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  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  ranges 
  from 
  the 
  Inferior 
  Oolite 
  to 
  the 
  Corallian 
  rocks. 
  G. 
  scabrosa 
  

   is 
  entirely 
  confined 
  to 
  the 
  Cornbrash, 
  and 
  is 
  a 
  Yorkshire 
  form. 
  

  

  Briozoa. 
  — 
  Berenicea 
  diluviana, 
  B. 
  luciensis, 
  Hippothoa 
  Smithii, 
  

   Spiropora 
  straminea, 
  and 
  Stomatopora 
  dichotoma 
  are 
  the 
  4 
  genera 
  

   and 
  5 
  species 
  that 
  occur 
  in 
  the 
  Cornbrash. 
  Hipjjothoa 
  Smithii 
  is 
  the 
  

   only 
  species 
  truly 
  belonging 
  to 
  this 
  horizon. 
  The 
  other 
  4 
  named 
  

   species 
  reach 
  the 
  Cornbrash 
  from 
  lower 
  beds. 
  19 
  genera 
  and 
  51 
  

   species 
  in 
  all 
  occur 
  in 
  the 
  Jurassic 
  rocks. 
  31 
  species 
  are 
  in 
  the 
  

   Great 
  Oolite, 
  17 
  in 
  the 
  Inferior 
  Oolite. 
  

  

  Brachiopoda. 
  — 
  Terebratula 
  with 
  5 
  species, 
  Waldheimia 
  with 
  8, 
  

   Wiynchonella 
  with 
  5, 
  and 
  Discina 
  with 
  1, 
  comprise 
  all 
  that 
  are 
  known 
  

   in 
  the 
  Cornbrash. 
  Waldheimia 
  obovata, 
  W. 
  ornithocephala, 
  Tere- 
  

   bratula 
  coarctata, 
  T. 
  intermedia, 
  and 
  T. 
  obovata, 
  = 
  §, 
  pass 
  to 
  the 
  

   Kellaways 
  Rock 
  ; 
  no 
  Lower 
  Oolite 
  form 
  passes 
  to 
  any 
  higher 
  

   horizon. 
  

  

  Lamellibranchiata. 
  Monomyaria. 
  — 
  11 
  genera 
  and 
  55 
  species 
  

   occur, 
  chiefly 
  made 
  up 
  of 
  species 
  belonging 
  to 
  the 
  genera 
  Avicida 
  

   (6 
  species), 
  Gervillia 
  (5), 
  Lima 
  (8), 
  Ostrea 
  (8), 
  and 
  Pecten 
  (16) 
  ; 
  

   the 
  remaining 
  6 
  genera 
  number 
  but 
  few 
  species. 
  7 
  genera 
  and 
  

   14 
  species 
  pass 
  to 
  the 
  Kellaways 
  Hock 
  ; 
  and 
  the 
  same 
  number 
  bridge 
  

   over 
  the 
  change 
  occurring 
  between 
  the 
  Forest 
  Marble 
  and 
  Corn- 
  

   brash, 
  so 
  that 
  the 
  peculiar 
  or 
  confined 
  species 
  are 
  few. 
  Those 
  that 
  

   pass 
  direct 
  to 
  the 
  Kellaways 
  Rock 
  are 
  Avicula 
  braamburiensis, 
  Ger- 
  

   villia 
  aviculoides, 
  Lima 
  duplicata, 
  L. 
  pectiniformis, 
  Ostrea 
  Jlabelloides, 
  

   0. 
  JSoiverbyi, 
  Pecten 
  annulatus, 
  P. 
  armatus, 
  P. 
  demissus, 
  P. 
  Jibrosus, 
  

   P. 
  inovquicostatus, 
  P. 
  lens, 
  P. 
  vagans, 
  Perna 
  rugosa, 
  and 
  Placunopsis 
  

   in&qualis. 
  The 
  only 
  restricted 
  species, 
  so 
  far 
  as 
  we 
  know, 
  are 
  

   Hinnites 
  gradus, 
  H. 
  gradatus, 
  Lima 
  helvetica, 
  L. 
  rigidula, 
  Ostrea 
  

   spatiosa, 
  Pecten 
  anisopleurus, 
  P. 
  cingulatus, 
  and 
  P. 
  rushdenensis. 
  

   Only 
  3 
  of 
  the 
  genera 
  pass 
  to 
  the 
  Oxford 
  Clay 
  — 
  Gervillia, 
  Lima, 
  and 
  

   Pecten 
  (Gervillia 
  aviculoides, 
  Lima 
  duplicata, 
  L. 
  pectiniformis, 
  Pecten 
  

   annulatus, 
  P. 
  arenatus, 
  P. 
  demissus, 
  P. 
  Jibrosus, 
  P. 
  lens, 
  and 
  P. 
  

   vagans). 
  4 
  genera 
  with 
  13 
  species 
  pass 
  to 
  the 
  Coral 
  Rag 
  or 
  Coral- 
  

   lian 
  beds. 
  

  

  Dimyaria. 
  — 
  33 
  genera 
  and 
  98 
  species 
  range 
  through 
  England. 
  

   Pholadomya 
  and 
  Trigonia 
  are 
  the 
  only 
  two 
  largely 
  represented 
  

   genera, 
  the 
  former 
  by 
  10 
  species, 
  the 
  latter 
  by 
  13. 
  Modiola, 
  Myacites, 
  

   Astarte, 
  and 
  Cardium 
  have 
  7 
  species 
  each. 
  14 
  genera 
  yield 
  only 
  1 
  

   species 
  each 
  ; 
  and 
  11 
  only 
  2. 
  Either 
  want 
  of 
  research 
  or 
  extreme 
  

   rarity 
  (which 
  is 
  hardly 
  probable) 
  must 
  account 
  for 
  the 
  paucity 
  of 
  

   individuals. 
  The 
  Cornbrash 
  receives 
  from 
  the 
  Eorest 
  Marble 
  

   11 
  genera 
  and 
  19 
  species 
  ; 
  and 
  12 
  genera 
  and 
  27 
  species 
  pass 
  to 
  the 
  

   succeeding 
  Kellaways 
  Rock. 
  Only 
  8 
  genera 
  and 
  12 
  species 
  are 
  

   strictly 
  confined 
  to 
  the 
  Cornbrash 
  ; 
  and 
  8 
  genera 
  and 
  16 
  species 
  first 
  

   appear 
  in 
  it. 
  Those 
  strictly 
  confined 
  to 
  the 
  Cornbrash, 
  so 
  far 
  as 
  we 
  

   at 
  present 
  know, 
  are 
  : 
  — 
  Astarte 
  Leclcenbyi, 
  Cardium 
  latum, 
  Leda 
  

   rostralis, 
  L. 
  variabilis, 
  Lucina 
  Beanii, 
  Myacites 
  uniformis, 
  Opis 
  

   Leckenbyi, 
  0. 
  scarburgensis, 
  Sanguinolaria 
  parvida, 
  Trigonia 
  cas- 
  

   siope, 
  T. 
  scarburgensis, 
  and 
  T. 
  tripartita. 
  

  

  Although 
  the 
  Cornbrash 
  makes 
  no 
  physical 
  or 
  stratigraphical 
  

  

  