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  J. 
  W. 
  HULKE 
  ON 
  A 
  REPTILIAN 
  TIBIA 
  AND 
  HUMERUS. 
  

  

  of 
  its 
  contemporaries. 
  I 
  need 
  hardly 
  say 
  that 
  the 
  bone 
  which 
  

   Mantell 
  originally 
  regarded 
  as 
  the 
  humerus 
  of 
  Hylceosaurus 
  was 
  

   shown 
  by 
  Prof. 
  Owen 
  to 
  be 
  its 
  tibia. 
  There 
  is 
  also 
  in 
  the 
  National 
  

   Collection 
  a 
  bone 
  labelled 
  " 
  Humerus 
  of 
  Hylceosaurus 
  •" 
  but 
  both 
  ex- 
  

   tremities 
  are 
  so 
  mutilated 
  that 
  the 
  determination 
  is 
  more 
  than 
  doubt- 
  

   ful 
  .; 
  if 
  correct, 
  the 
  bone 
  must 
  have 
  belonged 
  to 
  a 
  very 
  immature 
  in- 
  

   dividual. 
  

  

  Supposing 
  that 
  Dr. 
  Wilkins's 
  specimen 
  should 
  prove 
  to 
  be 
  the 
  

   genuine 
  humerus 
  of 
  Hylceosaurus, 
  it 
  is 
  evident, 
  on 
  the 
  assumption 
  that 
  

   it 
  and 
  the 
  tibia 
  belonged 
  to 
  one 
  individual, 
  that 
  the 
  proportions 
  of 
  the 
  

   fore 
  and 
  hind 
  limbs 
  must 
  have 
  been 
  very 
  different 
  from 
  those 
  which 
  

   obtain 
  in 
  Iguanodon 
  and 
  Megalosaurus, 
  in 
  both 
  which 
  the 
  fore 
  limbs 
  

   are, 
  relatively 
  to 
  the 
  hind 
  limbs, 
  remarkably 
  reduced. 
  

  

  EXPLANATION 
  OF 
  PLATE 
  XXXI. 
  

  

  Beptilian 
  Tibia 
  and 
  Humerus. 
  

  

  Fig. 
  1. 
  Front 
  view 
  of 
  tibia 
  : 
  pr. 
  proximal, 
  d. 
  distal 
  end 
  ; 
  o. 
  m. 
  outer 
  malleolus 
  ; 
  

   i. 
  m. 
  inner 
  malleolus 
  ; 
  pre. 
  prascnemial 
  crest. 
  

  

  2. 
  Back 
  view 
  of 
  the 
  same 
  tibia. 
  

  

  3. 
  Oblique 
  view 
  of 
  ventral 
  surface 
  of 
  humerus 
  : 
  c. 
  capitulum 
  ; 
  r. 
  radial 
  

  

  condyle 
  ; 
  d. 
  deltoid 
  border. 
  

  

  4. 
  Dorsal 
  surface 
  of 
  the 
  same. 
  

  

  