﻿PYCNODONTID^l. 
  

  

  249 
  

  

  Type. 
  Nearly 
  complete 
  fish. 
  

  

  The 
  type 
  species, 
  attaining 
  a 
  length 
  of 
  about 
  0*08. 
  Maximum 
  

   depth 
  of 
  trunk 
  about 
  equal 
  to 
  its 
  length 
  from 
  the 
  scapular 
  arch 
  to 
  

   the 
  base 
  of 
  the 
  caudal 
  fin, 
  and 
  head 
  with 
  opercular 
  apparatus 
  

   occupying 
  somewhat 
  less 
  than 
  one-third 
  of 
  the 
  total 
  length 
  of 
  the 
  

   fish 
  ; 
  arched 
  dorsal 
  contour 
  sharply 
  bent 
  just 
  in 
  advance 
  of 
  the 
  fin. 
  

   External 
  bones 
  closely 
  bat 
  coarsely 
  tuberculated, 
  in 
  part 
  reticulated 
  ; 
  

   all 
  the 
  teeth 
  finely 
  crenulated 
  round 
  the 
  margin 
  of 
  the 
  coronal 
  

   indentation. 
  Dorsal 
  fin 
  comprising 
  about 
  36 
  rays, 
  and 
  its 
  maximum 
  

   elevation 
  not 
  equalling 
  more 
  than 
  one-fourth 
  of 
  the 
  depth 
  of 
  the 
  

   trunk 
  at 
  its 
  insertion 
  ; 
  anal 
  fin 
  with 
  about 
  30 
  rays. 
  Ridge-scales 
  

   finely 
  serrated. 
  

  

  Form. 
  Sf 
  Log. 
  Upper 
  Jurassic 
  : 
  S. 
  Italy. 
  

  

  18600. 
  Slab 
  with 
  two 
  typical 
  specimens; 
  Torre 
  d'Orlando, 
  near 
  

   Naples. 
  Purchased, 
  1844. 
  

  

  23152. 
  Slab 
  with 
  three 
  specimens, 
  in 
  counterpart 
  ; 
  Torre 
  d'Orlando. 
  

  

  Presented 
  by 
  Major 
  Macdonald, 
  1849. 
  

  

  43451. 
  Slab 
  with 
  two 
  specimens, 
  showing 
  part 
  of 
  the 
  dentition 
  ; 
  

   Torre 
  d'Orlando. 
  

  

  Presented 
  by 
  Kenneth 
  Murchison, 
  Esq., 
  1872. 
  

  

  39775. 
  Small 
  fish 
  showing 
  part 
  of 
  the 
  dentition 
  ; 
  Torre 
  d'Orlando. 
  

  

  Purchased, 
  1862. 
  

  

  P. 
  1670-73. 
  Four 
  specimens 
  ; 
  Torre 
  d'Orlando. 
  Egerton 
  Coll. 
  

  

  P. 
  7457. 
  A 
  comparatively 
  elongated 
  fish; 
  Torre 
  d'Orlando. 
  

  

  Genus 
  CCELODUS, 
  Heckel 
  1 
  . 
  

  

  [Denkschr. 
  k. 
  Akad. 
  Wiss., 
  math.-naturw. 
  CI. 
  vol. 
  xi. 
  1856, 
  p. 
  202.] 
  

  

  Syn. 
  Glossodus, 
  O. 
  G. 
  Costa, 
  Atti 
  Aecad. 
  Pontan. 
  vol. 
  vii. 
  1853, 
  p. 
  26. 
  

   Cosmodus, 
  H. 
  E. 
  Sauvage, 
  Bull. 
  Soc. 
  Soi. 
  N*at. 
  Yonne, 
  vol. 
  xxxiii. 
  

   pt. 
  ii. 
  1879, 
  p. 
  48. 
  

  

  Trunk 
  very 
  deeply 
  fusiform, 
  with 
  slender 
  abbreviated 
  caudal 
  

   pedicle. 
  Head 
  and 
  opercular 
  bones 
  externally 
  rugose 
  and 
  punctate 
  ; 
  

   most 
  of 
  the 
  teeth 
  exhibiting 
  an 
  apical 
  indent 
  with 
  crenulated 
  

   border 
  ; 
  oral 
  surface 
  of 
  vomer 
  strongly 
  convex 
  from 
  side 
  to 
  side, 
  

   with 
  teeth 
  in 
  five 
  longitudinal 
  series 
  ; 
  splenial 
  dentition 
  comprising 
  

   three 
  series 
  of 
  teeth 
  with 
  long 
  axes 
  directly 
  transverse, 
  sometimes 
  

  

  1 
  This 
  name 
  having 
  gained 
  universal 
  acceptance, 
  we 
  adopt 
  it, 
  notwithstanding 
  

   its 
  preoccupation 
  among 
  Mammalia 
  by 
  Coelodon, 
  Lund, 
  1839 
  

  

  