﻿558 
  DR. 
  W. 
  FEASER 
  HUME 
  ON 
  [Dec. 
  1 
  89 
  7, 
  

  

  cavities 
  in 
  this 
  rock 
  have 
  been 
  drawn 
  out 
  parallel 
  to 
  the 
  direction 
  

   of 
  flow, 
  and 
  zeolites 
  have 
  been 
  abundantly 
  formed 
  in 
  the 
  vesicles. 
  

   A 
  quarter 
  of 
  a 
  mile 
  to 
  the 
  north-east, 
  a 
  little 
  south 
  of 
  Cloghfin 
  

   Harbour, 
  the 
  Cretaceous 
  rocks 
  are 
  well 
  exposed 
  on 
  the 
  shore, 
  

   especially 
  at 
  low 
  tides. 
  The 
  beds 
  dip 
  S.W. 
  at 
  an 
  angle 
  of 
  about 
  5°, 
  

   and 
  every 
  member 
  of 
  the 
  series 
  is 
  clearly 
  visible. 
  The 
  order 
  of 
  

   succession 
  is 
  as 
  follows, 
  commencing 
  from 
  the 
  top 
  : 
  — 
  

  

  1. 
  Compact 
  limestone, 
  crowded 
  with 
  green 
  sponge-nodules 
  

   6 
  inches 
  thick. 
  This 
  band 
  forms 
  the 
  summit 
  of 
  a 
  low 
  platform, 
  

   which 
  gradually 
  slopes 
  south-westward, 
  and 
  is 
  undoubtedly 
  the 
  same 
  

   as 
  that 
  previously 
  mentioned 
  as 
  occurring 
  on 
  the 
  shore 
  at 
  White- 
  

   head. 
  

  

  2. 
  Limestone, 
  much 
  jointed, 
  and 
  readily 
  breaking 
  into 
  flakes 
  

   an 
  inch 
  or 
  more 
  thick, 
  characterized, 
  as 
  in 
  the 
  previous 
  case, 
  by 
  the 
  

   great 
  abundance 
  of 
  sponge-remains, 
  these 
  forming 
  a 
  particularly 
  

   well-marked 
  layer 
  at 
  the 
  base. 
  The 
  species 
  are 
  the 
  same 
  as 
  those 
  

   mentioned 
  above, 
  Ventriculites 
  cribrosus, 
  Phil., 
  and 
  Etheridgia 
  

   mirabilis, 
  Tate, 
  being 
  especially 
  characteristic. 
  Total 
  thickness 
  

   = 
  3| 
  feet. 
  

  

  3. 
  The 
  Chloritic 
  Chalk 
  and 
  Sands 
  are 
  well 
  exposed 
  in 
  a 
  low 
  

   cliff 
  running 
  parallel 
  to 
  the 
  strike 
  of 
  the 
  beds, 
  the 
  summit 
  of 
  which 
  

   is 
  formed 
  by 
  the 
  base 
  of 
  the 
  Spongiarian 
  zone 
  above-mentioned. 
  

   In 
  the 
  upper 
  part, 
  which 
  is 
  really 
  a 
  glauconitic 
  limestone, 
  Echino- 
  

   corys 
  gibbus, 
  Lam., 
  is 
  abundant. 
  Other 
  fossils 
  obtained 
  by 
  us 
  at 
  

   this 
  level 
  were 
  Parasmilia 
  centralis, 
  Mant., 
  Bourgueticrinus 
  (portions 
  

   of 
  stem), 
  Claris-spines, 
  probably 
  C. 
  sceptrifera, 
  Mant., 
  Terebratula 
  

   carnea, 
  Sow., 
  Spondylus 
  spinosus, 
  Sow., 
  Exogyra 
  near 
  plicata, 
  

   Inoceramus-fragments, 
  and 
  numerous 
  sponges. 
  Total 
  thickness 
  

   =3 
  feet. 
  

  

  4. 
  At 
  this 
  point 
  a 
  band 
  of 
  Serpula 
  filiformis 
  is 
  easily 
  recognizable. 
  

   The 
  lower 
  part 
  of 
  the 
  cliff 
  is 
  less 
  fossiliferous, 
  though 
  three 
  

   Inoceramus-b&n&s 
  are 
  well-marked, 
  the 
  lowest, 
  2 
  feet 
  8 
  inches 
  from 
  

   the 
  Serpida-l&yer, 
  being 
  composed 
  of 
  larger 
  fragments. 
  Numerous 
  

   branching 
  forms, 
  apparently 
  of 
  polyzoan 
  nature, 
  are 
  present 
  at 
  

   this 
  level, 
  and 
  a 
  little 
  below 
  it 
  I 
  obtained 
  an 
  example 
  of 
  Galeri{es 
  

   albogalerus, 
  var. 
  angulosus, 
  Desor. 
  

  

  5. 
  The 
  remaining 
  2 
  feet 
  6 
  inches 
  consists 
  of 
  soft 
  glauconitic 
  

   sands, 
  which, 
  with 
  the 
  above 
  exception, 
  did 
  not 
  yield 
  fossils. 
  

   The 
  base 
  of 
  these 
  beds 
  is 
  hidden 
  by 
  pebbles 
  and 
  seaweed, 
  but 
  the 
  

   thickness 
  of 
  the 
  strata 
  thus 
  obscured 
  must 
  be 
  at 
  least 
  4 
  feet, 
  

   calculated 
  by 
  pacing. 
  

  

  6. 
  The 
  Yellow 
  Sandstones 
  and 
  Marls 
  (cropping 
  out 
  in 
  a 
  

   step-like 
  manner, 
  the 
  latter 
  being 
  more 
  rapidly 
  denuded) 
  are 
  here 
  some 
  

   8 
  feet 
  thick, 
  and 
  consist 
  of 
  alternating 
  strata 
  of 
  compact 
  calcareous 
  

   sandstone 
  and 
  softer 
  marls. 
  In 
  the 
  latter 
  iron-pyrites 
  nodules 
  are 
  

   not 
  uncommon, 
  and 
  in 
  the 
  sandstone-bands 
  are 
  many 
  peculiar 
  dark 
  

   branching 
  bodies, 
  occasionally 
  divided 
  into 
  several 
  segments. 
  High 
  

   up 
  in 
  the 
  series 
  occur 
  large 
  specimens 
  of 
  Pecten 
  \_Janira] 
  quadri- 
  

   costatus, 
  Sow., 
  while 
  Vermicularia 
  concava, 
  Sow., 
  and 
  V. 
  quinque- 
  

   carinata, 
  Rom., 
  are 
  very 
  abundant. 
  These 
  species 
  of 
  Vermicularia 
  

  

  