﻿F. 
  G. 
  H. 
  PRICE 
  ON 
  THE 
  GAULT 
  OF 
  FOLKESTONE. 
  345 
  

  

  Bed 
  I. 
  

  

  The 
  junction-bed 
  separating 
  the 
  Folkestone 
  -beds 
  of 
  the 
  Lower 
  

   Greensand 
  from 
  the 
  Gault 
  consists 
  of 
  a 
  line 
  of 
  nodules 
  of 
  sulphuret 
  

   of 
  iron, 
  which 
  is 
  about 
  1 
  foot 
  3 
  inches 
  in 
  thickness. 
  This 
  is 
  

   succeeded 
  by 
  a 
  band 
  of 
  dark 
  greensand, 
  containing 
  two 
  lines 
  of 
  

   phosphatic 
  nodules, 
  in 
  which 
  nodules 
  Ammonites 
  interruptus 
  and 
  

   pieces 
  of 
  wood 
  bored 
  by 
  Pholadidea 
  sanctce-crucis, 
  Pictet 
  et 
  Camp., 
  

   are 
  found; 
  many 
  of 
  the 
  fragments 
  of 
  Ammonites, 
  Inocerami, 
  &c. 
  

   which 
  are 
  plentiful 
  in 
  this 
  band 
  are 
  sprinkled 
  over 
  with 
  small 
  

   spicules 
  or 
  crystals 
  of 
  selenite. 
  In 
  no 
  other 
  band 
  throughout 
  the 
  

   Gault 
  has 
  this 
  ever 
  been 
  observed. 
  The 
  dark 
  greensand 
  seam 
  goes 
  

   off 
  suddenly 
  into 
  Gault, 
  with 
  a 
  line 
  of 
  phosphatic 
  nodules 
  traversing 
  it. 
  

   These 
  nodules 
  of 
  phosphate 
  of 
  lime 
  arise, 
  I 
  presume, 
  from 
  the 
  decom- 
  

   position 
  of 
  the 
  remains 
  of 
  mollusca, 
  fish, 
  saurians, 
  &c. 
  

  

  The 
  fossils 
  of 
  this 
  junction-bed 
  are 
  usually 
  in 
  the 
  condition 
  of 
  

   rolled 
  casts, 
  and 
  of 
  a 
  fragmentary 
  nature. 
  The 
  following 
  are 
  some 
  

   of 
  the 
  most 
  ordinary 
  forms 
  met 
  with 
  : 
  — 
  

  

  Palaeocorystes 
  Stokesii, 
  Mant. 
  

  

  Inocerarnus 
  concentricus, 
  Park. 
  

  

  Nucula 
  pectinata, 
  Sow. 
  

  

  Pecten, 
  sp. 
  

  

  Pholadidea 
  sanctas-crucis, 
  Pict. 
  et 
  Camp., 
  in 
  wood. 
  

  

  Teredo-tubes. 
  

  

  Trigonia 
  Fittoni, 
  Besh. 
  

  

  Dentalium 
  decussatum, 
  Sow. 
  

  

  Pyrula, 
  sp. 
  

  

  Ammonites 
  interruptus, 
  Brug. 
  

  

  Hamites 
  attenuatus, 
  Sow. 
  

  

  H. 
  rotundus, 
  Sow. 
  

  

  Belemnites 
  minimus, 
  List. 
  

  

  Nautilus, 
  sp. 
  

  

  Vertebrae 
  of 
  saurians 
  and 
  fish. 
  

  

  Mr. 
  Gardner 
  has 
  obtained 
  a 
  species 
  of 
  Hippurites 
  and 
  Buccinum 
  

   gaultinum 
  from 
  this 
  bed. 
  

  

  The 
  above-mentioned 
  fossils 
  are 
  mostly 
  found 
  more 
  or 
  less 
  in- 
  

   crusted 
  with 
  phosphate. 
  

  

  Upon 
  many 
  pieces 
  of 
  Ammonites, 
  nearly 
  all 
  of 
  which 
  are 
  Ammonites 
  

   interruptus, 
  I 
  have 
  found 
  specimens 
  of 
  Plicatula 
  pectinoides, 
  Pecten 
  

   quinquecostatus, 
  Trocliosmilia 
  sulcata, 
  and 
  a 
  species 
  of 
  Nucula 
  allied 
  

   to 
  obtusa, 
  all 
  with 
  the 
  shell 
  on, 
  apparently 
  indicating 
  that 
  they 
  were 
  

   contemporary 
  with 
  the 
  formation 
  of 
  the 
  bed, 
  which 
  appears 
  to 
  have 
  

   been 
  derived 
  from 
  some 
  deposit 
  now 
  destroyed. 
  

  

  Whilst 
  examining 
  this 
  bed 
  last 
  October 
  at 
  Copt 
  Point, 
  I 
  met 
  with 
  

   a 
  piece 
  of 
  Ammonites 
  Roissyanus, 
  D'Orb., 
  in 
  situ, 
  imbedded 
  in 
  phos- 
  

   phate 
  ; 
  this 
  is 
  a 
  very 
  rare 
  Ammonite 
  to 
  meet 
  with 
  at 
  all, 
  and 
  

   especially 
  in 
  the 
  Lower 
  Gault, 
  as 
  it 
  belongs 
  to 
  the 
  Cristati, 
  or 
  

   crested 
  group 
  of 
  Ammonites, 
  which 
  are 
  characteristic 
  of 
  the 
  Upper 
  

   Gault. 
  

  

  I 
  also 
  found 
  a 
  fragment 
  of 
  a 
  very 
  large 
  smooth 
  Ammonite, 
  deeply 
  

   grooved, 
  which 
  I 
  cannot 
  at 
  present 
  assign 
  to 
  any 
  species. 
  

  

  