﻿Mr. 
  A. 
  S. 
  Woodward's 
  P 
  alee 
  ichthyolog 
  iced 
  Notes. 
  297 
  

  

  XXXll.—Palceichthyological 
  Notes. 
  By 
  A. 
  Smith 
  Wood- 
  

   ward, 
  F.G.S., 
  F.Z.S., 
  of 
  the 
  British 
  Museum 
  (Natural 
  

   History). 
  

  

  [Plate 
  XIV.] 
  

  

  1. 
  On 
  the 
  so-called 
  Hybodus 
  keuperinus, 
  Murch. 
  & 
  

   Strickl. 
  

  

  Detached 
  Selachian 
  teeth 
  of 
  a 
  Hybodont 
  or 
  Cestraciont 
  

   type 
  have 
  long 
  been 
  known 
  from 
  the 
  Keuper 
  of 
  the 
  Midlands, 
  

   and 
  one 
  was 
  figured 
  so 
  early 
  as 
  1840 
  by 
  Murch 
  ison 
  and 
  

   Strickland, 
  who 
  recorded 
  it 
  under 
  the 
  generic 
  name 
  of 
  Hy- 
  

   bodus 
  *. 
  Several 
  of 
  these 
  teeth 
  have 
  now 
  been 
  discovered 
  in 
  

   natural 
  association 
  in 
  the 
  Upper 
  Keuper 
  Sandstone 
  of 
  

   Shrewley, 
  Warwickshire, 
  by 
  the 
  Rev. 
  P. 
  B. 
  Brodie, 
  M.A., 
  

   F.G.S., 
  who 
  has 
  kindly 
  entrusted 
  them 
  to 
  the 
  present 
  writer 
  

   for 
  study 
  ; 
  and 
  the 
  following 
  brief 
  notes 
  are 
  suggested 
  by 
  an 
  

   examination 
  of 
  the 
  interesting 
  new 
  specimens. 
  

  

  Only 
  four 
  disconnected 
  fragments 
  of 
  the 
  dentition 
  are 
  

   preserved 
  ; 
  but 
  the 
  general 
  arrangement 
  of 
  the 
  teeth 
  is 
  well 
  

   shown 
  and 
  the 
  finest 
  example 
  is 
  figured 
  of 
  the 
  natural 
  size 
  in 
  

   PI. 
  XIV. 
  fig. 
  1. 
  Here 
  are 
  exhibited 
  portions 
  of 
  three 
  trans- 
  

   verse 
  series 
  of 
  teeth, 
  disposed 
  as 
  in 
  ordinary 
  Cestracionts, 
  

   the 
  largest 
  series 
  measuring 
  001 
  in 
  width 
  and 
  comprising 
  

   six 
  teeth, 
  the 
  next 
  much 
  smaller, 
  measuring 
  0*008 
  in 
  width 
  

   and 
  showing 
  five 
  teeth, 
  and 
  the 
  third 
  series 
  still 
  smaller 
  and 
  

   too 
  imperfect 
  for 
  description. 
  In 
  one 
  of 
  the 
  more 
  fragmentary 
  

   specimens 
  (PI. 
  XIV. 
  fig. 
  2) 
  , 
  a 
  series 
  corresponding 
  in 
  size 
  

   and 
  characters 
  to 
  the 
  second 
  of 
  PI. 
  XIV. 
  fig. 
  1 
  exhibits 
  

   traces 
  of 
  not 
  less 
  than 
  eight 
  teeth 
  ; 
  and 
  immediately 
  adjoining 
  

   this 
  on 
  one 
  side 
  are 
  a 
  few 
  teeth 
  similar 
  to 
  the 
  largest 
  in 
  the 
  

   first 
  group, 
  while 
  on 
  the 
  opposite 
  side 
  are 
  the 
  bases 
  of 
  the 
  

   teeth 
  of 
  a 
  smaller 
  series 
  0*005 
  in 
  width. 
  The 
  crown 
  in 
  all 
  

   the 
  teeth 
  is 
  much 
  compressed 
  at 
  right 
  angles 
  to 
  the 
  long- 
  

   axis, 
  forming 
  a 
  sharp 
  longitudinal 
  keel 
  ; 
  and 
  the 
  outer 
  face 
  

   is 
  deeper 
  than 
  the 
  inner 
  face, 
  the 
  coronal 
  apex 
  being 
  thus 
  

   inclined 
  inwards 
  and 
  overlapping 
  to 
  some 
  extent 
  the 
  outer 
  

   margin 
  of 
  the 
  tooth 
  within. 
  Broken 
  teeth 
  also 
  show 
  a 
  large 
  

   internal 
  cavity 
  (PI. 
  XIV. 
  fig. 
  2). 
  

  

  The 
  coronal 
  surface 
  in 
  all 
  the 
  teeth 
  is 
  marked 
  by 
  large 
  

   transverse 
  wrinkles, 
  which 
  are 
  broadest 
  or 
  bifurcated 
  at 
  the 
  

   outer 
  and 
  inner 
  margins 
  and 
  attenuated 
  towards 
  the 
  central 
  

  

  * 
  Trans. 
  Geol. 
  Soc. 
  [2] 
  vol. 
  v. 
  (1840), 
  pi. 
  xxviii. 
  fig. 
  3*. 
  

  

  