﻿Vol. 
  53.] 
  THE 
  CEETACEOTJS 
  STKATA 
  OF 
  COUNTY 
  ANTEIM. 
  591 
  

  

  lower 
  A. 
  inflatus-zone, 
  while 
  in 
  the 
  easternmost 
  localities 
  the 
  true 
  

   Cenomanian 
  conditions 
  are 
  foreshadowed, 
  the 
  corals 
  and 
  sea-urchins 
  

   also 
  occurring 
  only 
  in 
  the 
  latter. 
  

  

  Chloritic 
  Sands 
  and 
  Sandstones. 
  

  

  These 
  beds 
  present 
  a 
  difficult 
  problem, 
  the 
  differences 
  between 
  

   the 
  Central 
  and 
  Eastern 
  Divisions 
  being 
  extremely 
  marked. 
  (Wood- 
  

   burn 
  Glen, 
  in 
  its 
  characters 
  and 
  relations, 
  must 
  now 
  be 
  included 
  in 
  

   the 
  Eastern 
  Division; 
  in 
  the 
  previous 
  cases 
  it 
  occupied 
  an 
  inter- 
  

   mediate 
  position 
  between 
  the 
  two 
  types.) 
  

  

  Tate 
  remarks 
  : 
  — 
  ' 
  The 
  Chloritic 
  Sands 
  and 
  Sandstones 
  have, 
  on 
  

   the 
  whole, 
  a 
  fauna 
  possessing 
  an 
  Upper 
  Greensand 
  facies, 
  many 
  

   species, 
  however, 
  pointing 
  to 
  higher 
  zones. 
  It 
  is 
  very 
  probable 
  

   that 
  the 
  Chloritic 
  Sands 
  of 
  "Woodburn 
  (the 
  zone 
  of 
  Inoceramus 
  

   Crispin) 
  may 
  be 
  inferior 
  to 
  the 
  Chloritic 
  Sandstones 
  of 
  Colin 
  Glen, 
  

   the 
  zone 
  of 
  Eocogyra 
  columba. 
  These 
  zones, 
  however, 
  never 
  come 
  

   into 
  contact.' 
  

  

  Barrois 
  concludes 
  that, 
  as 
  all 
  the 
  fossils 
  obtained 
  in 
  these 
  beds 
  

   were 
  Turonian, 
  these 
  strata 
  must 
  be 
  considered 
  as 
  belonging 
  to 
  that 
  

   stage, 
  and 
  refers 
  them 
  to 
  the 
  zones 
  of 
  Terebratulina 
  gracilis 
  and 
  

   Holaster 
  planus. 
  

  

  The 
  zone 
  of 
  Eocogyra 
  columba 
  is 
  characteristic 
  of 
  the 
  Central, 
  the 
  

   Inoceramus-zone 
  of 
  the 
  Eastern 
  district, 
  and 
  the 
  former 
  will 
  be 
  

   first 
  dealt 
  with. 
  

  

  Central 
  Division. 
  (Zone 
  of 
  Exogyra 
  columba.) 
  

  

  These 
  sands 
  and 
  sandstones, 
  often 
  of 
  a 
  greenish-yellow 
  colour, 
  

   are 
  well 
  developed 
  in 
  this 
  Division, 
  attaining 
  a 
  thickness 
  of 
  nearly 
  

   20 
  feet 
  at 
  Colin 
  Glen. 
  In 
  the 
  Eastern 
  Division, 
  however, 
  they 
  are 
  

   of 
  rare 
  occurrence, 
  being 
  represented 
  by 
  yellow-green 
  sands 
  4 
  feet 
  

   thick 
  at 
  Barney's 
  Point, 
  in 
  Islandmagee, 
  where 
  the 
  two 
  zones 
  

   mentioned 
  by 
  Tate 
  are 
  in 
  contact, 
  and 
  it 
  is 
  seen 
  that 
  the 
  Exogyra 
  

   columba 
  is 
  the 
  lower 
  of 
  the 
  two. 
  

  

  Gault 
  has 
  added 
  a 
  considerable 
  number 
  of 
  species, 
  which 
  have 
  

   not 
  come 
  under 
  our 
  notice. 
  1 
  

  

  As 
  I 
  have 
  already 
  remarked, 
  Orbitolina 
  concava 
  and 
  JRhyncJio- 
  

   nella 
  Schloenbachi 
  characterize 
  Bed 
  9 
  of 
  Meyer 
  (which 
  he 
  still 
  

   includes 
  in 
  the 
  Upper 
  Greensand), 
  and 
  the 
  latter 
  does 
  not 
  extend 
  

   beyond 
  his 
  Bed 
  12. 
  Ostrea 
  carinata, 
  Lam., 
  Pecten 
  asper, 
  Lam., 
  

   Cucullcea 
  ligeriensis 
  (d'Orb.), 
  Trigonia 
  crenulata, 
  Lam., 
  Oxyrhina 
  

   Mantelli, 
  Ag., 
  Ptyclwdus 
  decurrens, 
  Ag., 
  and 
  Callianassa 
  are 
  

   limited 
  in 
  the 
  same 
  manner 
  in 
  Devon, 
  and 
  most 
  of 
  these 
  are 
  

   found 
  only 
  in 
  Beds 
  10 
  and 
  11. 
  Barrois 
  also 
  observed 
  the 
  Orbito- 
  

   lina- 
  and 
  Rhynchonella 
  ScTilcenbacJii-be&s 
  in 
  Devon, 
  overlain 
  by 
  a 
  

   fauna 
  in 
  part 
  similar 
  to 
  the 
  above, 
  accompanied 
  by 
  Ammonites 
  

   [Acanihoceras] 
  Mantelli 
  (Sow.) 
  and 
  A. 
  Coupei 
  (Brongn.), 
  and 
  

   regarded 
  them 
  as 
  of 
  Warminster 
  age. 
  2 
  It 
  is 
  therefore 
  evident 
  

   that 
  the 
  Exogyra 
  columba- 
  zone 
  has 
  a 
  strong 
  Lower 
  Cenomanian 
  

  

  1 
  Proc. 
  Belfast 
  Nat. 
  Field-Club, 
  n. 
  s. 
  vol. 
  i. 
  (1877), 
  p. 
  258. 
  

  

  2 
  ' 
  Kecherches 
  sur 
  le 
  Terrain 
  Cretace 
  Superieur, 
  etc.,' 
  p. 
  70. 
  

  

  