﻿crick: 
  on 
  glyphioceiias 
  vesicvlifehum. 
  49 
  

  

  satisfactory 
  to 
  be 
  able 
  to 
  state 
  that 
  he 
  considers 
  it 
  highly 
  probable 
  

   that 
  this 
  interpretation 
  is 
  correct. 
  

  

  The 
  condition 
  of 
  Dr. 
  Hind's 
  fossil 
  already 
  mentioned 
  explains 
  the 
  

   chief 
  difference 
  between 
  the 
  suture-line 
  figured 
  by 
  him 
  and 
  that 
  

   figured 
  and 
  described 
  by 
  De 
  IConinck, 
  for 
  whilst 
  De 
  Koninck 
  has 
  

   described 
  and 
  figured 
  tliat 
  portion 
  of 
  tbe 
  septal 
  suture 
  whicli 
  is 
  

   usually 
  figured 
  and 
  described, 
  viz., 
  tbe 
  portion 
  extending 
  from 
  tbe 
  

   umbilicus 
  on 
  one 
  side 
  over 
  the 
  ])eripliery 
  (or 
  venter) 
  to 
  the 
  umbilicus 
  

   on 
  the 
  other 
  side, 
  that 
  is 
  to 
  say, 
  its 
  lateral 
  and 
  ventral 
  portions, 
  

   Dr. 
  Hind 
  bas 
  figured 
  the 
  edge 
  of 
  tbe 
  septum 
  as 
  it 
  appears 
  on 
  the 
  inside 
  

   of 
  tlie 
  dorsal 
  (inner) 
  portion 
  of 
  the 
  outer 
  whorl, 
  wlieu 
  tbe 
  floor 
  of 
  this 
  

   whorl 
  remains 
  attached 
  to 
  the 
  penultimate 
  whorl 
  on 
  the 
  removal 
  of 
  

   tbe 
  outer 
  whorl 
  itself 
  ; 
  that 
  is 
  to 
  say, 
  he 
  bas 
  figured 
  the 
  dorsal 
  

   portion 
  of 
  tbe 
  septal 
  suture' 
  (see 
  Fig. 
  1, 
  D). 
  Portions, 
  however, 
  of 
  

   tbe 
  peripheral 
  and 
  lateral 
  parts 
  of 
  the 
  septal 
  sutures 
  are 
  visible 
  near 
  

   tlie 
  anterior 
  end 
  of 
  the 
  specimen 
  on 
  the 
  natural 
  internal 
  cast.* 
  They 
  

   are 
  indicated 
  in 
  the 
  accompanying 
  figure 
  (Fig. 
  1, 
  A). 
  Unfortunately 
  

   some 
  of 
  the 
  peripheral 
  surface 
  of 
  tbe 
  specimen 
  bas 
  here 
  been 
  ground 
  

   away, 
  so 
  that 
  the 
  course 
  of 
  the 
  septal 
  suture 
  cannot 
  be 
  traced 
  over 
  tbe 
  

   periplieral 
  portion 
  of 
  the 
  natural 
  internal 
  cast, 
  but 
  this 
  portion 
  of 
  

   tiie 
  septal 
  suture 
  can 
  be 
  seen 
  at 
  a 
  point 
  a 
  little 
  further 
  back 
  (where 
  

   the 
  sbell 
  lias 
  a 
  diameter 
  of 
  18'4 
  mm.) 
  on 
  tbe 
  median 
  portion 
  of 
  tbe 
  

   periphery, 
  and 
  is 
  shown 
  in 
  the 
  accompanying 
  figure 
  (Fig. 
  1, 
  \\). 
  The 
  

   septal 
  suture, 
  so 
  far 
  as 
  it 
  can 
  be 
  made 
  out, 
  is 
  reproduced 
  in 
  the 
  

   accompanying 
  figures 
  (Fig. 
  1, 
  A-D). 
  

  

  The 
  measurements 
  of 
  Dr. 
  Hind's 
  specimen 
  are: 
  Diameter 
  of 
  

   shell, 
  22'5 
  mm. 
  (100) 
  ; 
  thickness 
  of 
  wborl, 
  12'5mm. 
  (55"5) 
  ; 
  height 
  of 
  

   whorl, 
  ir5 
  mm. 
  (51) 
  ; 
  ditto 
  above 
  preceding 
  wborl, 
  7"0 
  mm. 
  (STl) 
  ; 
  

   Avidth 
  of 
  umbilicus, 
  3"0 
  mm. 
  (13"3). 
  Tiie 
  corresponding 
  measure- 
  

   ments 
  of 
  De 
  Koninck's 
  specimen 
  as 
  taken 
  from 
  his 
  figure 
  are 
  : 
  

   Diameter 
  of 
  sbtdl, 
  19 
  mm. 
  (lOO); 
  thickness 
  of 
  whorl, 
  10'5 
  mm. 
  

   (55'2) 
  ; 
  height 
  of 
  wborl, 
  10 
  mm. 
  (52"6) 
  ; 
  ditto 
  above 
  preceding 
  whorl, 
  

   5-25 
  mm. 
  (27"5) 
  ; 
  widtb 
  of 
  umbilicus, 
  3"0 
  mm. 
  (15"7). 
  It 
  will 
  thus 
  

   be 
  seen 
  that 
  the 
  relative 
  dimen.sions 
  of 
  tbe 
  two 
  specimens 
  agree 
  

   fairly 
  well. 
  

  

  Notwithstanding 
  tbe 
  differences, 
  tberefore, 
  which 
  are 
  apparent 
  

   between 
  De 
  Koninck's 
  description 
  and 
  that 
  of 
  Dr. 
  Hind, 
  we 
  think 
  

   these 
  can 
  be 
  satisfactorily 
  explained, 
  and 
  that 
  the 
  English 
  fossil 
  is 
  

   certainly 
  very 
  near 
  to, 
  and 
  probably 
  iilentical 
  with, 
  De 
  Koninck's 
  

   species. 
  

  

  Tbe 
  borizon 
  and 
  localities 
  of 
  this 
  species 
  given 
  by 
  De 
  Koninck 
  

   are 
  the 
  Carboniferous 
  Limestone 
  of 
  Vise, 
  Belgium 
  (assise 
  vi), 
  and 
  

   tbe 
  Carboniferous 
  Limestone 
  of 
  Settle, 
  Yorksbiie. 
  The 
  specimen 
  

   described 
  and 
  figured 
  by 
  Dr. 
  Hind 
  was 
  from 
  the 
  Carboniferous 
  Lime- 
  

   stone 
  of 
  Elbolton, 
  near 
  Cracoe, 
  Yorkshire 
  (Upper 
  Dibunophyllum 
  

  

  ' 
  The 
  broad 
  curve 
  on 
  the 
  lateral 
  area 
  of 
  the 
  whorl 
  figured 
  as 
  part 
  of 
  the 
  septal 
  

   suture 
  is 
  also 
  described 
  by 
  Dr. 
  Hind 
  as 
  part 
  of 
  tlie 
  ornament 
  of 
  the 
  shell. 
  

  

  - 
  These 
  are 
  indicated 
  in 
  Dr. 
  Hind's 
  lig. 
  2 
  by 
  the 
  curved 
  hnes 
  close 
  to 
  the 
  

   anterior 
  end 
  and 
  in 
  front 
  of 
  the 
  longitudinal 
  vesicular 
  ridges. 
  

  

  VOL. 
  XII. 
  — 
  M.\RCH, 
  1916. 
  4 
  

  

  