﻿324 
  ACTINOPTERTGII. 
  

  

  depth 
  of 
  the 
  trunk, 
  and 
  occupying 
  about 
  one-quarter 
  of 
  the 
  total 
  

   length 
  of 
  the 
  fish. 
  The 
  ornament 
  of 
  the 
  external 
  hones 
  consisting 
  

   of 
  closely 
  arranged 
  prominent 
  ridges 
  ; 
  the 
  scales 
  with 
  strongly 
  

   marked 
  longitudinal 
  ridges 
  and 
  furrows 
  terminating 
  in 
  posterior 
  

   denticulations, 
  and 
  with 
  some 
  conspicuous 
  vertical 
  folds 
  at 
  the 
  

   anterior 
  border. 
  

  

  Form. 
  &f 
  Loc. 
  Upper 
  Trias 
  : 
  Raibl, 
  Carinthia. 
  

  

  P. 
  5958. 
  A 
  typical 
  specimen 
  wanting 
  all 
  the 
  fins 
  except 
  the 
  dorsal 
  

   and 
  caudal, 
  but 
  displaying 
  the 
  squamation. 
  

  

  Purchased. 
  1889. 
  

  

  Ptycholepis 
  marshi, 
  Newberry. 
  

  

  1878. 
  Ptycholepis 
  marshii, 
  J. 
  S. 
  Newberry, 
  Ann. 
  New 
  York 
  Acad. 
  Sci. 
  

  

  vol. 
  i. 
  p. 
  127. 
  

   1888. 
  Ptycholepis 
  marshii, 
  J. 
  S. 
  Newberry, 
  Foss. 
  Fishes 
  Trias, 
  N. 
  

  

  Jersey 
  & 
  Connecticut 
  (Mon. 
  U.S. 
  Geol. 
  Surv. 
  no. 
  xiv.), 
  p. 
  66, 
  

  

  pi. 
  xix. 
  figs. 
  1, 
  2. 
  

  

  Type. 
  Nearly 
  complete 
  fish. 
  

  

  A 
  species 
  of 
  slender 
  proportions, 
  attaining 
  a 
  length 
  of 
  about 
  0'2. 
  

   Head 
  with 
  opercular 
  apparatus 
  occupying 
  somewhat 
  less 
  than 
  one- 
  

   quarter 
  of 
  the 
  total 
  length 
  of 
  the 
  fish. 
  Ornamental 
  rugae 
  on 
  cranial 
  

   roof 
  slightly 
  radiating; 
  those 
  of 
  the 
  facial 
  and 
  opercular 
  bones 
  

   more 
  or 
  less 
  parallel 
  and 
  forked. 
  Dorsal 
  fin 
  far 
  forwards, 
  and 
  

   pelvic 
  fins 
  arising 
  opposite 
  its 
  hinder 
  extremity. 
  Scales 
  exhibiting 
  

   only 
  longitudinal 
  ridges 
  and 
  furrows, 
  and 
  the 
  hinder 
  border 
  often 
  

   deeply 
  serrated. 
  {Newberry.) 
  

  

  Form. 
  Sf 
  Loc. 
  Trias 
  : 
  Durham, 
  Connecticut, 
  U.S.A. 
  

  

  Not 
  represented 
  in 
  the 
  Collection. 
  

  

  Some 
  detached 
  scales 
  from 
  the 
  Upper 
  Trias 
  of 
  Besano, 
  Lombardy, 
  

   are 
  also 
  named 
  Ptycholepis 
  barboi 
  by 
  F. 
  Bassani, 
  Atti 
  Soc. 
  Ital. 
  Sci. 
  

   Nat. 
  vol. 
  xxix. 
  (1886), 
  p. 
  38. 
  

  

  The 
  so-called 
  Ptycholepis 
  tenuisquamata 
  (R. 
  Kner, 
  Sitzungsb. 
  k. 
  

   Akad. 
  Wiss., 
  math.-naturw. 
  CI. 
  vol. 
  lvi. 
  pt. 
  i. 
  1867, 
  p. 
  913, 
  pi. 
  iv.) 
  

   from 
  the 
  Upper 
  Trias 
  of 
  Tlaibl, 
  Carinthia, 
  apparently 
  does 
  not 
  belong 
  

   to 
  this 
  genus. 
  

  

  Genus 
  OSTEORACHIS, 
  Egerton. 
  

  

  [Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xxiv. 
  1868, 
  p. 
  500.] 
  

  

  Syn. 
  Isocolum, 
  Sir 
  P. 
  Egerton, 
  ibid. 
  1868, 
  p. 
  501 
  . 
  

  

  Harpactes, 
  Sir 
  P. 
  Egerton 
  (worcTempleton, 
  1834), 
  Geol. 
  Mag. 
  [2] 
  

  

  vol. 
  iii. 
  1876, 
  p. 
  441. 
  

   Harpactira, 
  Sir 
  P. 
  Egerton, 
  ibid. 
  1876, 
  p. 
  576. 
  

  

  Trunk 
  elongate. 
  External 
  bones 
  ornamented 
  with 
  tuber 
  dilations 
  

   or 
  rugae 
  ; 
  marginal 
  teeth 
  relatively 
  large 
  and 
  well-spaced 
  ; 
  splenial 
  

  

  