﻿SEMIONOTID^l. 
  151 
  

  

  Dapedius 
  magnevillei, 
  

  

  1833-36. 
  Tetragonolepis 
  magneville, 
  L. 
  Agassiz, 
  Poiss. 
  Foss. 
  vol. 
  ii. 
  

  

  pt. 
  i. 
  pp. 
  7, 
  214, 
  pi. 
  xxiv. 
  

   1852. 
  Dapedius 
  magneville, 
  F. 
  A. 
  Quenstedt, 
  Handb. 
  Petrefakt. 
  p. 
  203. 
  

  

  Type. 
  Nearly 
  complete 
  fish 
  ; 
  Caen 
  Museum. 
  

  

  A 
  species 
  of 
  moderate 
  size. 
  Maximum 
  depth 
  of 
  trunk 
  equal 
  to 
  

   its 
  length 
  (exclusive 
  of 
  the 
  caudal 
  fin) 
  and 
  about 
  six 
  times 
  as 
  great 
  

   as 
  the 
  depth 
  of 
  the 
  caudal 
  pedicle. 
  Head 
  with 
  opercular 
  apparatus 
  

   occupying 
  much 
  less 
  than 
  one-quarter 
  of 
  the 
  total 
  length 
  of 
  the 
  

   fish; 
  the 
  external 
  bones 
  ornamented 
  with 
  distinct 
  tuberculations. 
  

   All 
  the 
  scales, 
  except 
  those 
  towards 
  the 
  end 
  of 
  the 
  tail, 
  ornamented 
  

   with 
  sparsely 
  arranged 
  tubercles. 
  

  

  Form. 
  Sj- 
  Loc. 
  Upper 
  Lias 
  : 
  Normandy. 
  

  

  P. 
  7431. 
  Very 
  imperfectly 
  preserved 
  fish, 
  about 
  0-33 
  in 
  length 
  ; 
  said 
  

   to 
  have 
  been 
  obtained 
  from 
  Caen, 
  but 
  probably 
  from 
  

   Curcy. 
  Tesson 
  Coll. 
  

  

  As 
  already 
  pointed 
  out 
  (A. 
  S. 
  "Woodward, 
  Ann. 
  Mag. 
  Nat. 
  Hist. 
  

   [6] 
  vol. 
  i. 
  1888, 
  p. 
  356), 
  vertically 
  crushed 
  specimens 
  of 
  Dapedius 
  

   form 
  the 
  basis 
  of 
  the 
  so-called 
  genus 
  Amblyurus 
  (L. 
  Agassiz, 
  

   Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  i. 
  1836, 
  p. 
  220). 
  A 
  single 
  species, 
  A. 
  macro- 
  

   stomus 
  (Agassiz, 
  ibid. 
  p. 
  220, 
  pi. 
  xxv. 
  e), 
  is 
  founded 
  upon 
  specimens 
  

   from 
  the 
  Lower 
  Lias 
  of 
  Lyme 
  Eegis, 
  now 
  in 
  the 
  Oxford 
  Museum 
  : 
  

   and 
  the 
  following 
  are 
  similar 
  fossils 
  which 
  can 
  only 
  be 
  generically 
  

   determined 
  : 
  — 
  

  

  35564, 
  35788. 
  Two 
  crushed 
  and 
  distorted 
  fishes 
  showing 
  ventral 
  

   aspect, 
  the 
  first 
  small, 
  the 
  second 
  large 
  and 
  displaying 
  

   bifid 
  teeth 
  ; 
  Lower 
  Lias, 
  Lyme 
  Eegis. 
  Purchased, 
  1860. 
  

  

  36338. 
  Another 
  example, 
  ventral 
  aspect, 
  wanting 
  tail 
  but 
  showing 
  

   bifid 
  teeth 
  ; 
  Lyme 
  Eegis. 
  Purchased, 
  1862. 
  

  

  P. 
  1562. 
  Similar 
  specimen, 
  showing 
  paired 
  fins 
  anduniserial 
  fulcra 
  ; 
  

   Lyme 
  Eegis. 
  Egerton 
  Coll. 
  

  

  P. 
  3574. 
  Two 
  more 
  fragmentary 
  specimens, 
  ventral 
  aspect, 
  showing 
  

   the 
  caudal 
  fin 
  ; 
  Lyme 
  Eegis. 
  Enniskillen 
  Coll. 
  

  

  P. 
  2024. 
  More 
  imperfect 
  smaller 
  example, 
  labelled 
  by 
  Agassiz 
  ; 
  

   Lower 
  Lias, 
  Street, 
  Somersetshire. 
  Egerton 
  Coll. 
  

  

  The 
  following 
  fragmentary 
  specimens 
  of 
  Dapedius, 
  though 
  also 
  

   specifically 
  indeterminable, 
  are 
  of 
  interest 
  as 
  illustrating 
  anatomical 
  

   characters 
  or 
  showing 
  the 
  distribution 
  of 
  the 
  genus 
  : 
  — 
  

  

  