﻿656 
  

  

  PEOF. 
  C. 
  LAPWOETH 
  ON 
  THE 
  GIEVAN 
  SUCCESSION. 
  

  

  of 
  the 
  farm-house 
  of 
  Craig, 
  fine 
  greenish-grey 
  shales 
  are 
  exposed, 
  not 
  

   unlike 
  those 
  of 
  the 
  quarries 
  east 
  of 
  Blackwood 
  Head 
  ; 
  but 
  the 
  latter 
  

   lie 
  at 
  the 
  northern 
  limits 
  of 
  the 
  Blackwood 
  beds, 
  while 
  these 
  Craig 
  

   shales, 
  if 
  the 
  strike 
  of 
  the 
  beds 
  is 
  to 
  be 
  trusted, 
  lie 
  on 
  the 
  oppo- 
  

   site 
  or 
  southern 
  side 
  of 
  the 
  band. 
  

  

  No 
  further 
  exposure 
  of 
  any 
  moment 
  is 
  seen 
  in 
  this 
  direction 
  till 
  

   we 
  cross 
  the 
  supposed 
  line 
  of 
  the 
  Braehill 
  fault 
  on 
  the 
  Bargany 
  Hill, 
  

   and 
  enter 
  upon 
  the 
  Straiton 
  band 
  of 
  Silurian 
  strata, 
  which, 
  near 
  

   Blair 
  Farm, 
  emerges 
  from 
  below 
  the 
  Carboniferous 
  rocks 
  of 
  that 
  

   district. 
  

  

  3. 
  Blair 
  Farm 
  and 
  Drwmyork. 
  — 
  The 
  Silurian 
  strata 
  are 
  laid 
  open 
  

   in 
  many 
  sections 
  in 
  the 
  course 
  of 
  the 
  Lady 
  Burn 
  above 
  Kilkerran 
  

   House, 
  near 
  Drumyork, 
  and 
  in 
  the 
  grassy 
  mounds 
  around 
  the 
  farm- 
  

   house 
  of 
  Blair. 
  The 
  disposition 
  of 
  the 
  strata 
  at 
  this 
  locality 
  will 
  be 
  

   evident 
  on 
  a 
  study 
  of 
  the 
  accompanying 
  section 
  (fig. 
  29). 
  

  

  Fig. 
  29. 
  — 
  Section 
  of 
  the 
  Grey 
  Flags 
  and 
  Shales 
  of 
  Blair 
  and 
  

   Drumyork. 
  

  

  N.W. 
  

  

  Srcun-yarA 
  flags 
  

  

  Jlcu-r 
  £A 
  aJca 
  tLsttLTta 
  

  

  

  D. 
  Dailly 
  Series. 
  

  

  Db. 
  Straiton 
  beds. 
  

  

  (6) 
  Blair 
  shales 
  and 
  flags, 
  with 
  Cardiola, 
  Ceratiocaris, 
  Retiolitcs, 
  

  

  and 
  Monoyraptus 
  vomerinus. 
  

   (a) 
  Drumyork 
  flags, 
  olive-green, 
  non-fossiliferous. 
  

  

  What 
  are 
  considered 
  to 
  be 
  the 
  lowest 
  beds 
  are 
  seen 
  in 
  the 
  stream- 
  

   course 
  close 
  to 
  the 
  Bargany 
  fault 
  above 
  Drumyork. 
  They 
  

   consist 
  of 
  olive-green 
  flags 
  and 
  shales, 
  much 
  jointed 
  and 
  con- 
  

   torted, 
  crushed 
  abruptly 
  against 
  the 
  Old 
  Red 
  Sandstone 
  rocks 
  to 
  the 
  

   south. 
  

  

  These 
  beds 
  are 
  succeeded 
  by 
  flaggy 
  shales 
  with 
  occasional 
  ribs 
  of 
  

   flagstone, 
  weathering 
  often 
  of 
  a 
  dull 
  yellowish 
  tint, 
  some 
  striped 
  

   with 
  lines 
  of 
  carbonaceous 
  shales, 
  others 
  of 
  a 
  cold 
  olive-green 
  colour, 
  

   more 
  or 
  less 
  calcareous, 
  and 
  with 
  rough 
  harsh 
  flaky 
  surface. 
  These 
  

   are 
  exhibited 
  in 
  many 
  natural 
  and 
  artificial 
  openings 
  on 
  the 
  south 
  

   side 
  of 
  the 
  hill-road 
  between 
  Drumyork 
  and 
  Blair 
  Farm. 
  In 
  a 
  quarry 
  

   about 
  a 
  hundred 
  yards 
  east 
  of 
  the 
  farmsteading 
  they 
  afford 
  in 
  great 
  

   abundance 
  the 
  characteristic 
  fossil 
  Monograptus 
  vomerinus, 
  Nich., 
  

   and 
  less 
  commonly 
  the 
  following 
  species 
  : 
  — 
  

  

  Beyrichia 
  Kloedeni, 
  M'Coy. 
  

   Orthoceras 
  subundnlatum, 
  Portl. 
  

   Eetiolites 
  Geinitzianus, 
  Barr. 
  

  

  Cardiola 
  fibrosa, 
  Sow. 
  

   Bellerophon 
  wenlockensis, 
  Sow. 
  

   Cyrtograptus, 
  sp. 
  

  

  

  