﻿248 
  ACTINOPTERYGII. 
  

  

  Oyrodus 
  navicularis, 
  T. 
  C. 
  Winkler, 
  Archiv. 
  Musee 
  Teyler, 
  

   vol. 
  iv. 
  (1874), 
  p. 
  30, 
  pi. 
  ii. 
  figs. 
  19-21.— 
  Middle 
  Eocene 
  

   (Bruxellian) 
  ; 
  Uccle, 
  Brussels. 
  [Not 
  Pycnodont.] 
  

  

  Gyrodus 
  quadratus, 
  A. 
  E. 
  Reuss, 
  Yerstein. 
  bohm. 
  Kreideform. 
  

   pt. 
  i. 
  (1845), 
  p. 
  9, 
  pi. 
  iv. 
  figs. 
  56-61. 
  — 
  Cenomanian 
  ; 
  

   Bohemia. 
  

  

  Gyrodus 
  rugulosus, 
  L. 
  Agassiz, 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  ii. 
  (1844), 
  

   p. 
  235, 
  pi. 
  lxix. 
  a. 
  fig. 
  16. 
  — 
  Cenomanian 
  ; 
  Regensburg, 
  

   Bavaria. 
  [Royal 
  Bohemian 
  Museum, 
  Prague.] 
  

  

  Gyrodus 
  runcinatus, 
  L. 
  Agassiz, 
  ibid. 
  pt. 
  i. 
  (1833), 
  p. 
  16, 
  pt. 
  ii. 
  

   (1844), 
  p. 
  236, 
  pi. 
  lxix. 
  a. 
  fig. 
  19.— 
  Eorm. 
  and 
  loo. 
  un- 
  

   known. 
  [Stuttgart 
  Museum.] 
  

  

  Gyrodus 
  wannerius, 
  A. 
  Dollfuss, 
  Eaune 
  Kimm. 
  Cap 
  De 
  la 
  Heve, 
  

   (1863), 
  p. 
  35, 
  pi. 
  i. 
  figs. 
  17, 
  18 
  (name 
  said 
  to 
  have 
  been 
  

   originally 
  given 
  by 
  Lesueur 
  to 
  a 
  jaw 
  much 
  resembling 
  

   G. 
  jurassicus, 
  figured 
  on 
  a 
  rare 
  plate 
  " 
  Vues 
  et 
  coupes 
  

   de 
  la 
  Heve," 
  1843). 
  — 
  Kimmeridgian 
  ; 
  Normandy. 
  

  

  Genus 
  STEMMATODUS, 
  Heckel. 
  

  

  [Denkschr. 
  k. 
  Akad. 
  Wiss., 
  math.-naturw. 
  CI. 
  vol. 
  xi. 
  

  

  1856, 
  p. 
  202.] 
  

  

  Trunk 
  deeply 
  fusiform, 
  not 
  produced 
  at 
  the 
  caudal 
  pedicle. 
  Head 
  

   and 
  opercular 
  bones 
  tuberculated 
  ; 
  teeth 
  with 
  an 
  apical 
  indent 
  

   surrounded 
  by 
  a 
  crenulated 
  margin 
  ; 
  vomerine 
  teeth 
  in 
  five 
  longi- 
  

   tudinal 
  series, 
  and 
  splenial 
  teeth 
  in 
  three 
  series. 
  Neural 
  and 
  haemal 
  

   arches 
  of 
  axial 
  skeleton 
  of 
  trunk 
  not 
  expanding 
  sufficiently 
  to 
  encircle 
  

   the 
  notochord. 
  Ein-rays 
  delicate, 
  spaced, 
  and 
  articulated 
  in 
  the 
  

   dorsal 
  and 
  anal 
  fins 
  ; 
  stouter, 
  more 
  closely 
  articulated, 
  and 
  divided 
  

   distally 
  in 
  the 
  caudal 
  fin. 
  Pelvic 
  fins 
  present; 
  dorsal 
  and 
  anal 
  

   fins 
  low, 
  acuminate 
  in 
  front, 
  fringe-like 
  behind, 
  the 
  former 
  occupying 
  

   at 
  least 
  the 
  hinder 
  half 
  of 
  the 
  back, 
  and 
  the 
  latter 
  somewhat 
  shorter, 
  

   arising 
  more 
  posteriorly 
  ; 
  caudal 
  fin 
  with 
  straight 
  or 
  slightly 
  ex- 
  

   cavated 
  hinder 
  margin. 
  Scales 
  covering 
  only 
  the 
  anterior 
  half 
  of 
  

   the 
  trunk 
  in 
  advance 
  of 
  the 
  median 
  fins. 
  

  

  Stemmatodus 
  rhombus 
  (Agassiz). 
  

  

  1839-44. 
  Pycnodus 
  rhombus, 
  L. 
  Agassiz, 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  ii. 
  

  

  p. 
  188, 
  pi. 
  lxxii. 
  figs. 
  5-7. 
  

   1856. 
  Stemmatodus 
  rhombus, 
  J. 
  J. 
  Heckel, 
  Denkschr. 
  k. 
  Akad. 
  Wiss., 
  

  

  math.-naturw. 
  CI. 
  vol. 
  xi. 
  p. 
  202. 
  

   1856. 
  Stemmatodus 
  rhomboides, 
  J. 
  J. 
  Heckel, 
  ibid. 
  p. 
  205, 
  pi. 
  ii. 
  

  

  figs. 
  9-11. 
  [Nearly 
  complete 
  fish 
  ; 
  Royal 
  Bohemian 
  Museum, 
  

  

  Prague.] 
  

  

  