﻿216 
  ACTINOPTERYGII. 
  

  

  small, 
  widely 
  spaced 
  teeth, 
  mostly 
  circular 
  and 
  conspicuously 
  

   mammillated, 
  disposed 
  in 
  from 
  7 
  to 
  10 
  irregular 
  longitudinal 
  

   series, 
  somewhat 
  enlarged 
  towards 
  the 
  symphysial 
  margin 
  of 
  the 
  

   bone. 
  

  

  The 
  dentition 
  of 
  the 
  type 
  specimen 
  measures 
  0-019 
  in 
  maximum 
  

   width 
  and 
  0*045 
  in 
  length. 
  

  

  Form. 
  <$f 
  Log. 
  Lower 
  Portlandian 
  : 
  Boulogne. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Athrodon 
  intermedins, 
  A. 
  S. 
  Woodward. 
  

  

  1893. 
  Athrodon 
  intermedius, 
  A. 
  S. 
  Woodward, 
  Geol. 
  Mag. 
  [3] 
  vol. 
  x. 
  

   p. 
  434, 
  pi. 
  xvi. 
  fig. 
  1. 
  

  

  Type. 
  Left 
  splenial 
  dentition 
  ; 
  British 
  Museum. 
  

  

  Splenial 
  boDe 
  comparatively 
  elongated, 
  with 
  large, 
  closely 
  arranged 
  

   teeth, 
  mostly 
  smooth 
  and 
  nearly 
  circular, 
  a 
  few 
  exhibiting 
  an 
  apical 
  

   pit 
  with 
  feebly 
  crimped 
  margin, 
  disposed 
  in 
  about 
  5 
  or 
  6 
  irregular 
  

   longitudinal 
  series, 
  the 
  largest 
  forming 
  a 
  principal 
  series 
  near 
  the 
  

   symphysial 
  margin 
  of 
  the 
  bone. 
  

  

  Form. 
  Sf 
  Log. 
  Purbeckian 
  : 
  Aylesbury, 
  Buckinghamshire. 
  

  

  40314. 
  The 
  type 
  specimen, 
  described 
  and 
  figured 
  he. 
  cit. 
  The 
  

   dentition 
  measures 
  0*017 
  in 
  maximum 
  width 
  and 
  0*03 
  in 
  

   length. 
  Purchased, 
  1867. 
  

  

  Athrodon 
  crassus, 
  A. 
  S. 
  Woodward. 
  

  

  1893. 
  Athrodon 
  crassus, 
  A. 
  S. 
  Woodward, 
  Geol. 
  Mag. 
  [3] 
  vol. 
  x. 
  p. 
  435, 
  

   pi. 
  xvi. 
  fig. 
  3. 
  

  

  Type. 
  Eight 
  splenial 
  with 
  abraded 
  dentition 
  ; 
  Woodwardian 
  

   Museum, 
  Cambridge. 
  

  

  Splenial 
  bone 
  short 
  and 
  broad, 
  with 
  large, 
  widely-spaced 
  teeth, 
  

   mostly 
  circular, 
  disposed 
  in 
  about 
  four 
  irregular 
  longitudinal 
  series, 
  

   largest 
  near 
  the 
  middle 
  of 
  the 
  bone. 
  

  

  The 
  dentition 
  of 
  the 
  type 
  specimen 
  measures 
  0*02 
  in 
  maximum 
  

   width 
  and 
  0*04 
  in 
  length. 
  

  

  Form. 
  6f 
  Log. 
  Cenomanian 
  : 
  Cambridge. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Athrodon 
  jessoni, 
  A. 
  S. 
  Woodward. 
  

  

  1895. 
  Athrodon 
  jessoni, 
  A. 
  S. 
  Woodward, 
  Geol. 
  Mag. 
  [4] 
  vol. 
  ii. 
  p. 
  208. 
  

   pi. 
  viii. 
  fig. 
  1. 
  

  

  Type. 
  Eight 
  splenial 
  ; 
  British 
  Museum. 
  

  

  Splenial 
  bone 
  very 
  robust, 
  but 
  narrower 
  than 
  in 
  A. 
  crassus, 
  with 
  

  

  