﻿PROF. 
  C. 
  LAPWORTH 
  ON" 
  THE 
  GIRVAN 
  SUCCESSION. 
  583 
  

  

  greyish-yellow 
  shales 
  crowded 
  with 
  casts 
  of 
  fossils 
  of 
  the 
  genera 
  

   Encrinurus, 
  Ampyx, 
  Trinucleus, 
  Leptcena, 
  Strophomena, 
  Orthis, 
  and 
  

   Gythere. 
  

  

  Above 
  these 
  we 
  find 
  traces 
  of 
  the 
  usual 
  nodule-bearing 
  con- 
  

   glomerate. 
  

  

  These 
  fossiliferous 
  shales 
  are 
  truncated 
  at 
  an 
  acute 
  angle 
  by 
  the 
  

   strike-fault 
  which 
  runs 
  along 
  the 
  axis 
  of 
  the 
  synclinal 
  between 
  the 
  

   two 
  limestone-quarries. 
  On 
  the 
  opposite 
  side 
  of 
  the 
  fault 
  we 
  find 
  

   the 
  more 
  muddy 
  and 
  concretionary 
  Maclurea- 
  and 
  coral-beds. 
  The 
  

   tramway 
  and 
  grassy 
  slopes 
  below 
  hide 
  the 
  main 
  mass 
  of 
  these 
  

   from 
  sight 
  ; 
  but 
  when 
  we 
  search 
  the 
  roadway 
  beneath 
  we 
  find 
  evi- 
  

   dence 
  that 
  they 
  have 
  in 
  turn 
  been 
  underlain 
  by 
  green 
  and 
  purple 
  

   sandstones, 
  more 
  or 
  less 
  pebbly, 
  resembling 
  the 
  Orthis-conjinis 
  Sand- 
  

   stones 
  of 
  the 
  Stinchar 
  (Ab 
  1 
  ) 
  in 
  appearance 
  and 
  composition, 
  and 
  

   in 
  the 
  presence 
  of 
  calcareous 
  nodules, 
  as 
  well 
  as 
  in 
  stratigraphical 
  

   position. 
  They 
  contain 
  the 
  usual 
  forms 
  of 
  Orthis, 
  Leptcena, 
  and 
  

   StrqpJiomena, 
  and 
  terminate 
  the 
  visible 
  section. 
  

  

  It 
  is 
  needless 
  to 
  insist 
  upon 
  the 
  fact 
  that 
  we 
  have 
  in 
  this 
  locality 
  

   a 
  section 
  similar 
  in 
  all 
  its 
  details 
  to 
  that 
  typical 
  of 
  the 
  Stinchar 
  

   calcareous 
  series 
  of 
  the 
  district 
  to 
  the 
  south 
  of 
  the 
  Girvan 
  valley, 
  

   the 
  natural 
  members 
  of 
  the 
  succession 
  corresponding 
  precisely 
  in 
  

   both 
  districts 
  in 
  their 
  position 
  in 
  the 
  vertical 
  series 
  and 
  in 
  their 
  

   petrological 
  and 
  palaeontological 
  characters, 
  and 
  differing 
  merely 
  in 
  

   local 
  thickness. 
  

  

  In 
  one 
  grand 
  respect, 
  however, 
  the 
  calcareous 
  rocks 
  of 
  Craig- 
  

   head 
  differ 
  in 
  a 
  most 
  extraordinary 
  degree 
  from 
  their 
  counterparts 
  

   of 
  the 
  Stinchar 
  plateau. 
  In 
  the 
  latter 
  district, 
  these 
  strata, 
  though 
  

   rarely 
  affected 
  by 
  igneous 
  protrusions, 
  are, 
  as 
  a 
  general 
  rule, 
  

   strangely 
  barren 
  of 
  organic 
  remains 
  throughout 
  their 
  entire 
  vertical 
  

   extent. 
  In 
  the 
  present 
  locality, 
  though 
  the 
  beds 
  have 
  been 
  greatly 
  

   shattered 
  and 
  hardened 
  'by 
  faulting 
  and 
  crushing, 
  fossils 
  occur 
  in 
  

   profusion. 
  The 
  indefatigable 
  researches 
  of 
  Mrs. 
  Gray 
  at 
  this 
  locality 
  

   have 
  been 
  rewarded 
  by 
  the 
  discovery 
  of 
  at 
  least 
  100 
  different 
  

   species 
  of 
  fossils 
  of 
  all 
  the 
  chief 
  Lower 
  Palaeozoic 
  groups, 
  affording 
  

   the 
  palaeontologist 
  of 
  the 
  present 
  day 
  a 
  more 
  complete 
  view 
  of 
  the 
  

   fauna 
  of 
  the 
  period 
  than 
  he 
  would 
  be 
  able 
  to 
  construct 
  from 
  all 
  

   the 
  zoological 
  data 
  hitherto 
  collected 
  in 
  Britain 
  bearing 
  upon 
  the 
  

   rocks 
  of 
  Craighead 
  age. 
  

  

  These 
  fossils 
  will 
  be 
  treated 
  of 
  in 
  detail 
  in 
  the 
  second 
  part 
  of 
  the 
  

   present 
  memoir, 
  and 
  it 
  will 
  only 
  be 
  necessary 
  here 
  to 
  make 
  a 
  few 
  

   notes 
  upon 
  the 
  remaining 
  exposures 
  of 
  the 
  calcareous 
  beds 
  seen 
  in 
  

   this 
  locality. 
  

  

  The 
  strata 
  in 
  the 
  new 
  or 
  eastern 
  quarry 
  are 
  folded 
  and 
  faulted 
  

   repetitions 
  of 
  those 
  already 
  described, 
  crushed 
  up 
  against 
  the 
  igneous 
  

   strata 
  of 
  Craighead 
  Hill 
  on 
  the 
  west, 
  and 
  passing 
  out 
  of 
  sight 
  below 
  

   the 
  roadway 
  and 
  clay-covered 
  ground 
  to 
  the 
  east. 
  

  

  2. 
  Calcareous 
  beds 
  of 
  Thunderton 
  and 
  Glenrochie. 
  — 
  The 
  same 
  cal- 
  

   careous 
  series 
  is 
  seen 
  at 
  several 
  points 
  along 
  the 
  Craighead 
  fault, 
  

   both 
  to 
  the 
  south-east 
  and 
  north-east 
  of 
  the 
  quarries 
  themselves 
  ; 
  

   but 
  few 
  of 
  the 
  sections 
  seen 
  are 
  worthy 
  of 
  an 
  extended 
  notice. 
  

   Near 
  the 
  farmhouse 
  of 
  Glenrochrie, 
  a 
  line 
  of 
  deserted 
  quarries 
  affords 
  

  

  