﻿"3?(3 
  ON 
  THE 
  OS 
  PUBIS 
  AND 
  ISCHIUM 
  OF 
  ORNITIIOPSIS 
  EUCAMEROTUS. 
  

  

  7. 
  Hulke, 
  J. 
  W. 
  Appendix 
  to 
  above 
  note. 
  Op. 
  cit. 
  vol. 
  xxviii. 
  

  

  p. 
  36 
  (1871). 
  

  

  (Eucamerotus, 
  Hulke, 
  identified 
  with 
  Ornitliopsis, 
  Seeley.) 
  

  

  8. 
  Owen, 
  B. 
  Botliriospondylus 
  magnus, 
  Monograph 
  Brit. 
  Foss. 
  

  

  Eept. 
  Alesozoic 
  Formation, 
  part 
  ii. 
  pi. 
  viii. 
  Pal. 
  Soc. 
  vol. 
  for 
  

   year 
  1875. 
  

  

  (Description 
  and 
  figure 
  of 
  fossil 
  in 
  Brit. 
  Mus. 
  no. 
  28362). 
  

   0. 
  Owen, 
  E. 
  Chondrosteosaurus 
  magnus, 
  synonym 
  Boihriospondylus 
  

   magnus. 
  Foss. 
  Eept. 
  AVealden 
  and 
  Purbeck 
  Formations, 
  supp. 
  

   no. 
  vii. 
  p. 
  7 
  (1876). 
  

  

  10. 
  Owen, 
  E. 
  On 
  the 
  Occurrence 
  in 
  JSorth 
  America 
  of 
  Rare 
  Extinct 
  

  

  Vertebrates 
  found 
  fragmentarily 
  in 
  England. 
  Part 
  I. 
  Resto- 
  

   ration 
  of 
  Chondrosteosaurus. 
  Ann. 
  & 
  Mag. 
  Nat. 
  Hist. 
  ser. 
  5, 
  

   vol. 
  ii. 
  p. 
  201, 
  pis. 
  x., 
  xi. 
  (1878). 
  

  

  11. 
  Hulke, 
  J. 
  AY. 
  Xote 
  (3rd) 
  on 
  Eucamerotus, 
  Hulke 
  (Ornithopsis, 
  

  

  H. 
  G. 
  Seelev). 
  Quart. 
  Journ. 
  Gteol. 
  Soc. 
  vol. 
  xxxv. 
  p. 
  572 
  

   (1879). 
  

  

  12. 
  Hulke, 
  J. 
  \Y. 
  Supplementary 
  Note 
  on 
  the 
  Vertebra} 
  of 
  Orni- 
  

  

  thopsis. 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xxxvi. 
  p. 
  31, 
  pis. 
  iii. 
  iv. 
  

   (1880). 
  

  

  EXPLANATION 
  OF 
  PLATE 
  XIV. 
  

  

  Fig. 
  1. 
  Pubife 
  and 
  Ischium 
  of 
  Ornithopsis 
  eucamerotus, 
  one 
  fourth 
  uat. 
  size. 
  

   P. 
  Os 
  pubis: 
  ac, 
  its 
  acetabular 
  part; 
  U, 
  its 
  iliac 
  part;/, 
  foramen 
  ; 
  

   v, 
  its 
  dilated 
  ventral 
  symphysial 
  end. 
  Is. 
  Ischium 
  : 
  the 
  letters 
  in- 
  

   dicate 
  the 
  same 
  parts 
  as 
  do 
  the 
  corresponding 
  letters 
  in 
  the 
  pubis. 
  

   2. 
  Pubis 
  of 
  Atlantosawrus 
  irrvmanis, 
  O. 
  C. 
  Marsh, 
  one 
  twentieth 
  natural 
  

   size. 
  77. 
  Ilium. 
  P. 
  Pubis. 
  Is. 
  Ischium. 
  (Copied, 
  reversed, 
  from 
  

   the 
  'American 
  Journal 
  of 
  Science 
  and 
  Arts." 
  ser. 
  3, 
  vol. 
  xvii. 
  pi. 
  vii. 
  

   fig. 
  2.) 
  

  

  Discussion. 
  

  

  Prof. 
  Seeley 
  asked 
  for 
  the 
  evidence 
  on 
  which 
  these 
  bones 
  were 
  

   referred 
  to 
  Ornithopsis. 
  He 
  agreed 
  with 
  the 
  author 
  as 
  to 
  the 
  

   similarity 
  of 
  this 
  and 
  certain 
  American 
  forms, 
  and 
  also 
  as 
  to 
  their 
  

   affinities 
  with 
  other 
  reptilian 
  types. 
  He 
  thought 
  the 
  evidence 
  should 
  

   have 
  been 
  given 
  on 
  which 
  it 
  was 
  proposed 
  to 
  separate 
  into 
  two 
  species 
  

   the 
  two 
  vertebra) 
  which 
  he 
  had 
  first 
  described 
  as 
  belonging 
  to 
  Orni- 
  

   tJiopsis 
  Hullcei, 
  as 
  supposed 
  by 
  Cope 
  and 
  the 
  author, 
  before 
  referring 
  

   these 
  pelvic 
  bones 
  to 
  cither 
  species, 
  supposing 
  them 
  to 
  be 
  distinct. 
  

  

  The 
  AuTnoit 
  replied 
  that 
  the 
  pelvic 
  bones 
  were 
  found 
  imbedded 
  in 
  

   the 
  same 
  block 
  with 
  several 
  vertebrie 
  of 
  Ornithopsis. 
  The 
  similar 
  

   American 
  pelvic 
  bones 
  were 
  associated 
  with 
  vertebra? 
  wonderfully 
  like 
  

   those 
  of 
  Ornithopsis. 
  He 
  thought 
  that 
  the 
  form 
  and 
  proportions 
  of 
  

   the 
  two 
  vertebra) 
  in 
  the 
  British 
  Museum, 
  on 
  which 
  the 
  genus 
  was 
  

   founded, 
  were 
  so 
  different 
  that 
  we 
  are 
  justified 
  in 
  believing 
  them 
  to 
  

   have 
  belonged 
  to 
  two 
  distinct 
  species. 
  

  

  