﻿Ornitho 
  saurian 
  Genus 
  Ornitlioclielrus. 
  551 
  

  

  exhibits 
  the 
  raised 
  and 
  roughened 
  surface 
  for 
  the 
  biceps 
  

   tendon 
  in 
  a 
  greater 
  degree 
  than 
  any 
  of 
  the 
  others 
  on 
  this 
  

   tablet. 
  

  

  Tablet 
  J. 
  «. 
  II. 
  The 
  seven 
  specimens 
  on 
  this 
  tablet 
  are 
  

   the 
  proximal 
  ends 
  of 
  ulnce. 
  No. 
  1 
  is 
  the 
  proximal 
  end 
  of 
  a 
  

   right 
  ulna 
  figured 
  by 
  Seeley, 
  pi. 
  ii, 
  hg. 
  8 
  [loc. 
  cit.), 
  as 
  the 
  

   proximal 
  end 
  of 
  radins. 
  It 
  is 
  much 
  smaller, 
  but 
  similar 
  to 
  

   Ornithodesmus 
  lutidens, 
  with 
  the 
  central 
  transverse 
  ridge 
  on 
  

   the 
  articular 
  surface 
  not 
  so 
  highly 
  developed. 
  This 
  ridge 
  

   and 
  the 
  margins 
  of 
  the 
  bone 
  on 
  the 
  postaxial 
  side 
  are 
  worn 
  

   away. 
  The 
  strong 
  longitudinal 
  ridge 
  on 
  the 
  centre 
  of 
  tlie 
  

   ventral 
  surface 
  of 
  the 
  shaft 
  is 
  also 
  destroyed, 
  but 
  its 
  base 
  is 
  

   well 
  seen. 
  A 
  pneumatic 
  foramen 
  occurs, 
  covered 
  by 
  a 
  

   small 
  daub 
  of 
  matrix, 
  near 
  the 
  articular 
  surface, 
  ventral 
  side, 
  

   as 
  in 
  Ornithodesmus 
  latidens. 
  

  

  Nos. 
  2, 
  3, 
  4, 
  5, 
  6 
  all 
  have 
  the 
  median 
  vertical 
  ridge 
  on 
  the 
  

   anterior 
  surface 
  of 
  the 
  shaft. 
  All 
  are 
  close 
  to 
  no. 
  1, 
  and 
  thus 
  

   near 
  to 
  Ornithodesmus, 
  but 
  the 
  ridges, 
  processes, 
  and 
  articular 
  

   characters 
  are 
  either 
  in 
  an 
  incipient 
  or 
  degraded 
  state. 
  

   No. 
  5 
  has 
  lost 
  the 
  median 
  area 
  of 
  the 
  articulation 
  in 
  such 
  a 
  

   manner 
  that 
  it 
  appears 
  at 
  tirst 
  sight 
  to 
  be 
  a 
  basin-shaped 
  

   depression, 
  whereas 
  a 
  closer 
  examination 
  proves 
  that 
  it 
  is 
  

   due 
  to 
  wear. 
  The 
  pneumatic 
  foramen 
  is 
  not 
  seen 
  in 
  nos. 
  2-6, 
  

   for 
  the 
  same 
  reason. 
  

  

  No. 
  7, 
  the 
  proximal 
  end 
  of 
  the 
  right 
  ulna, 
  figured 
  by 
  

   Seeley, 
  pi. 
  ii. 
  fig. 
  7 
  (/oc. 
  cit.), 
  is 
  remarkably 
  difi^erent 
  from 
  

   the 
  other 
  six 
  examples 
  on 
  this 
  tablet. 
  The 
  only 
  articular 
  

   surface 
  preserved 
  is 
  on 
  the 
  preaxial 
  side. 
  It 
  is 
  slightly 
  

   convex 
  and 
  looks 
  anteriorly. 
  The 
  dorsal 
  surface 
  and 
  post- 
  

   axial 
  border 
  are 
  destroyed. 
  There 
  is 
  no 
  pneumatic 
  foramen 
  

   on 
  the 
  portion 
  preserved. 
  The 
  great 
  peculiarity 
  of 
  this 
  

   specimen 
  is 
  on 
  the 
  ventral 
  surface, 
  where 
  the 
  bone 
  is 
  concave, 
  

   with 
  an 
  elongated 
  and 
  deep 
  pit 
  (no 
  foramen) 
  for 
  the 
  biceps 
  

   tendon 
  near 
  the 
  postaxial 
  border. 
  This 
  is 
  well 
  seen 
  in 
  the 
  

   figure. 
  The 
  other 
  pits 
  observed 
  are 
  not 
  natural, 
  but 
  the 
  

   borings 
  of 
  some 
  organism. 
  

  

  Distal 
  end. 
  

  

  Tablet 
  J. 
  a. 
  10, 
  1-10. 
  There 
  are 
  eleven 
  examples 
  on 
  this 
  

   tablet, 
  the 
  eleventh 
  probably 
  added 
  since 
  ' 
  Ornithosauria 
  ' 
  

   was 
  published. 
  They 
  are 
  the 
  distal 
  ends 
  of 
  ulnse, 
  and 
  not 
  

   " 
  radii.'' 
  Nos. 
  1, 
  2, 
  and 
  9 
  are 
  similar 
  in 
  character, 
  no. 
  2 
  is 
  

   the 
  best 
  specimen 
  and 
  figured 
  by 
  Seeley, 
  pi. 
  iii. 
  fig. 
  1 
  (Joe. 
  

   cit.). 
  On 
  the 
  major 
  portion 
  of 
  the 
  dorsal 
  surface, 
  towards 
  

   the 
  preaxial 
  side, 
  there 
  is 
  the 
  fiattened 
  surface, 
  against 
  which 
  

  

  