﻿368 
  H. 
  G. 
  SEELET 
  ON 
  A 
  DINOSAUEIAN 
  CORACOID. 
  

  

  bone 
  is 
  of 
  moderate 
  thickness, 
  but 
  greatly 
  expanded 
  at 
  the 
  humeral 
  

   articulation. 
  Its 
  greatest 
  length 
  is 
  about 
  44 
  centim. 
  (17J- 
  in.) 
  ; 
  

   greatest 
  width 
  36 
  centim. 
  (14| 
  in.) 
  ; 
  and 
  the 
  greatest 
  (external) 
  length 
  

   of 
  the 
  humeral 
  articular 
  surface 
  is 
  20 
  centim. 
  (7 
  T 
  9 
  ^- 
  in.), 
  while 
  the 
  

   greatest 
  (internal) 
  length 
  of 
  the 
  suture 
  for 
  the 
  scapula 
  measures 
  

   about 
  27 
  centim. 
  (10 
  Jin.) 
  The 
  bone 
  gives 
  no 
  certain 
  evidence 
  of 
  union 
  

   with 
  a 
  sternum, 
  though 
  the 
  fact 
  that 
  the 
  extreme 
  posterior 
  end 
  of 
  the 
  

   internal 
  border 
  of 
  the 
  bone 
  is 
  thicker 
  (fig. 
  2, 
  r) 
  than 
  the 
  part 
  which 
  

   is 
  anterior 
  to 
  it 
  is 
  rather 
  in 
  favour 
  of 
  the 
  possibility 
  of 
  the 
  hinder 
  

   part 
  of 
  the 
  bone 
  having 
  had 
  such 
  an 
  osseous 
  relation. 
  But 
  the 
  great 
  

   thickening 
  of 
  the 
  internal 
  or 
  median 
  sutural 
  margin 
  in 
  a 
  line 
  trans- 
  

   versely 
  indicating 
  the 
  junction 
  of 
  the 
  coracoid 
  and 
  scapula 
  convinces 
  

   me 
  that 
  the 
  coracoids 
  there 
  met 
  in 
  the 
  median 
  line, 
  though 
  their 
  

   union 
  was 
  by 
  uo 
  means 
  firm. 
  As 
  a 
  whole, 
  the 
  bone 
  has 
  a 
  curious 
  

   general 
  resemblance 
  to 
  the 
  anterior 
  portion 
  of 
  an 
  ilium, 
  such 
  as 
  is 
  

   seen 
  in 
  some 
  of 
  the 
  large 
  American 
  types. 
  

  

  Fig. 
  2. 
  — 
  Contour 
  of 
  Median 
  Sutural 
  Margin 
  of 
  Dlnosaurian 
  

   Coracoid. 
  

  

  n 
  

  

  9H, 
  contour 
  of 
  external, 
  and 
  n, 
  internal 
  surfaces, 
  p 
  is 
  placed 
  at 
  the 
  

   imperfect 
  anterior 
  border, 
  r. 
  Posterior 
  border. 
  

  

  The 
  Median 
  Sutural 
  Margin 
  (fig. 
  2). 
  — 
  Though 
  the 
  lateral 
  outline 
  

   is 
  convex 
  as 
  a 
  whole 
  from 
  back 
  to 
  front, 
  it 
  is 
  straight 
  or 
  a 
  little 
  concave 
  

   for 
  a 
  length 
  of 
  about 
  27 
  centim. 
  (10J 
  in.) 
  in 
  the 
  middle, 
  where 
  the 
  

   bones 
  may 
  have 
  met 
  ; 
  and 
  the 
  diverging 
  posterior 
  margin 
  is 
  also 
  

   straightened 
  where 
  it 
  may 
  have 
  abutted 
  against 
  a 
  sternum. 
  This 
  

   surface 
  is 
  convex 
  from 
  within 
  outward, 
  and 
  roughened 
  with 
  trans- 
  

   verse 
  grooves, 
  parallel 
  and 
  more 
  or 
  less 
  irregular, 
  indicative 
  of 
  a 
  

   cartilaginous 
  surface 
  to 
  the 
  bone. 
  The 
  contour 
  of 
  this 
  surface, 
  as 
  

   seen 
  transversely 
  (fig. 
  2), 
  is 
  remarkably 
  like 
  that 
  of 
  a 
  ladle 
  with 
  the 
  

   bowl 
  in 
  front, 
  so 
  that 
  its 
  convexity 
  projects 
  outward 
  and 
  thickens 
  

   the 
  bone 
  to 
  5| 
  centim. 
  (2-i- 
  in.), 
  while, 
  owing 
  to 
  the 
  corresponding 
  

   though 
  lesser 
  internal 
  concavity, 
  it 
  tapers 
  forward. 
  But 
  immediately 
  

   behind 
  this 
  anterior 
  thickening 
  the 
  bone 
  is 
  compressed 
  to 
  a 
  thickness 
  

   of 
  2 
  centim. 
  (A 
  in.) 
  ; 
  and 
  here 
  the 
  external 
  surface 
  is 
  concave 
  and 
  the 
  

   internal 
  surface 
  is 
  convex 
  ; 
  then 
  succeeds 
  a 
  longer 
  external 
  curve 
  

   with 
  a 
  corresponding 
  internal 
  concavity 
  terminating 
  in 
  the 
  posterior 
  

   expansion 
  of 
  5^ 
  centim. 
  width 
  already 
  mentioned. 
  

  

  The 
  External 
  Surface 
  (fig. 
  1). 
  — 
  This 
  is 
  necessarily 
  irregular 
  to- 
  

   wards 
  the 
  median 
  line 
  (c), 
  with 
  the 
  folds 
  and 
  thickenings 
  of 
  the 
  

   bone 
  already 
  described, 
  which 
  somewhat 
  resemble 
  those 
  of 
  Colym- 
  

   bosaurus 
  and 
  certain 
  Plesiosaurs 
  where 
  these 
  bones 
  meet 
  in 
  the 
  

   median 
  line. 
  The 
  bone 
  is 
  18 
  centim. 
  (7^ 
  in.) 
  wide 
  proximally, 
  

   26 
  centim. 
  (10| 
  in.) 
  wide 
  in 
  the 
  middle 
  where 
  thickest, 
  and 
  from 
  

  

  