﻿562 
  PROF. 
  C. 
  LAPWORTH 
  ON 
  THE 
  GIRVAN 
  SUCCESSION. 
  

  

  the 
  enormous 
  strike-faults 
  which 
  are 
  known 
  to 
  affect 
  the 
  strata 
  

   here, 
  and 
  which 
  finally 
  cut 
  out 
  the 
  limestone 
  hand 
  altogether 
  a 
  few 
  

   yards 
  west 
  of 
  the 
  farmsteading. 
  

  

  5. 
  Oraigbickarae 
  Bill. 
  — 
  Beturning 
  to 
  the 
  opposite 
  side 
  of 
  the 
  

   Stinchar, 
  we 
  resume 
  our 
  description 
  of 
  the 
  unhroken 
  line 
  of 
  the 
  

   Benan 
  and 
  Auchensoul 
  Limestone 
  band 
  at 
  the 
  point 
  where 
  we 
  

   originally 
  commenced. 
  A 
  few 
  yards 
  to 
  the 
  west 
  of 
  our 
  typical 
  sec- 
  

   tion 
  of 
  the 
  Benan 
  Burn 
  we 
  find 
  the 
  calcareous 
  series 
  fairly 
  exposed 
  in 
  

   the 
  cliffs 
  and 
  upper 
  terraces 
  of 
  the 
  projecting 
  mound 
  of 
  Craigbickarae. 
  

   From 
  the 
  steep 
  southern 
  cliff 
  of 
  Craigbickarae 
  itself 
  the 
  purple 
  

   conglomerate 
  looks 
  out 
  in 
  great 
  force 
  over 
  the 
  valley.- 
  In 
  the 
  grass- 
  

   grown 
  terrace 
  above 
  the 
  cliffs 
  the 
  O.-conJinis 
  flags 
  (Ab 
  1 
  ) 
  and 
  their 
  

   more 
  arenaceous 
  associates 
  are 
  buried 
  beneath 
  turf 
  and 
  surface-soil: 
  

   but 
  the 
  overlying 
  purer 
  limestones 
  (Ab 
  £+3 
  ) 
  are 
  shown 
  in 
  several 
  

   small 
  exposures, 
  and, 
  owing 
  to 
  the 
  form 
  of 
  the 
  ground, 
  cover 
  a 
  large 
  

   space 
  upon 
  the 
  hill-side. 
  The 
  beds 
  are 
  much 
  broken 
  by 
  faults 
  and 
  

   slips 
  ; 
  but 
  nevertheless 
  the 
  entire 
  group 
  may 
  be 
  easily 
  followed 
  upon 
  

   the 
  ground 
  from 
  point 
  to 
  point, 
  everywhere 
  emerging 
  in 
  its 
  

   natural 
  order 
  and 
  position 
  from 
  below 
  the 
  great 
  mass 
  of 
  Benan 
  con- 
  

   glomerate 
  (Ac) 
  which 
  forms 
  all 
  the 
  more 
  elevated 
  portions 
  of 
  the 
  hills 
  

   above. 
  The 
  line 
  of 
  contact 
  between 
  the 
  limestone 
  and 
  conglomerate 
  

   is, 
  however, 
  nowhere 
  visible, 
  the 
  Didymo<jraptus-$\iQle$ 
  (Ab 
  4 
  ) 
  being 
  

   cither 
  faulted 
  out 
  or 
  overgrown 
  with 
  grass 
  and 
  vegetation. 
  

  

  In 
  the 
  small 
  burn 
  of 
  Auchlewan 
  the 
  Compact 
  Limestone 
  is 
  fully 
  

   laid 
  open, 
  and 
  in 
  the 
  steep 
  hill-face 
  to 
  the 
  right 
  of 
  it 
  the 
  Orthis- 
  

   conjinis 
  Flagstones 
  &c. 
  are 
  displayed 
  and 
  arc 
  abundantly 
  fossiliferous, 
  

   yielding 
  chiefly 
  Ortliia 
  conjinis, 
  Salt., 
  Stroll 
  tomena, 
  JIaclurea, 
  Tetra- 
  

   dium, 
  sp. 
  

  

  The 
  whole 
  of 
  the 
  calcareous 
  rocks 
  dip 
  steadily 
  into 
  the 
  hill-face 
  to 
  

   the 
  southward, 
  at 
  an 
  angle 
  of 
  about 
  45 
  degrees, 
  and 
  are 
  distinctly 
  

   underlain 
  by 
  masses 
  of 
  the 
  Purple 
  Conglomerate 
  and 
  Sandstone 
  (Aa), 
  

   which 
  are 
  exposed 
  for 
  some 
  distance 
  in 
  the 
  channel 
  of 
  the 
  little 
  burn 
  

   below. 
  

  

  6. 
  Auchlewan. 
  — 
  In 
  an 
  exposure 
  upon 
  the 
  line 
  of 
  junction 
  of 
  the 
  

   Benan 
  Conglomerate 
  and 
  the 
  Calcareous 
  Series, 
  which 
  is 
  apparent 
  

   a 
  few 
  yards 
  to 
  the 
  west 
  of 
  the 
  Auchlewan 
  Burn, 
  some 
  remarkable 
  

   phenomena 
  are 
  observable. 
  In 
  an 
  old 
  quarry 
  above 
  the 
  outer 
  fence 
  

   of 
  the 
  enclosed 
  and 
  formerly 
  cultivated 
  area 
  the 
  line 
  of 
  contact 
  of 
  

   the 
  limestone 
  and 
  conglomerate 
  is 
  plainly 
  visible. 
  The 
  flaggy 
  and 
  

   compact 
  limestones 
  dip 
  into 
  the 
  hill 
  at 
  their 
  normal 
  inclination, 
  and 
  

   are 
  irregularly 
  surmounted 
  by 
  a 
  solid 
  mass 
  of 
  conglomerate 
  dipping 
  

   in 
  the 
  same 
  direction, 
  but 
  at 
  a 
  slightly 
  inferior 
  angle. 
  The 
  line 
  

   of 
  contact 
  is 
  most 
  irregular. 
  The 
  limestone 
  has 
  all 
  the 
  appearance 
  

   of 
  having 
  been 
  greatly 
  eroded 
  previous 
  to 
  the 
  deposition 
  of 
  the 
  

   conglomerate. 
  The 
  regular 
  beds 
  of 
  the 
  limestones 
  strike 
  abruptly 
  

   at 
  the 
  lower 
  portions 
  of 
  the 
  pudding-stone, 
  and 
  patches 
  of 
  the 
  former 
  

   are 
  found 
  adhering 
  irregularly 
  to 
  the 
  weathered 
  basal 
  beds 
  of 
  the 
  

   latter. 
  The 
  conglomerate 
  itself 
  is 
  almost 
  destitute 
  of 
  any 
  thing 
  like 
  

   bedding 
  ; 
  but 
  some 
  of 
  the 
  natural 
  planes 
  of 
  deposition 
  are 
  shown 
  

   by 
  the 
  linear 
  arrangement 
  of 
  bands 
  of 
  small 
  pebbles. 
  In 
  its 
  

  

  