﻿168 
  ACTINOPTEKYGII. 
  

  

  caudal 
  pedicle. 
  Dorsal 
  fin 
  extending 
  about 
  half 
  the 
  length 
  of 
  the- 
  

   back 
  ; 
  pelvic 
  fins 
  arising 
  much 
  nearer 
  to 
  the 
  pectorals 
  than 
  to 
  the 
  

   caudal. 
  Scales 
  of 
  moderate 
  size, 
  smooth 
  and 
  delicately 
  serrated. 
  

  

  A 
  fish 
  from 
  the 
  Lithographic 
  Stone, 
  described 
  as 
  intermediate 
  

   between 
  this 
  species 
  and 
  0. 
  attenuata, 
  is 
  named 
  0. 
  intermedia 
  by 
  

   "Wagner, 
  loc. 
  cit. 
  p. 
  657. 
  The 
  type 
  specimen 
  is 
  a 
  well-preserved 
  fish 
  

   in 
  the 
  Palseontological 
  Museum, 
  Munich. 
  

  

  Form. 
  Sf 
  Loc. 
  Lower 
  Kimmeridgian 
  (Lithographic 
  Stone): 
  Ba- 
  

   varia. 
  

  

  P. 
  7176. 
  Fish 
  0135 
  in 
  length, 
  much 
  crushed, 
  the 
  dorsal 
  fin 
  and 
  

   squamation 
  shown 
  only 
  in 
  impression 
  ; 
  Eichstadt. 
  Granu- 
  

   lar 
  teeth 
  are 
  exhibited 
  apparently 
  on 
  the 
  splenial 
  and 
  

   pterygoid 
  bones 
  ; 
  and 
  about 
  12 
  branchiostegal 
  rays 
  are 
  

   shown 
  in 
  series. 
  The 
  length 
  of 
  the 
  pectoral 
  fin-rays 
  

   appears 
  to 
  be 
  nearly 
  equal 
  to 
  the 
  depth 
  of 
  the 
  back 
  of 
  the 
  

   head. 
  Purchased, 
  1894. 
  

  

  Ophiopsis 
  tenuis 
  err 
  at 
  a 
  (Agassiz). 
  

  

  1844. 
  Pholidophorus 
  tenuiserratus, 
  L. 
  Agassiz 
  (ex 
  Minister, 
  MS.),, 
  

  

  Poiss. 
  Foss. 
  vol. 
  ii. 
  pt. 
  i. 
  p. 
  276, 
  pi. 
  xxxviii. 
  fig. 
  3, 
  pi. 
  xlii. 
  fig. 
  4. 
  

   1851. 
  Ophiopsis 
  serratus, 
  A. 
  Wagner, 
  Abh. 
  k. 
  bay. 
  Akad. 
  Wiss., 
  math.- 
  

  

  phys. 
  01. 
  vol. 
  vi. 
  p. 
  62. 
  [Imperfect 
  fish 
  ; 
  Palaeontological 
  Museum,. 
  

  

  Munich.] 
  

   1863. 
  Ophiopsis 
  serrata, 
  A. 
  Wagner, 
  ibid. 
  vol. 
  ix. 
  p. 
  654. 
  

   1881. 
  Ophiopsis 
  serrata, 
  B. 
  Vetter, 
  Mittheil. 
  k. 
  mineral.-geol. 
  Mus. 
  

  

  Dresden, 
  pt. 
  iv. 
  p. 
  55. 
  

  

  Type. 
  Imperfect 
  fish 
  ; 
  Woodwardian 
  Museum, 
  Cambridge. 
  

  

  A 
  robust 
  species, 
  attaining 
  a 
  length 
  of 
  0*18. 
  Head 
  with 
  oper- 
  

   cular 
  apparatus 
  occupying 
  nearly 
  one-fifth 
  of 
  the 
  total 
  length 
  ; 
  

   maximum 
  depth 
  of 
  trunk 
  twice 
  as 
  great 
  as 
  the 
  width 
  of 
  the 
  caudal 
  

   pedicle 
  and 
  contained 
  five 
  times 
  in 
  the 
  total 
  length 
  of 
  the 
  fish. 
  

   Fin-fulcra 
  very 
  slender, 
  present 
  on 
  paired 
  fins. 
  Dorsal 
  fin 
  occupy- 
  

   ing 
  slightly 
  less 
  than 
  half 
  of 
  the 
  back 
  and 
  comprising 
  25 
  rays,, 
  

   mostly 
  bifurcated, 
  of 
  which 
  the 
  anterior 
  three 
  are 
  extremely 
  elon- 
  

   gated 
  (their 
  length 
  exceeding 
  the 
  depth 
  of 
  the 
  trunk) 
  and 
  the 
  

   others 
  rapidly 
  become 
  much 
  shortened 
  posteriorly 
  ; 
  pelvic 
  fins 
  

   arising 
  considerably 
  in 
  advance 
  of 
  the 
  middle 
  point 
  between 
  the 
  

   pectorals 
  and 
  caudal. 
  Scales 
  smooth, 
  those 
  of 
  the 
  flank 
  finely 
  

   serrated 
  and 
  partly 
  pectinated 
  at 
  the 
  hinder 
  margin, 
  except 
  towards 
  

   the 
  extremity 
  of 
  the 
  caudal 
  region. 
  

  

  Form. 
  Sf 
  Loc. 
  Lower 
  Kimmeridgian 
  (Lithographic 
  Stone) 
  : 
  Ba-< 
  

   varia. 
  

  

  