﻿314 
  ACTINOPTERYGIJ. 
  

  

  enlarged. 
  As 
  the 
  series 
  are 
  traced 
  backwards 
  the 
  peg- 
  

   and-socket 
  articulation 
  gradually 
  disappears, 
  while 
  the 
  

   inner 
  rib 
  widens 
  and 
  is 
  finally 
  indistinguishable. 
  

  

  Enniskillen 
  Coll. 
  

  

  The 
  following 
  species 
  have 
  also 
  been 
  imperfectly 
  defined, 
  but 
  do 
  

   not 
  appear 
  to 
  be 
  represented 
  in 
  the 
  Collection 
  : 
  — 
  

  

  Heterolepidotus 
  angulati, 
  W. 
  Deecke, 
  Mittheil. 
  Comm. 
  geol. 
  

  

  Landes-Untersuch. 
  Elsass-Lothr. 
  vol. 
  i. 
  (1888\ 
  p. 
  207. 
  — 
  

  

  Lower 
  Lias 
  ; 
  Buchsweiler, 
  Alsace. 
  [Nearly 
  complete 
  

  

  trunk 
  with 
  hinder 
  portion 
  of 
  head 
  ; 
  Geological 
  Survey 
  

  

  Museum, 
  Strassburg,] 
  

   Heterolepidotus 
  (?) 
  leptocephalus 
  : 
  Semionotus 
  leptocephalus, 
  L. 
  

  

  Agassiz, 
  Neues 
  Jahrb. 
  1832, 
  p. 
  145, 
  and 
  Poiss. 
  Foss. 
  

  

  vol. 
  ii. 
  pt. 
  i. 
  pp. 
  8, 
  222 
  (1833-44), 
  pi. 
  xxvi. 
  fig. 
  1 
  ; 
  

  

  F. 
  A. 
  Quenstedt, 
  Flozgeb. 
  Wiirttemb. 
  (1843), 
  p. 
  243 
  ; 
  0. 
  

  

  Fraas, 
  Wiirtt. 
  Jahresh. 
  1861, 
  p. 
  83. 
  — 
  Upper 
  Lias; 
  Boll, 
  

  

  Wiirtemberg. 
  [Nearly 
  complete 
  fish; 
  unknown.] 
  

   Heterolepidotus 
  minor, 
  J. 
  W. 
  Davis, 
  Proc. 
  Yorksh. 
  Geol. 
  & 
  Polyt. 
  

  

  Soc. 
  n. 
  s. 
  vol. 
  viii. 
  (1883), 
  p. 
  403, 
  pi. 
  xxii. 
  — 
  Lower 
  Lias 
  ; 
  

  

  Lyme 
  Regis. 
  [Fish 
  too 
  imperfect 
  for 
  specific 
  definition 
  ; 
  

  

  J. 
  W. 
  Davis 
  Collection, 
  Halifax.] 
  

  

  A 
  fish 
  closely 
  resembling 
  Heterolepidotus 
  but 
  differing 
  in 
  not 
  

   having 
  the 
  tail 
  forked, 
  is 
  known 
  from 
  the 
  Lower 
  Oolite 
  of 
  Brora, 
  

   Sutherland. 
  It 
  is 
  believed 
  to 
  have 
  been 
  obtained 
  from 
  the 
  carbon- 
  

   aceous 
  shale 
  underlying 
  the 
  main 
  seam 
  of 
  lignite 
  in 
  Strath 
  Brora, 
  

   and 
  the 
  original 
  specimens 
  are 
  now 
  in 
  the 
  Duke 
  of 
  Sutherland's 
  

   Museum 
  at 
  Dunrobin 
  Castle. 
  The 
  fish 
  has 
  been 
  described 
  under 
  

   the 
  name 
  of 
  Semionotus 
  joassi 
  (A. 
  S. 
  Woodward, 
  Ann. 
  Mag. 
  Nat. 
  

   Hist. 
  [5] 
  vol. 
  xx. 
  1887, 
  p. 
  179, 
  pi. 
  viii.), 
  but 
  its 
  generic 
  position 
  

   must 
  still 
  be 
  regarded 
  as 
  undetermined 
  (W. 
  Deecke, 
  Palaeontogr. 
  

   vol. 
  xxxv. 
  p. 
  103). 
  The 
  detached 
  maxilla 
  ascribed 
  to 
  it 
  (Joe. 
  cit. 
  

   pi. 
  viii. 
  fig. 
  3) 
  is 
  probably 
  named 
  erroneously, 
  and 
  seems 
  to 
  belong 
  

   to 
  a 
  Palaeoniscid. 
  

  

  A 
  generically 
  indeterminable 
  portion 
  of 
  squamation 
  which 
  may 
  

   belong 
  either 
  to 
  the 
  Palaeoniscidge 
  or 
  to 
  a 
  fish 
  resembling 
  Eugnathus 
  

   and 
  Heterolepidotus 
  is 
  described 
  as 
  follows 
  : 
  — 
  

  

  Greyiilepis 
  sandbergeri, 
  W. 
  Dames, 
  Palaeont. 
  Abhandl. 
  vol. 
  iv. 
  

   (1888), 
  p. 
  170, 
  pi. 
  xv. 
  fig. 
  3. 
  — 
  Muschelkalk 
  ; 
  Krainberg, 
  

   near 
  Wiirzburg. 
  [Abdominal 
  flank-squamation 
  ; 
  Univer- 
  

   sity 
  of 
  Wiirzburg.] 
  

  

  