﻿86 
  ACTINOPTERYGII. 
  

  

  1837. 
  Lepidotus 
  semiserratus, 
  L. 
  Agassiz, 
  ibid. 
  p. 
  240, 
  pis. 
  xxix. 
  a, 
  b. 
  

   1849. 
  Lepidotus 
  semiserratus, 
  W. 
  0. 
  Williamson, 
  Phil. 
  Trans, 
  p. 
  441, 
  

   pi. 
  xl. 
  figs. 
  3, 
  4. 
  

  

  Type. 
  Imperfect 
  fishes 
  ; 
  Whitby 
  and 
  Scarborough 
  Museums. 
  

  

  An 
  imperfectly 
  known 
  species, 
  closely 
  related 
  to 
  the 
  typical 
  

   L. 
  elvensis, 
  but 
  apparently 
  distinguished 
  by 
  its 
  more 
  elongated 
  form, 
  

   the 
  maximum 
  depth 
  being 
  contained 
  four 
  times 
  in 
  the 
  total 
  length. 
  

   The 
  parietal 
  bones 
  also 
  seem 
  to 
  be 
  relatively 
  longer, 
  and 
  the 
  sutures 
  

   between 
  both 
  these 
  elements 
  and 
  the 
  frontals 
  more 
  wavy 
  and 
  

   sharply 
  angulated. 
  

  

  Form. 
  Sf 
  Log. 
  Upper 
  Lias 
  : 
  Yorkshire 
  \ 
  

  

  All 
  the 
  following 
  specimens 
  were 
  obtained 
  from 
  the 
  cliffs 
  near 
  

   Whitby 
  :— 
  

  

  P. 
  7409. 
  Imperfect 
  fish 
  about 
  0*55 
  in 
  length, 
  with 
  the 
  base 
  of 
  the 
  

   caudal 
  fin 
  and 
  fragments 
  of 
  the 
  dorsal 
  and 
  paired 
  fins. 
  

  

  P. 
  2012. 
  Larger 
  specimen, 
  exhibiting 
  the 
  ventral 
  and 
  partly 
  lateral 
  

   aspect, 
  with 
  portions 
  of 
  the 
  paired 
  and 
  aual 
  fins, 
  but 
  

   wanting 
  the 
  caudal. 
  Egerton 
  Coll. 
  

  

  P. 
  2012 
  a. 
  Head 
  and 
  trunk, 
  lateral 
  aspect, 
  with 
  well-preserved 
  

   squamation 
  and 
  remains 
  of 
  the 
  paired 
  fins. 
  Some 
  of 
  the 
  

   principal 
  flank-scales 
  are 
  coarsely 
  denticulated 
  upon 
  the 
  

   lower 
  half 
  of 
  their 
  hinder 
  border. 
  The 
  fulcra 
  both 
  of 
  the 
  

   pectoral 
  and 
  pelvic 
  fins 
  are 
  prominent 
  and, 
  though 
  im- 
  

   perfectly 
  preserved, 
  appear 
  to 
  have 
  been 
  double. 
  

  

  Egerton 
  Coll. 
  

  

  P. 
  3527. 
  Imperfect 
  fish, 
  lateral 
  aspect, 
  about 
  0-6 
  in 
  length, 
  dis- 
  

   playing 
  the 
  squamation. 
  Enniskillen 
  Coll. 
  

  

  P. 
  3528. 
  Two 
  specimens, 
  ventro-lateral 
  aspect, 
  showing 
  the 
  enlarged 
  

   scales 
  in 
  the 
  anal 
  region, 
  with 
  well- 
  displayed 
  remains 
  of 
  

   the 
  caudal, 
  anal, 
  and 
  paired 
  fins. 
  The 
  smaller 
  specimen 
  

   also 
  exhibits 
  some 
  of 
  the 
  marginal 
  teeth 
  of 
  the 
  upper 
  jaw. 
  

  

  Enniskillen 
  Coll. 
  

  

  P. 
  7410. 
  Head 
  of 
  a 
  large 
  individual 
  with 
  some 
  of 
  the 
  anterior 
  

   scales 
  and 
  the 
  base 
  of 
  the 
  pectoral 
  fins. 
  The 
  general 
  form 
  

   of 
  the 
  mandible 
  and 
  some 
  of 
  its 
  styliform 
  teeth 
  are 
  well 
  

   exhibited. 
  Purchased. 
  

  

  35556. 
  A 
  small 
  head, 
  with 
  some 
  of 
  the 
  anterior 
  scales 
  and 
  the 
  base 
  

   of 
  the 
  pectoral 
  fins. 
  Purchased, 
  1859. 
  

  

  1 
  Also 
  recorded 
  from 
  Boll, 
  Wiirtemberg, 
  by 
  F. 
  A. 
  Quenstedt, 
  Flozgeb. 
  

   Wiirttemb. 
  p. 
  234. 
  

  

  