﻿414 
  ACTINOPTERYGII. 
  

  

  originally 
  regarded 
  by 
  Cope 
  {toe. 
  cit. 
  1875, 
  p. 
  244 
  a) 
  as 
  representing 
  

   a 
  previously 
  unknown 
  order 
  of 
  Actinopterygian 
  fishes, 
  named 
  Acti- 
  

   nochiri. 
  The 
  American 
  specimens 
  are 
  described 
  as 
  exhibiting 
  " 
  six 
  

   single 
  and 
  one 
  paired 
  basilar 
  bones 
  supporting 
  the 
  pectoral 
  fin, 
  and 
  

   all 
  articulating 
  with 
  the 
  scapula." 
  The 
  following 
  forms, 
  not 
  repre- 
  

   sented 
  in 
  the 
  Collection, 
  are 
  distinguished 
  : 
  — 
  

  

  Pelecopterus 
  chirurgus, 
  E. 
  D. 
  Cope, 
  Yert. 
  Cret. 
  Eorm. 
  West 
  (Rep. 
  

  

  U.S. 
  Geol. 
  Surv. 
  Territ. 
  vol. 
  ii. 
  1875), 
  p. 
  244 
  e, 
  woodc. 
  

  

  fig. 
  10, 
  pi. 
  xlviii. 
  fig. 
  1, 
  pi. 
  liv. 
  fig. 
  9. 
  — 
  Upper 
  Cretaceous 
  

  

  (Niobrara 
  Group) 
  ; 
  Kansas. 
  

   Pelecopterus 
  gladius, 
  E. 
  D. 
  Cope, 
  he. 
  cit. 
  (1875), 
  p. 
  244 
  e, 
  pi. 
  Hi. 
  

  

  fig. 
  3, 
  pi. 
  xliv. 
  fig. 
  12 
  : 
  Portheus 
  gladius, 
  E. 
  D. 
  Cope, 
  

  

  Proc. 
  Acad. 
  Nat. 
  Sci. 
  Philad. 
  1873, 
  p. 
  338, 
  and 
  Bull. 
  U.S. 
  

  

  Geol. 
  Surv. 
  Territ; 
  vol. 
  i. 
  no. 
  2 
  (1874), 
  p. 
  40.— 
  Ibid. 
  

   Pelecopterus 
  perniciosus, 
  E. 
  D. 
  Cope, 
  loc. 
  cit. 
  (1875), 
  p. 
  244 
  d, 
  

  

  pi. 
  xlviii. 
  fig. 
  2, 
  pi. 
  lii. 
  fig. 
  2, 
  pi. 
  xliv. 
  fig. 
  13 
  : 
  Ichthyo- 
  

  

  dectes 
  perniciosus, 
  E. 
  D. 
  Cope, 
  Bull. 
  U.S. 
  Geol. 
  Surv. 
  Territ. 
  

  

  vol. 
  i. 
  no. 
  2 
  (1874), 
  p. 
  41. 
  — 
  Ibid. 
  [The 
  type 
  species 
  of 
  

  

  Pelecopterus, 
  referred 
  to 
  ProtospTiyrcena 
  nitida 
  by 
  A. 
  R. 
  

  

  Crook, 
  Palaaontogr. 
  vol. 
  xxxix. 
  (1892), 
  p. 
  110.] 
  

  

  To 
  the 
  Pachycormidaa 
  may 
  also 
  perhaps 
  be 
  referred 
  the 
  large 
  

   problematical 
  fish 
  from 
  the 
  Oxford 
  Clay 
  of 
  Peterborough 
  named 
  

   Leedsia 
  problematica 
  (A. 
  S. 
  Woodward, 
  Geol. 
  Mag. 
  [3] 
  vol. 
  vi. 
  1889, 
  

   p. 
  451 
  [Leedsichthys 
  problematicus~], 
  and 
  ibid. 
  vol. 
  vii. 
  1890, 
  p. 
  292, 
  

   pi. 
  x. 
  figs. 
  9, 
  10). 
  The 
  type 
  specimens 
  from 
  the 
  Leeds 
  Collection 
  

   are 
  now 
  preserved 
  in 
  the 
  Museum, 
  but 
  the 
  determination 
  of 
  all 
  the 
  

   bones 
  except 
  the 
  gill-rakers 
  (? 
  or 
  gill-supports) 
  is 
  still 
  so 
  uncertain, 
  

   that 
  it 
  seems 
  advisable 
  to 
  postpone 
  the 
  description 
  of 
  them 
  until 
  the 
  

   final 
  Supplement, 
  when 
  more 
  satisfactory 
  evidence 
  of 
  their 
  true 
  

   nature 
  may 
  perhaps 
  be 
  forthcoming. 
  The 
  massive 
  bones, 
  which 
  

   have 
  been 
  compared 
  with 
  branchiostegal 
  rays, 
  will 
  most 
  likely 
  prove 
  

   to 
  be 
  vertebral 
  arches. 
  The 
  genus 
  also 
  occurs 
  in 
  the 
  Oxford 
  Clay 
  

   of 
  Vaches 
  Noires, 
  Normandy, 
  and 
  in 
  the 
  Kimmeridge 
  Clay 
  of 
  

   Dorsetshire. 
  

  

  