﻿PROF. 
  C. 
  LAPWORTH 
  ON 
  THE 
  GIRVAN 
  SUCCESSION. 
  

  

  615 
  

  

  interpreted 
  ascending 
  succession 
  is 
  displayed 
  in 
  the 
  heights 
  of 
  

   Quarrel 
  Hill, 
  Mulloch 
  Hill, 
  and 
  Glenshalloch. 
  

  

  (a) 
  Sections 
  of 
  the 
  Inner 
  Zones 
  of 
  Strata 
  of 
  the 
  Quarrel-Hill 
  Anticlinal. 
  

   (i) 
  Barren 
  Flagstone-series 
  of 
  Farden 
  and 
  Quarrel 
  Hill. 
  

  

  In 
  the 
  centre 
  of 
  this 
  dome-like 
  area, 
  and 
  consequently 
  occupying 
  

   the 
  lowest 
  horizon 
  in 
  the 
  vertical 
  succession 
  of 
  its 
  rock-formations, 
  

   we 
  find 
  a 
  series 
  of 
  barren 
  flagstones 
  and 
  shales, 
  identical, 
  both 
  in 
  their 
  

   petrological 
  characters 
  and 
  in 
  the 
  few 
  organic 
  remains 
  they 
  yield, 
  

   with 
  our 
  Barren 
  or 
  Shalloch 
  Flagstones 
  of 
  Shalloch 
  and 
  Penwhapple 
  — 
  

   thus 
  presenting, 
  at 
  the 
  very 
  commencement 
  of 
  our 
  study 
  of 
  the 
  rocks 
  

   of 
  this 
  area, 
  a 
  clear 
  and 
  definite 
  horizon 
  of 
  reference 
  for 
  the 
  surround- 
  

   ing 
  and 
  concentric 
  zones 
  of 
  strata 
  of 
  which 
  this 
  northern 
  inlier 
  of 
  

   Lower 
  Palaeozoic 
  rocks 
  is 
  composed. 
  

  

  These 
  flagstones 
  occupy 
  an 
  ellipsoidal 
  area 
  about 
  a 
  mile 
  in 
  length, 
  

   ranging 
  from 
  the 
  loop-fault 
  which 
  bounds 
  the 
  igneous 
  rocks 
  of 
  

   Craighead 
  Hill, 
  through 
  the 
  wooded 
  grounds 
  of 
  Balweary, 
  into 
  the 
  

   grassy 
  slopes 
  of 
  Quarrel 
  Hill. 
  Over 
  much 
  of 
  the 
  area 
  they 
  occupy 
  

   they 
  are 
  hidden 
  from 
  sight 
  by 
  superficial 
  deposits; 
  but 
  excellent 
  

   sections 
  are 
  laid 
  bare 
  in 
  the 
  burns 
  which 
  descend 
  the 
  ridge 
  in 
  the 
  

   direction 
  of 
  Craighead 
  fault, 
  near 
  Kildrummie. 
  The 
  most 
  satisfac- 
  

   tory 
  of 
  these 
  exposures 
  is 
  that 
  seen 
  on 
  the 
  banks 
  of 
  the 
  small 
  stream 
  

   to 
  the 
  west 
  of 
  Quarrel 
  Hill, 
  where 
  the 
  section 
  figured 
  below 
  is 
  dis- 
  

   played 
  from 
  end 
  to 
  end 
  (fig. 
  20). 
  

  

  Fig. 
  20. 
  — 
  Section 
  of 
  the 
  Barren 
  Flagstone 
  Beds 
  of 
  Quarrel 
  Hill. 
  

  

  S.E. 
  

  

  Brachiopoda— 
  Mcristella 
  angustifroiu 
  

  

  t. 
  ' 
  i 
  

  

  .LOC/i 
  H/Ll 
  

  

  J3n:x>-s 
  

  

  x. 
  Carboniferous 
  rocks, 
  not 
  exposed. 
  

   Ca. 
  Mullock-Hill 
  Beds. 
  

  

  2. 
  Calcareous 
  flagstones, 
  with 
  

   Atrypa 
  seotica, 
  &c. 
  

  

  1. 
  Mulloch-Hill 
  conglomerate. 
  

   Bd. 
  Drummuck 
  or 
  Trinacleus-be&s 
  : 
  — 
  

  

  Thin 
  flags 
  and 
  shattered 
  niudstones, 
  with 
  Bellerophon 
  bilobatus 
  &c. 
  

   Be. 
  Barren 
  Flagstones. 
  

  

  (4). 
  Grrey 
  flagstones 
  and 
  shales, 
  weathering 
  buff 
  or 
  yellow. 
  

  

  (3). 
  Green 
  shales 
  and 
  mudstones. 
  

  

  (2). 
  Alternations 
  of 
  thin-bedded 
  green 
  flags 
  and 
  mudstones. 
  

  

  (1). 
  Thin-bedded 
  flaggy 
  beds, 
  with 
  partings 
  of 
  green 
  and 
  grey 
  mudstones- 
  

   Nematolites 
  Grayii 
  and 
  Diplograptus 
  truncatus. 
  

   ff. 
  Faults. 
  

  

  