﻿PACHYCOKMIDiE. 
  

  

  377 
  

  

  and 
  contained 
  seven 
  times 
  in 
  the 
  total 
  length. 
  Pelvic 
  fins 
  arising 
  a 
  

   little 
  in 
  advance 
  of 
  the 
  middle 
  point 
  between 
  the 
  pectoral 
  and 
  anal 
  

   fins; 
  dorsal 
  and 
  anal 
  fins 
  directly 
  opposed, 
  each 
  with 
  about 
  18 
  rays, 
  

   arising 
  somewhat 
  behind 
  the 
  middle 
  point 
  of 
  the 
  trunk. 
  Scales 
  

   smooth. 
  

  

  Form. 
  Sr 
  Log. 
  Upper 
  Lias 
  : 
  Yassy, 
  Yonne, 
  France. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Genus 
  EUTHYNOTUS, 
  Wagner. 
  

   [Gelehrte 
  Anzeig. 
  k. 
  bay. 
  Akad. 
  Wiss. 
  vol. 
  1. 
  1860, 
  p. 
  214.] 
  

  

  Syn. 
  Cyclospondylus, 
  F. 
  A. 
  Quenstedt, 
  Handb. 
  Petrefakt. 
  ed. 
  2, 
  1867, 
  

   p. 
  260. 
  

   Heterothrissops, 
  H. 
  E. 
  Sauvage, 
  Bibl. 
  Ecole 
  Hautes 
  Etudes, 
  

  

  vol. 
  xiii. 
  no. 
  5, 
  1875, 
  p. 
  46. 
  

   Pseudothrissops, 
  EL 
  E. 
  Sauvage, 
  ibid. 
  p. 
  46. 
  

   Parathrissops, 
  H. 
  E. 
  Sauvage, 
  Bull. 
  Soc. 
  Sci. 
  Yonne, 
  vol. 
  xlv. 
  

   pt. 
  ii. 
  1891, 
  p. 
  37. 
  

  

  A 
  genus 
  differing 
  only 
  from 
  Sauropsis 
  in 
  the 
  presence 
  of 
  well- 
  

   developed 
  hypocentra 
  and 
  pleurocentra 
  surrounding 
  the 
  notochord, 
  

   and 
  in 
  exhibiting 
  minute 
  fulcra 
  on 
  the 
  median 
  fins. 
  

  

  Euthynotus 
  incognitas 
  (Blainville). 
  

  

  1818. 
  Esox 
  incognitus, 
  H. 
  D. 
  de 
  Blainville, 
  Nouv. 
  Diet. 
  d'Hist. 
  Nat. 
  

  

  vol. 
  xxvii. 
  p. 
  325. 
  

   1833-44. 
  Thrissops 
  micropodius, 
  L. 
  Agassiz, 
  Poiss. 
  Eoss. 
  vol. 
  ii. 
  pt. 
  i. 
  

  

  p. 
  12 
  ; 
  pt. 
  ii. 
  p. 
  126, 
  pi. 
  lxv. 
  

   1848. 
  Sauropsis 
  micropodius, 
  C. 
  G. 
  Giebel, 
  Fauna 
  der 
  Vorwelt, 
  Fische, 
  

  

  p. 
  200. 
  

   1852. 
  Thrissops 
  micropodius, 
  F. 
  A. 
  Quenstedt, 
  Handb. 
  Petrefakt. 
  p. 
  218, 
  

  

  pi. 
  xvii. 
  fig. 
  18. 
  

   1858. 
  Thrissops 
  micropodius, 
  F. 
  A. 
  Quenstedt, 
  Der 
  Jura, 
  p. 
  237, 
  

  

  pi. 
  xxxiii. 
  figs. 
  3-7. 
  

   1860. 
  Euthynotus 
  micropodius, 
  A. 
  Wagner, 
  Gelehrte 
  Anzeig. 
  k. 
  bay. 
  

  

  Akad. 
  Wiss. 
  vol. 
  1. 
  p. 
  218. 
  

   1867. 
  Cyclospondylus, 
  F. 
  A. 
  Quenstedt, 
  Handb. 
  Petrefakt. 
  ed. 
  2, 
  p. 
  260. 
  

   1875. 
  Pseudothrissops 
  micropodius 
  (errore 
  micropterus), 
  H. 
  E. 
  Sauvage, 
  

  

  Bibl. 
  Ecole 
  Hautes 
  Etudes, 
  vol. 
  xiii. 
  no. 
  5, 
  p. 
  46. 
  

   1887. 
  Euthynotus 
  micropodius, 
  K. 
  A. 
  von 
  Zittel, 
  Handb. 
  Palasont. 
  

   vol. 
  iii. 
  p. 
  225, 
  woodc. 
  fig. 
  238. 
  

  

  Type. 
  Nearly 
  complete 
  fish 
  ; 
  Paris 
  Museum 
  of 
  Natural 
  History. 
  

  

  The 
  type 
  species, 
  attaining 
  a 
  length 
  of 
  about 
  0*35. 
  Length 
  of 
  

   head 
  with 
  opercular 
  apparatus 
  equalling 
  somewhat 
  more 
  than 
  one- 
  

   fifth 
  of 
  the 
  total 
  length 
  to 
  the 
  base 
  of 
  the 
  caudal 
  fin, 
  and 
  exceeding 
  

  

  