﻿230 
  ACTINOPTERYGII. 
  

  

  minute 
  teeth 
  ; 
  teeth 
  of 
  the 
  outer 
  paired 
  series 
  closely 
  arranged, 
  

   longer 
  than 
  broad, 
  and 
  truncated 
  externally. 
  

   Form. 
  Sf 
  Loc. 
  Kimmeridgian 
  : 
  Dorsetshire. 
  

  

  P. 
  6170. 
  Type 
  specimen; 
  Lower 
  Kimmeridge 
  Clay, 
  Weymouth. 
  

  

  Damon 
  Coll. 
  

  

  P. 
  6749. 
  Imperfect 
  right 
  splenial 
  dentition 
  probably 
  of 
  this 
  species, 
  

   though 
  possibly 
  an 
  abnormal 
  example 
  of 
  Gyrodus 
  cocco- 
  

   derma, 
  exhibiting 
  the 
  principal 
  teeth 
  of 
  a 
  very 
  irregular 
  

   form, 
  scarcely 
  broader 
  than 
  long, 
  and 
  the 
  inner 
  flanking 
  

   series 
  slightly 
  larger 
  than 
  the 
  outer 
  series 
  ; 
  Weymouth. 
  

  

  Purchased, 
  1892. 
  

  

  47965. 
  Larger 
  imperfect 
  specimen 
  of 
  the 
  same 
  form 
  of 
  splenial 
  

   dentition 
  ; 
  Coral 
  Rag, 
  Wheatley. 
  

  

  Presented 
  by 
  the 
  Hon. 
  Robert 
  Mar 
  sham, 
  1877. 
  

  

  Microdon 
  pagoda 
  (Blake). 
  

  

  1880. 
  Pycnodus 
  pagoda, 
  J. 
  F. 
  Blake, 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xxxvi. 
  

   p. 
  228, 
  pi. 
  x. 
  fig. 
  10. 
  

  

  1889. 
  Microdon 
  payoda, 
  A. 
  S. 
  Woodward, 
  Geol. 
  Mag. 
  [3] 
  vol. 
  vi. 
  p. 
  454. 
  

  

  Type. 
  Vomerine 
  dentition. 
  

  

  A 
  species 
  of 
  small 
  or 
  moderate 
  size, 
  known 
  only 
  by 
  the 
  vomerine 
  

   dentition, 
  which 
  is 
  somewhat 
  arched 
  from 
  side 
  to 
  side. 
  Teeth 
  of 
  

   the 
  median 
  or 
  principal 
  series 
  at 
  least 
  twice 
  as 
  broad 
  as 
  long 
  ; 
  those 
  

   of 
  the 
  inner 
  pair 
  about 
  half 
  as 
  large 
  as 
  the 
  latter, 
  with 
  tendency 
  

   to 
  oblique 
  elongation 
  ; 
  those 
  of 
  the 
  outer 
  paired 
  series 
  much 
  

   smaller, 
  irregular 
  in 
  shape 
  and 
  size, 
  and 
  not 
  much 
  truncated 
  ex- 
  

   ternally. 
  

  

  Form. 
  Sf 
  Loc, 
  Portlandian 
  : 
  Dorsetshire. 
  

  

  40640 
  a. 
  Vomerine 
  dentition 
  ; 
  Portland 
  Stone, 
  near 
  Weymouth. 
  

  

  Purchased, 
  1867. 
  

  

  P. 
  4678. 
  Smaller 
  specimen 
  ; 
  Bidgway 
  Quarry, 
  near 
  Weymouth. 
  

  

  Presented 
  by 
  C. 
  Westendarp, 
  Esq., 
  1884. 
  

  

  P. 
  7187. 
  Another 
  small 
  vomer 
  ; 
  near 
  Weymouth. 
  Purchased, 
  1894. 
  

  

  Microdon 
  biserialis, 
  A. 
  S. 
  Woodward. 
  

  

  1844. 
  Pycnodus 
  biserialis, 
  L. 
  Agassiz, 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  ii. 
  p. 
  199 
  

   (name 
  only). 
  

  

  1890. 
  Mesodon 
  biserialis, 
  A. 
  S. 
  Woodward, 
  Proc. 
  Geol. 
  Assoc, 
  vol. 
  xi. 
  

   p. 
  300 
  ; 
  pi. 
  iii. 
  fig. 
  28. 
  

  

  Type. 
  Left 
  splenial 
  dentition 
  British 
  Museum. 
  

  

  