﻿PYCNODONTID^. 
  

  

  229 
  

  

  P. 
  1650, 
  P. 
  3748. 
  Right 
  and 
  left 
  splenial 
  dentition, 
  of 
  small 
  size 
  ; 
  

   Corallian, 
  Lindnerberg, 
  Hanover. 
  

  

  Egerton 
  and 
  Enniskillen 
  Colls. 
  

  

  30871. 
  Left 
  splenial 
  dentition, 
  probably 
  of 
  this 
  species, 
  shown 
  of 
  

   the 
  natural 
  size 
  in 
  PI. 
  XYII. 
  fig. 
  3 
  ; 
  Portland 
  Stone, 
  

   Weymouth. 
  Purchased, 
  1856. 
  

  

  Microdon 
  minutus 
  (Miinster). 
  

  

  1846. 
  Pycnodus 
  minutus, 
  G. 
  von 
  Minister, 
  Beitr. 
  Petrefakt. 
  pt. 
  vii. 
  

  

  p. 
  41, 
  pi. 
  hi. 
  fig. 
  7. 
  

   1875. 
  Microdon 
  minutus, 
  K. 
  Fricke, 
  Paleeontogr. 
  vol. 
  xxii. 
  p. 
  369, 
  pi. 
  xx. 
  

  

  figs. 
  5-9. 
  

  

  Type. 
  Fragment 
  of 
  mandibular 
  dentition 
  ; 
  Paheontological 
  

   Museum, 
  Munich. 
  

  

  A 
  species 
  of 
  moderate 
  size, 
  known 
  only 
  by 
  the 
  dentition. 
  On 
  the 
  

   vomer 
  [according 
  to 
  Fricke] 
  the 
  teeth 
  of 
  the 
  principal 
  series 
  much 
  

   transversely 
  elongated, 
  comparatively 
  closely 
  arranged; 
  those 
  of 
  

   the 
  inner 
  paired 
  series 
  minute 
  or 
  aborted 
  ; 
  those 
  of 
  the 
  outer 
  paired 
  

   series 
  small 
  and 
  irregularly 
  rounded. 
  Splenial 
  teeth 
  closely 
  arranged 
  ; 
  

   those 
  of 
  the 
  principal 
  series 
  at 
  least 
  twice 
  as 
  broad 
  as 
  long 
  : 
  those 
  

   of 
  the 
  innermost 
  series 
  round 
  and 
  minute 
  ; 
  those 
  of 
  the 
  inner 
  

   flanking 
  series 
  much 
  transversely 
  elongated, 
  relatively 
  large, 
  and 
  

   those 
  of 
  the 
  outer 
  flanking 
  series 
  smaller, 
  either 
  round 
  or 
  slightly 
  

   elongated 
  transversely. 
  

  

  Form. 
  § 
  Log. 
  Kimmeridgian 
  : 
  Hanover 
  ; 
  Switzerland. 
  

  

  P. 
  3747. 
  Left 
  splenial 
  dentition 
  ; 
  Lindnerberg, 
  Hanover. 
  

  

  Enniskillen 
  Coll. 
  

  

  P. 
  3746 
  a. 
  Portion 
  of 
  larger 
  right 
  splenial 
  dentition 
  ; 
  Soleure, 
  

   Switzerland. 
  Enniskillen 
  Coll. 
  

  

  Microdon 
  quincuncialis 
  (Blake). 
  

  

  1875. 
  Pycnodus 
  quincuncialis, 
  J. 
  F. 
  Blake, 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  

  

  vol. 
  xxxi. 
  p. 
  223. 
  

   1880. 
  Pycnodus 
  quincuncialis, 
  R. 
  Damon, 
  Geol. 
  Weymouth, 
  ed. 
  2, 
  

  

  Suppl. 
  pi. 
  xi. 
  fig. 
  10. 
  

   1890. 
  Microdon 
  quincuncialis, 
  Woodward 
  & 
  Sherborn, 
  Catal. 
  Brit. 
  

  

  Foss. 
  Vertebrata, 
  p. 
  122. 
  

  

  Type. 
  Vomerine 
  dentition 
  ; 
  British 
  Museum. 
  

  

  A 
  species 
  of 
  large 
  size. 
  Inner 
  vomerine 
  teeth 
  sparsely 
  arranged, 
  

   those 
  of 
  the 
  principal 
  series 
  not 
  much 
  broader 
  than 
  long, 
  and 
  the 
  

   paired 
  teeth 
  very 
  irregular 
  in 
  size 
  and 
  form, 
  with 
  few 
  supplementary 
  

  

  