as 
  the 
  strata 
  which 
  have 
  been 
  mapped 
  as 
  " 
  Midford 
  

   Sands," 
  these 
  sands 
  have 
  been 
  mapped 
  separately. 
  Part 
  of 
  the 
  

   Northampton 
  Sand, 
  however 
  — 
  that 
  round 
  Duston 
  — 
  belongs 
  to 
  the 
  

   Opalinum-zone, 
  as 
  I 
  have 
  been 
  able 
  to 
  determine 
  by 
  an 
  inspection 
  of 
  

   its 
  Ammonites 
  f. 
  Mr. 
  Thompson 
  J 
  has 
  attempted 
  to 
  show 
  that 
  the 
  

   Upper 
  Leda-ovum-be&s 
  upon 
  which 
  this 
  rests 
  — 
  the 
  top 
  of 
  the 
  Upper 
  

   Lias 
  Clay 
  of 
  the 
  district 
  — 
  belong 
  to 
  the 
  Jurense-zone. 
  I 
  should 
  be 
  

   glad 
  to 
  admit 
  this, 
  if 
  possible, 
  as 
  it 
  would 
  be 
  an 
  additional 
  argument 
  

   against 
  the 
  artifical 
  definition 
  of 
  the 
  " 
  Midford 
  Sands 
  " 
  as 
  equal 
  to 
  

   the 
  Opalinwn- 
  and 
  Jurense-zones 
  ; 
  but 
  I 
  am 
  unable 
  to 
  do 
  so. 
  The 
  

   species 
  of 
  Ammonites 
  which 
  he 
  quotes 
  (p. 
  83) 
  from 
  the 
  Upper 
  

   Leda-ovum 
  beds 
  are 
  all 
  characteristic 
  of 
  the 
  Commune-zone 
  ; 
  none 
  of 
  

   the 
  characteristic 
  Jiwense-zoiie 
  species 
  are 
  mentioned 
  — 
  not 
  a 
  single 
  

   species 
  of 
  the 
  genus 
  Grammoceras 
  which 
  dominated 
  that 
  period. 
  

   The 
  Dogger 
  Sands 
  of 
  Yorkshire 
  overlie 
  the 
  Striatidum-'be&s. 
  From 
  

   au 
  examination 
  of 
  some 
  species 
  of 
  Ammonites 
  kindly 
  forwarded 
  to 
  

   me 
  by 
  Mr. 
  Hudleston, 
  I 
  am 
  able 
  to 
  confirm 
  his 
  view 
  that 
  they, 
  in 
  

   part 
  at 
  any 
  rate, 
  belong 
  to 
  the 
  Opalinnm-zQxiz 
  ; 
  and 
  in 
  part 
  they 
  

   represent 
  the 
  JDumortieria-beds. 
  It 
  would 
  be 
  correct, 
  looking 
  at 
  

   their 
  zonal 
  and 
  stratigraphical 
  affinities, 
  to 
  place 
  together 
  the 
  

   Yeovil 
  and 
  the 
  Dogger 
  Sands 
  under 
  one 
  name 
  — 
  far 
  more 
  correct 
  than 
  

   to 
  combine 
  the 
  former 
  with 
  the 
  Cotteswold 
  and 
  Midford 
  Sands. 
  

   Both 
  the 
  Yeovil 
  and 
  the 
  Dogger 
  Sands 
  occupy 
  a 
  similar 
  horizon, 
  

   nameiy 
  above 
  the 
  Striatulum-he&s 
  and 
  below 
  the 
  Murchisonce-zone 
  ; 
  

   while 
  the 
  Cotteswold 
  Sands 
  are 
  below 
  the 
  Striatidum-heds. 
  Accord- 
  

   ing 
  to 
  the 
  present 
  proposed 
  classification, 
  the 
  Yorkshire 
  Oolites 
  up 
  

  

  * 
  The 
  tops 
  of 
  Ham 
  Hill 
  and 
  Chiselborough 
  Hill 
  in 
  Somerset 
  — 
  at 
  present 
  

   marked 
  g 
  5, 
  Inferior 
  Oolite, 
  and 
  which 
  ought, 
  at 
  least, 
  to 
  have 
  been 
  marked 
  g 
  4, 
  

   '•Midford 
  Sands," 
  the 
  same 
  as 
  the 
  sands 
  with 
  shelly 
  beds 
  at 
  Stoford, 
  Babylon 
  Hill, 
  

   Bradford 
  Abbas, 
  &c., 
  which 
  are 
  on 
  the 
  same 
  horizon 
  — 
  would 
  be 
  marked 
  as 
  

   Lower 
  Toarcian. 
  

  

  t 
  "Inferior-Oolite 
  Ammonites," 
  p. 
  52. 
  Palseont. 
  Soc. 
  1888. 
  

  

  \ 
  "The 
  Upper 
  Lias 
  of 
  Northampton: 
  Part 
  VI.," 
  Journal 
  of 
  the 
  North- 
  

   amptonshire 
  Natural 
  History 
  Field 
  Club, 
  p. 
  54 
  (1888). 
  

  

  