﻿F. 
  G. 
  H. 
  PRICE 
  ON 
  THE 
  GAT/LT 
  OF 
  FOLKESTONE. 
  351 
  

  

  collected 
  as 
  many 
  as 
  240 
  species, 
  marking 
  their 
  particular 
  horizon 
  

   on 
  the 
  table 
  of 
  genera 
  and 
  species 
  at 
  the 
  end 
  of 
  this 
  paper, 
  it 
  will 
  be 
  

   seen 
  that 
  124 
  forms 
  become 
  extinct 
  in 
  bed 
  No. 
  VIII., 
  and 
  39 
  forms 
  

   are 
  continued 
  into 
  the 
  Upper 
  Gault. 
  Bed 
  VIII., 
  besides 
  containing 
  

   the 
  limit-fauna, 
  possesses 
  as 
  many 
  as 
  18 
  species 
  which 
  are 
  peculiar 
  

   to 
  it. 
  59 
  new 
  forms 
  occur 
  in 
  the 
  Upper 
  Gault, 
  making 
  their 
  first 
  

   appearance 
  either 
  in 
  No. 
  VIII. 
  or 
  in 
  a 
  higher 
  zone. 
  

  

  The 
  following 
  is 
  a 
  list 
  of 
  fossils 
  which 
  may 
  be 
  considered 
  peculiar 
  

   to 
  bed 
  VIII. 
  :— 
  

  

  Bathycyathus 
  Sowerbyi, 
  Edw. 
  § 
  H. 
  Ammonites 
  splendens, 
  Sow. 
  (a 
  variety). 
  

  

  Vermicularia, 
  sp. 
  Beudanti, 
  Brongn. 
  

  

  Avicula, 
  sp. 
  Brongniartianus 
  ? 
  Pictet. 
  

  

  Cucullsea 
  glabra, 
  Park. 
  Itierianus,!)' 
  Orb. 
  

  

  Cyprina 
  quadrata, 
  If 
  Orb. 
  Selliguinus, 
  Brongn. 
  

  

  Mytilus 
  Galliennei, 
  B'Orb. 
  Pachyrhizodus 
  glyphodus, 
  Blake 
  8[ 
  

   Pholas, 
  n. 
  sp. 
  Mackie. 
  

  

  Rhodani, 
  Plot, 
  et 
  Camp. 
  Ptychodus, 
  sp. 
  

  

  Scalaria 
  gaultina, 
  D' 
  Orb. 
  Fish-jaw 
  and 
  fish-teeth, 
  undescribed. 
  

   Murex 
  calcar, 
  Sow. 
  

  

  In 
  addition 
  to 
  the 
  above 
  a 
  variety 
  of 
  Ammonites 
  tuberculatus, 
  Sow. 
  

   is 
  met 
  with. 
  

  

  This 
  bed 
  may 
  be 
  considered 
  the 
  zone 
  of 
  Ammonites 
  cristatus. 
  

  

  Bed 
  IX. 
  

  

  This 
  bed, 
  forming 
  the 
  base 
  of 
  the 
  Upper 
  Gault, 
  is 
  measured 
  from 
  

   the 
  line 
  of 
  nodules 
  at 
  the 
  top 
  of 
  the 
  last-described 
  bed 
  to 
  a 
  line 
  of 
  

   nodules 
  containing 
  vast 
  quantities 
  of 
  crushed 
  forms 
  of 
  Inoceramus 
  

   sulcatus 
  ; 
  its 
  total 
  thickness 
  is 
  9 
  feet 
  4| 
  inches. 
  

  

  Inoceramus 
  sulcatus 
  is 
  the 
  most 
  characteristic 
  fossil 
  of 
  this 
  bed, 
  

   which 
  is 
  everywhere 
  marked 
  with 
  its 
  silvery 
  impressions. 
  This 
  

   species 
  has 
  never 
  been 
  met 
  with 
  in 
  the 
  Lower 
  Gault 
  at 
  all, 
  with 
  the 
  

   exception 
  of 
  a 
  rolled 
  cast 
  recorded 
  * 
  as 
  being 
  found 
  by 
  Mr. 
  Etheridge 
  

   some 
  years 
  ago 
  in 
  the 
  junction-bed 
  I. 
  In 
  the 
  middle 
  junction- 
  

   bed, 
  No. 
  VIII. 
  , 
  it 
  appears 
  frequently, 
  and 
  occurs 
  in 
  good 
  condi- 
  

   tion 
  ; 
  but 
  it 
  reaches 
  its 
  maximum 
  of 
  development 
  in 
  the 
  bed 
  

   now 
  under 
  consideration, 
  beyond 
  which 
  it 
  does 
  not 
  pass. 
  At 
  a 
  

   distance 
  of 
  one 
  foot 
  above 
  the 
  nodule-bed 
  there 
  occurs 
  a 
  seam 
  of 
  

   very 
  hard 
  marly 
  Gault, 
  which 
  is 
  filled 
  with 
  specimens 
  of 
  this 
  

   fossil. 
  

  

  A 
  hybrid 
  form 
  of 
  this 
  Inoceramus 
  is 
  met 
  with 
  in 
  this 
  zone, 
  half 
  

   of 
  the 
  shell 
  resembling 
  I. 
  sulcatus, 
  and 
  half 
  i~. 
  concentricus. 
  It 
  was 
  

   named 
  Inoceramus 
  subsulcatus 
  by 
  the 
  Rev. 
  Thomas 
  Wiltshirefj 
  and 
  

   is 
  figured 
  by 
  Pictet 
  et 
  Eoux, 
  Gres 
  Verts, 
  pi. 
  42. 
  fig. 
  1. 
  

  

  Ammonites 
  varicosus, 
  Sow., 
  is 
  another 
  fossil 
  met 
  with 
  in 
  great 
  

   abundance 
  in 
  this 
  zone, 
  and 
  is 
  decidedly 
  the 
  characteristic 
  Am- 
  

   monite 
  of 
  the 
  bed 
  ; 
  it 
  makes 
  its 
  first 
  appearance 
  in 
  the 
  line 
  of 
  

  

  * 
  Memoirs 
  of 
  the 
  Geological 
  Survey, 
  ' 
  The 
  Geology 
  of 
  the 
  country 
  between 
  

   Folkestone 
  and 
  Rye.' 
  

  

  t 
  " 
  On 
  the 
  chalk 
  of 
  Hunstanton," 
  by 
  the 
  Rev. 
  Thomas 
  Wiltshire, 
  Quart. 
  

   Journ. 
  Geol. 
  Soc. 
  vol. 
  xxv. 
  p. 
  190 
  (1869). 
  

  

  