﻿338 
  ACT1N0PTERYGII. 
  

  

  Bugey, 
  pt. 
  ii. 
  p. 
  17, 
  pi. 
  xii. 
  fig. 
  1. 
  [Nearly 
  complete 
  fish 
  ; 
  Lyons 
  

   Museum.] 
  

   1881. 
  " 
  Caturus 
  " 
  segusianus, 
  B. 
  Vetter, 
  Mittheil. 
  k. 
  mineral. 
  -geol. 
  Mus. 
  

   Dresden, 
  pt. 
  iv. 
  p. 
  110. 
  

  

  Type. 
  Nearly 
  complete 
  fish 
  ; 
  Lyons 
  Museum. 
  

  

  A 
  large 
  species, 
  attaining 
  a 
  length 
  of 
  about 
  0*5. 
  Length 
  of 
  head 
  

   with 
  opercular 
  apparatus 
  about 
  equal 
  to 
  the 
  maximum 
  depth 
  of 
  the 
  

   trunk, 
  and 
  less 
  than 
  one-quarter 
  of 
  the 
  total 
  length 
  of 
  the 
  fish. 
  

   Caudal 
  region 
  tapering 
  to 
  a 
  comparatively 
  slender 
  pedicle, 
  its 
  depth 
  

   equalling 
  about 
  one-third 
  the 
  maximum 
  depth 
  of 
  the 
  abdominal 
  

   region. 
  Teeth 
  smaller 
  than 
  in 
  the 
  type 
  species. 
  Dorsal 
  fin 
  deeper 
  

   than 
  long, 
  and 
  its 
  depth 
  nearly 
  or 
  quite 
  equalling 
  that 
  of 
  the 
  trunk 
  

   at 
  its 
  origin 
  ; 
  this 
  fin 
  arising 
  well 
  in 
  advance 
  of 
  the 
  middle 
  of 
  the 
  

   back, 
  the 
  distance 
  from 
  the 
  occiput 
  to 
  its 
  origin 
  being 
  considerably 
  

   less 
  than 
  that 
  from 
  its 
  hinder 
  border 
  to 
  the 
  base 
  of 
  the 
  caudal 
  fin. 
  

   Pelvic 
  fins 
  arising 
  opposite 
  the 
  hinder 
  half 
  of 
  the 
  dorsal 
  fin 
  ; 
  anal 
  

   fin 
  much 
  smaller 
  than 
  the 
  dorsal 
  ; 
  lobes 
  of 
  the 
  caudal 
  fin 
  especially 
  

   slender. 
  Scales 
  larger 
  than 
  in 
  the 
  type 
  species, 
  smooth. 
  

  

  The 
  peg-and-socket 
  articulation 
  of 
  the 
  scales 
  indicated 
  in 
  

   Thiolliere's 
  figure, 
  is 
  not 
  shown 
  in 
  the 
  specimens 
  enumerated 
  

   below. 
  

  

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

   France. 
  

  

  P. 
  905. 
  Fine 
  large 
  specimen 
  ; 
  Cirin. 
  Egerton 
  Coll. 
  

  

  P. 
  4700. 
  Smaller 
  and 
  more 
  imperfect 
  specimen, 
  the 
  trunk 
  shown 
  

   chiefly 
  in 
  impression 
  ; 
  Cirin. 
  Purchased, 
  1884. 
  

  

  P. 
  4697-8. 
  Two 
  imperfect 
  large 
  specimens 
  about 
  0*54 
  in 
  length, 
  

   for 
  the 
  most 
  part 
  shown 
  only 
  in 
  impression, 
  probably 
  of 
  

   this 
  species; 
  Cirin. 
  Purchased, 
  1884. 
  

  

  Caturus 
  velifer, 
  Thiolliere. 
  

  

  1850. 
  Caturus 
  velifer, 
  V. 
  Thiolliere, 
  Ann. 
  Sci. 
  Phys. 
  & 
  Nat. 
  Lyon, 
  [2] 
  

  

  vol. 
  iii. 
  p. 
  143. 
  

   1873. 
  Caturus 
  velifer, 
  V. 
  Thiolliere, 
  Poiss. 
  Foss. 
  Bugey, 
  pt. 
  ii. 
  p. 
  17, 
  

  

  pi. 
  xii. 
  fig. 
  2. 
  

   1881. 
  "Caturus" 
  velifer, 
  B. 
  Vetter, 
  Mittheil. 
  k. 
  mineral.-geol. 
  Mus. 
  

  

  Dresden, 
  pt. 
  iv. 
  p. 
  110. 
  

  

  Type. 
  Nearly 
  complete 
  fish 
  ; 
  Lyons 
  Museum. 
  

  

  A 
  large 
  species, 
  closely 
  related 
  to 
  C. 
  driani, 
  but 
  distinguished 
  by 
  

   its 
  more 
  elongated 
  trunk, 
  the 
  length 
  of 
  the 
  head 
  with 
  opercular 
  

   apparatus 
  exceeding 
  the 
  maximum 
  depth 
  of 
  the 
  trunk, 
  and 
  the 
  

  

  