﻿^°1' 
  53-1 
  PETALOGBAPTUS 
  AND 
  CEPHALOGBAPTT/S. 
  211 
  

  

  Figs. 
  10-16. 
  Cephalograptus 
  cometa 
  (G-ein.). 
  

  

  Fig. 
  *10. 
  Obverse 
  aspect 
  of 
  an 
  incomplete 
  specimen. 
  Duffkinnell 
  Burn. 
  

  

  11. 
  Obverse 
  aspect 
  of 
  a 
  curved 
  specimen 
  ; 
  proximal 
  end 
  wanting. 
  

  

  Belcraig 
  Burn. 
  

  

  12. 
  Obverse 
  aspect 
  of 
  a 
  complete 
  specimen, 
  showing 
  the 
  position 
  of 
  the 
  

  

  sicula. 
  Kongslena. 
  

  

  13. 
  Distal 
  end, 
  preserved 
  in 
  relief, 
  showing 
  characteristic 
  thecal 
  

  

  striations. 
  Tommarp. 
  

  

  14. 
  Reverse 
  aspect 
  of 
  proximal 
  end, 
  showing 
  position 
  of 
  the 
  sicula 
  and 
  

  

  course 
  of 
  the 
  virgula. 
  Preserved 
  in 
  relief. 
  Tommarp. 
  

  

  15. 
  Obverse 
  aspect 
  of 
  proximal 
  end 
  ; 
  preserved 
  in 
  relief. 
  Tommarp. 
  

  

  16. 
  Obverse 
  aspect 
  of 
  proximal 
  end 
  of 
  a 
  curved 
  specimen 
  ; 
  preserved 
  in 
  

  

  relief. 
  Tommarp. 
  

  

  Plate 
  XI 
  V. 
  

  

  Figs. 
  1-4. 
  Petalograptus 
  palwzeus, 
  sensu 
  stricto 
  (Barr.). 
  

  

  Fig. 
  *1. 
  Reverse 
  aspect 
  of 
  a 
  mature 
  specimen, 
  showing 
  the 
  sicula 
  with 
  the 
  

   apertural 
  spine. 
  Owing 
  to 
  the 
  mode 
  of 
  preservation, 
  the 
  sicula 
  is 
  

   seen 
  through 
  from 
  the 
  obverse 
  side. 
  Zelkovice. 
  

  

  2. 
  Obverse 
  aspect 
  of 
  mature 
  specimen, 
  showing 
  the 
  sicula 
  and 
  the 
  

  

  general 
  characters 
  of 
  the 
  proximal 
  end. 
  Conway. 
  

  

  3. 
  Obverse 
  aspect, 
  showing 
  the 
  splitting 
  of 
  the 
  virgula 
  within 
  the 
  

  

  rhabdosoma. 
  Dobb's 
  Linn. 
  

  

  *4. 
  Obverse 
  aspect 
  of 
  wide 
  specimen. 
  Zelkovice. 
  

  

  Figs. 
  5-8. 
  P. 
  palmeus, 
  var. 
  latus 
  (Barr.). 
  

  

  Fig. 
  *5. 
  Obverse 
  aspect, 
  showing 
  the 
  characters 
  of 
  the 
  proximal 
  end. 
  

  

  Frenchland 
  Burn. 
  

  

  6. 
  Reverse 
  aspect 
  of 
  a 
  young 
  specimen 
  ; 
  base 
  of 
  sicula 
  seen 
  on 
  the 
  left. 
  

  

  Dobb's 
  Linn. 
  

  

  7. 
  Obverse 
  aspect 
  of 
  mature 
  specimen, 
  showing 
  the 
  sicula 
  with 
  the 
  

  

  apertural 
  spine. 
  Preserved 
  in 
  half 
  relief. 
  Tommarp. 
  

  

  8. 
  Transverse 
  section 
  through 
  the 
  middle 
  of 
  a 
  mature 
  specimen, 
  showing 
  

  

  the 
  septum 
  and 
  the 
  position 
  of 
  the 
  virgula. 
  Specimen 
  preserved 
  

   in 
  iron 
  pyrites. 
  Skelgill. 
  

  

  Figs. 
  9, 
  10. 
  P. 
  palmeus, 
  var. 
  tenuis 
  (Barr.). 
  

  

  Fig. 
  9. 
  Obverse 
  aspect 
  of 
  mature 
  specimen, 
  showing 
  the 
  sicula 
  with 
  the 
  

  

  apertural 
  spine. 
  Skelgill. 
  

  

  10. 
  Obverse 
  aspect, 
  in 
  relief, 
  of 
  a 
  young 
  specimen, 
  showing 
  the 
  sicula, 
  

  

  the 
  general 
  characters 
  of 
  the 
  proximal 
  end, 
  and 
  the 
  growth-lines 
  

  

  on 
  the 
  thecae. 
  Dobb's 
  Linn. 
  

  

  Figs. 
  11-14. 
  P. 
  palmeus, 
  var. 
  ovato-elongatus 
  (Kurck). 
  

  

  Fig. 
  11. 
  Reverse 
  aspect 
  of 
  a 
  mature 
  specimen, 
  with 
  the 
  apertural 
  spine. 
  The 
  

   cells 
  on 
  the 
  right 
  side 
  have 
  been 
  affected 
  by 
  pressure. 
  

  

  Dobb's 
  Linn. 
  

  

  12. 
  Obverse 
  aspect, 
  in 
  relief, 
  of 
  a 
  young 
  specimen 
  not 
  complete. 
  Skelgill. 
  

  

  13. 
  Obverse 
  aspect, 
  in 
  relief, 
  of 
  a 
  mature 
  specimen. 
  Skelgill. 
  

  

  14. 
  Transverse 
  section 
  of 
  a 
  specimen, 
  preserved 
  in 
  relief, 
  showing 
  the 
  

  

  continuous 
  septum 
  and 
  the 
  position 
  of 
  the 
  virgula. 
  Skelgill. 
  

  

  Figs. 
  15, 
  16. 
  Petalograptus 
  ovatus 
  (Barr.). 
  

  

  Fig. 
  *15. 
  Reverse 
  aspect, 
  showing 
  the 
  sicula 
  through 
  from 
  the 
  obverse 
  side 
  ; 
  

   typical 
  form 
  showing 
  alteration 
  in 
  the 
  angle 
  of 
  inclination. 
  

  

  Zelkovice. 
  

  

  *16. 
  Reverse 
  aspect 
  of 
  a 
  more 
  oval 
  form, 
  showing 
  alteration 
  in 
  the 
  angle 
  

  

  of 
  inclination. 
  Zelkovice. 
  

  

  