﻿Mr. 
  A. 
  S. 
  Woodward's 
  Palmchthyological 
  Notes. 
  301 
  

  

  which 
  are 
  still 
  not 
  capable 
  of 
  separation 
  from 
  the 
  genus 
  Hy- 
  

   bodus 
  ; 
  and 
  the 
  great 
  interest 
  of 
  the 
  tooth 
  consists 
  in 
  the 
  

   remarkable 
  resemblance 
  of 
  its 
  crown 
  to 
  that 
  of 
  the 
  mandibular 
  

   symphysial 
  tooth 
  of 
  some 
  existing 
  forms 
  of 
  Notidanus 
  (e. 
  g. 
  

   N. 
  cinerevs). 
  It 
  is 
  already 
  known 
  that 
  the 
  teeth 
  of 
  the 
  Ju- 
  

   rassic 
  Notidanus 
  can 
  scarcely 
  be 
  distinguished 
  from 
  certain 
  

   types 
  ascribed 
  to 
  Hybodus 
  * 
  ; 
  and 
  whatever 
  may 
  be 
  its 
  pre- 
  

   cise 
  ['generic 
  position, 
  the 
  new 
  fossil 
  just 
  described 
  adds 
  one 
  

   more 
  to 
  the 
  observed 
  points 
  of 
  similarity. 
  

  

  4. 
  On 
  a 
  Maxilla 
  of 
  Saurichthys 
  from 
  the 
  Rhcetic 
  of 
  

   Aust 
  Cliff 
  i 
  near 
  Bristol. 
  

  

  The 
  Eev. 
  G. 
  Hope 
  Dixon, 
  M.A., 
  of 
  Compton 
  Greenfield, 
  

   near 
  Bristol, 
  has 
  kindly 
  favoured 
  the 
  writer 
  with 
  the 
  oppor- 
  

   tunity 
  of 
  studying 
  a 
  unique 
  portion 
  of 
  a 
  fossil 
  jaw 
  from 
  the 
  

   well-known 
  Rhsetic 
  section 
  of 
  Aust 
  Cliff. 
  The 
  specimen 
  is 
  

   well 
  exposed, 
  only 
  one 
  aspect- 
  being 
  hidden 
  by 
  the 
  hard 
  

   matrix; 
  and, 
  as 
  already 
  recognized 
  by 
  Mr. 
  Dixon, 
  the 
  teeth 
  

   exhibited 
  relegate 
  it 
  to 
  the 
  imperfectly 
  known 
  genus 
  and 
  

   species, 
  jSaurichthys 
  acuminatus 
  } 
  Agassiz 
  t- 
  

  

  The 
  fossil 
  is 
  shown 
  of 
  the 
  natural 
  size, 
  from 
  the 
  outer 
  and 
  

   inner 
  aspect 
  respectively, 
  in 
  PI. 
  XIV. 
  figs. 
  7, 
  8 
  ; 
  and 
  a 
  trans- 
  

   verse 
  section 
  at 
  the 
  position 
  of 
  the 
  dotted 
  line 
  in 
  fig. 
  8 
  is 
  

   given 
  in 
  fig. 
  8 
  a. 
  The 
  alveolar 
  border 
  is 
  almost 
  straight 
  ; 
  

   the 
  external 
  face 
  of 
  the 
  bone 
  curves 
  slightly 
  inwards 
  above 
  ; 
  

   and 
  one 
  extremity 
  (presumably 
  the 
  hinder) 
  is 
  considerably 
  

   deeper 
  than 
  the 
  other. 
  The 
  whole 
  of 
  the 
  outer 
  aspect 
  must 
  

   have 
  been 
  originally 
  ornamented 
  with 
  closely 
  and 
  irregularly 
  

   arranged 
  rounded 
  tubercles 
  of 
  ganoine, 
  of 
  which 
  considerable 
  

   tracts 
  are 
  still 
  preserved 
  ; 
  and 
  these 
  tubercles 
  are 
  fewest 
  near 
  

   the 
  superior 
  margin. 
  Externally 
  the 
  alveolar 
  border 
  exhibits 
  

   the 
  bases 
  of 
  a 
  single 
  series 
  of 
  small 
  teeth, 
  somewhat 
  spaced, 
  

   and 
  not 
  precisely 
  uniform 
  in 
  size 
  or 
  arrangement 
  ; 
  and 
  within 
  

   this 
  series 
  are 
  two 
  very 
  large 
  teeth, 
  which 
  evidently 
  repre- 
  

   sent 
  an 
  inner 
  row 
  comprising 
  few 
  teeth 
  at 
  distant 
  intervals. 
  

   In 
  this 
  case 
  there 
  would 
  be 
  about 
  eight 
  outer 
  teeth 
  in 
  the 
  

   space 
  between 
  the 
  positions 
  of 
  the 
  two 
  larger 
  ones. 
  In 
  each 
  

   of 
  the 
  last-named 
  teeth 
  the 
  vertical 
  carina? 
  are 
  anterior 
  and 
  

   posterior, 
  while 
  the 
  outer 
  face 
  is 
  smooth 
  ; 
  and 
  there 
  is 
  a 
  con- 
  

   siderable 
  difference 
  in 
  the 
  proportions 
  of 
  the 
  enamelled 
  apex, 
  

   that 
  of 
  the 
  hinder 
  tooth 
  being 
  relatively 
  the 
  longest 
  and 
  most 
  

   slender. 
  

  

  * 
  Smith 
  Woodward, 
  Geol. 
  Mag. 
  [3] 
  vol. 
  iii. 
  (1886), 
  p. 
  257, 
  pi. 
  vi. 
  

   figs. 
  1, 
  2. 
  

  

  f 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  ii. 
  (1843), 
  p. 
  86, 
  pi. 
  55 
  a. 
  figs. 
  1-5. 
  

  

  