﻿PYCXODONTLD^l. 
  227 
  

  

  following 
  species 
  is 
  named 
  Microdon 
  intermedins, 
  A. 
  Wagner, 
  

   Gelehrte 
  Anzeig. 
  k. 
  bay. 
  Akad, 
  Wiss. 
  vol. 
  1. 
  (1860), 
  p. 
  398. 
  

  

  Form. 
  Sf 
  Log. 
  Lower 
  Kimmeridgian 
  (Lithographic 
  Stone) 
  : 
  Cirin, 
  

   Ain, 
  France. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Microdon 
  itieri 
  (Thiolliere). 
  

  

  1850. 
  Pycnodus 
  itieri, 
  V. 
  Thiolliere, 
  Ann. 
  Soc. 
  Sci. 
  Phys. 
  & 
  Nat. 
  Lyon, 
  

   [2] 
  vol. 
  iii. 
  p. 
  132. 
  

  

  1851. 
  Pycnodus 
  itieri, 
  V. 
  Thiolliere, 
  Poiss. 
  Foss. 
  Bugey, 
  pt. 
  i. 
  p. 
  22, 
  

   with 
  plate 
  and 
  woodcut 
  of 
  dentition, 
  

  

  1856. 
  Microdon 
  itieri, 
  J. 
  J. 
  Heckel, 
  Denkschr. 
  k. 
  Akad. 
  "Wiss., 
  matk.- 
  

  

  naturw. 
  CI. 
  vol. 
  xi. 
  p. 
  201. 
  

   1860. 
  Microdon 
  itieri, 
  A. 
  Wagner, 
  Gelehrte 
  Anzeig. 
  k. 
  bay. 
  Akad. 
  

  

  Wiss. 
  vol. 
  1. 
  p. 
  396. 
  

  

  Type. 
  Nearly 
  complete 
  fish 
  ; 
  Lyons 
  Museum. 
  

  

  A 
  moderately 
  elongated 
  species 
  attaining 
  a 
  length 
  of 
  about 
  0*5. 
  

   Maximum 
  depth 
  of 
  trunk 
  contained 
  three 
  times 
  in 
  the 
  length 
  of 
  the 
  

   head 
  and 
  trunk 
  without 
  caudal 
  fin; 
  head 
  with 
  opercular 
  apparatus 
  

   occupying 
  only 
  about 
  one-fifth 
  of 
  the 
  total 
  length 
  of 
  the 
  fish. 
  Vome- 
  

   rine 
  teeth 
  closely 
  arranged 
  ; 
  those 
  of 
  the 
  median 
  series 
  much 
  broader 
  

   than 
  long 
  ; 
  those 
  of 
  the 
  inner 
  paired 
  series 
  elongated 
  and 
  their 
  

   axis 
  oblique, 
  each 
  pair 
  alternating 
  with 
  the 
  median 
  teeth 
  but 
  

   scarcely 
  pressed 
  between 
  these 
  ; 
  outer 
  teeth 
  irregularly 
  quadrate, 
  

   about 
  as 
  broad 
  as 
  long, 
  and 
  very 
  closely 
  arranged. 
  Splenial 
  teeth 
  

   (according 
  to 
  Thiolliere's 
  diagram) 
  much 
  spaced 
  ; 
  those 
  of 
  the 
  

   principal 
  series 
  two 
  or 
  three 
  times 
  as 
  broad 
  as 
  long, 
  rounded 
  at 
  each 
  

   end 
  ; 
  those 
  of 
  the 
  innermost 
  series 
  minute, 
  and 
  those 
  of 
  the 
  two 
  

   flanking 
  series 
  somewhat 
  broader 
  than 
  long, 
  the 
  outer 
  twice 
  as 
  

   large 
  as 
  those 
  of 
  the 
  inner 
  flanking 
  row. 
  Dorsal 
  fin 
  occupying 
  

   about 
  half 
  of 
  the 
  back, 
  and 
  anal 
  fin 
  more 
  than 
  two-thirds 
  as 
  much 
  

   extended 
  as 
  this. 
  Scales 
  apparently 
  confined 
  to 
  the 
  most 
  anterior 
  

   portion 
  of 
  the 
  trunk. 
  

  

  Form. 
  Sf 
  Log. 
  Lower 
  Kimmeridgian 
  (Lithographic 
  Stone) 
  : 
  Cirin, 
  

   Ain, 
  France. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Microdon 
  hugii 
  (Agassiz). 
  

   [Plate 
  XYII. 
  fig. 
  3.] 
  

  

  1833^4. 
  Pycnodus 
  hugii, 
  L. 
  Agassiz, 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  i. 
  p. 
  17, 
  

  

  pt. 
  ii. 
  p. 
  195, 
  pi. 
  lxxii. 
  a. 
  figs. 
  49-54. 
  

   1846. 
  Pycnodus 
  bucklandi, 
  G. 
  von 
  Minister 
  [errore), 
  Beitr. 
  Petrefakt. 
  

  

  pt. 
  vii. 
  p. 
  40, 
  pi. 
  iii. 
  figs. 
  5 
  a, 
  b. 
  

   1816. 
  Pycnodus 
  preussi, 
  G. 
  von 
  Minister, 
  ibid. 
  p. 
  45, 
  pi. 
  ii. 
  fig. 
  25. 
  

  

  [Splenial 
  ; 
  Palasontological 
  Museum, 
  Munich.] 
  

  

  q2 
  

  

  