﻿522 
  J. 
  W. 
  HULKE 
  ON 
  A 
  MODIFIED 
  FOBM 
  OF 
  DINOSADKIAK 
  ILIUM. 
  

  

  strong 
  transverse 
  acromial 
  ridge 
  which 
  overhangs 
  the 
  glenoid 
  depres- 
  

   sion, 
  and 
  in 
  the 
  deeper 
  concavity 
  of 
  the 
  posterior 
  margin 
  of 
  the 
  as- 
  

   cending 
  plate 
  or 
  body 
  of 
  the 
  bone. 
  This 
  part, 
  in 
  its 
  shape, 
  relative 
  

   length 
  and 
  breadth, 
  is 
  intermediate 
  between 
  the 
  crocodilian 
  and 
  lacer- 
  

   tian 
  type 
  of 
  the 
  scapula, 
  at 
  least 
  as 
  exemplified 
  in 
  the 
  Monitors 
  and 
  

   Iguanas. 
  The 
  Seines 
  and 
  Chameleons 
  in 
  the 
  more 
  crocodilian 
  pro- 
  

   portions 
  of 
  their 
  scapulas 
  resemble 
  the 
  Hylseosaur 
  and 
  the 
  great 
  

   species 
  of 
  extinct 
  Saurians, 
  most 
  probably 
  the 
  Iguanodon, 
  to 
  which 
  

   the 
  present 
  bone 
  belongs." 
  (" 
  Reports 
  on 
  British 
  Fossil 
  Reptiles," 
  in 
  

   Brit. 
  Assoc. 
  Bep. 
  1841, 
  p. 
  133.) 
  

  

  Having 
  subsequently 
  discovered 
  a 
  scapula 
  of 
  a 
  different 
  shape, 
  the 
  

   coracoid 
  border 
  of 
  which 
  he 
  saw 
  to 
  be 
  adapted 
  to 
  that 
  of 
  an 
  unequi- 
  

   vocal 
  Iguanodon 
  coracoid, 
  and 
  having 
  verified 
  his 
  new 
  acquisition 
  by 
  

   identifying 
  it 
  with 
  a 
  pair 
  of 
  bones 
  in 
  the 
  type 
  slab 
  of 
  the 
  Maidstone 
  

   Iguanodon, 
  Mantell 
  abandoned 
  his 
  original 
  reference 
  of 
  the 
  first 
  sca- 
  

   pula 
  to 
  this 
  herbivorous 
  Saurian, 
  but 
  he 
  continued 
  to 
  regard 
  it 
  as 
  a 
  

   scapula. 
  In 
  his 
  ' 
  Fossils 
  of 
  the 
  British 
  Museum,' 
  1851 
  , 
  at 
  pp. 
  282, 
  

   283, 
  he 
  reproduced 
  from 
  the 
  ' 
  Phil. 
  Trans.' 
  1841 
  his 
  first 
  description 
  

   of 
  it, 
  under 
  the 
  new 
  title 
  " 
  Scapula 
  of 
  an 
  unknown 
  Reptile." 
  

  

  MantelPs 
  determination 
  of 
  the 
  genuine 
  Iguanodon 
  scapula 
  was 
  soon 
  

   confirmed 
  by 
  Mr. 
  G. 
  B. 
  Holmes's 
  valuable 
  discovery, 
  near 
  Horsham, 
  

   of 
  an 
  Iguanodon 
  scapula 
  in 
  union 
  with 
  its 
  coracoid. 
  These 
  bones 
  

   were 
  described 
  and 
  figured 
  by 
  Prof. 
  Owen 
  in 
  his 
  monograph 
  on 
  the 
  

   Iguanodon 
  in 
  the 
  ' 
  Memoirs 
  of 
  the 
  Palseont. 
  Soc.,' 
  issued 
  in 
  1855. 
  

   In 
  the 
  following 
  year, 
  in 
  a 
  monograph 
  on 
  Megalosaurus, 
  in 
  the 
  same 
  

   Society's 
  Memoirs, 
  Prof. 
  Owen, 
  "with 
  a 
  full 
  sense 
  of 
  the 
  inadequacy 
  

   of 
  our 
  present 
  evidence 
  for 
  the 
  precise 
  determination 
  of 
  its 
  scapula," 
  

   assigned 
  to 
  this 
  Dinosaur 
  a 
  more 
  perfect 
  example 
  of 
  MantelPs 
  first 
  

   scapula, 
  discovered 
  at 
  Stammerham 
  by 
  G. 
  B. 
  Holmes, 
  Esq. 
  

  

  This 
  second 
  specimen 
  is 
  thus 
  described 
  : 
  — 
  " 
  The 
  body 
  of 
  the 
  bone 
  

   is 
  an 
  oblong 
  flattened 
  plate 
  proportionally 
  broader 
  and 
  stouter 
  than 
  

   in 
  Iguanodon, 
  with 
  the 
  base 
  rounded, 
  not 
  truncate 
  as 
  in 
  Hylceosaurus, 
  

   and 
  with 
  the 
  anterior 
  border 
  at 
  first, 
  as 
  it 
  descends, 
  straight, 
  and 
  

   then 
  concave, 
  not 
  convex 
  as 
  in 
  Hyloeosaurus. 
  The 
  body 
  of 
  the 
  sca- 
  

   pula 
  decreases 
  in 
  breadth 
  as 
  it 
  approaches 
  the 
  articular 
  end, 
  near 
  

   which 
  there 
  is 
  continued 
  from 
  the 
  anterior 
  border 
  a 
  long 
  and 
  slender 
  

   process 
  at 
  least 
  three 
  fourths 
  the 
  length 
  of 
  the 
  entire 
  bone, 
  but 
  the 
  

   precise 
  proportions 
  of 
  which 
  cannot 
  be 
  determined 
  in 
  this 
  specimen, 
  

   because 
  the 
  extremity 
  of 
  the 
  process 
  is 
  broken 
  off. 
  Near 
  the 
  base 
  

   of 
  the 
  process 
  a 
  tuberous 
  projection 
  is 
  developed, 
  which 
  touches 
  the 
  

   anterior 
  end 
  of 
  the 
  articular 
  end 
  of 
  the 
  scapula, 
  circumscribing 
  an 
  

   elliptical 
  vacuity, 
  probably 
  for 
  the 
  transmission 
  of 
  vessels. 
  The 
  

   thickened 
  articular 
  extremity 
  shows 
  indications 
  of 
  a 
  division 
  into 
  two 
  

   surfaces, 
  one 
  for 
  the 
  coracoid, 
  the 
  other 
  for 
  the 
  humerus." 
  

  

  The 
  figure 
  of 
  this 
  specimen 
  (tab. 
  v. 
  fig. 
  1) 
  is 
  explained 
  to 
  be 
  one 
  

   fourth 
  of 
  the 
  natural 
  size. 
  Mr. 
  Holmes 
  writes 
  to 
  me 
  that 
  this 
  is 
  an 
  

   error 
  ; 
  it 
  is 
  accurately 
  drawn 
  from 
  exact 
  measurements. 
  

  

  To 
  me 
  the 
  ' 
  Scapula 
  of 
  an 
  unknown 
  Beptile 
  ' 
  was 
  an 
  enigma 
  from 
  

   the 
  time 
  I 
  first 
  began 
  to 
  study 
  the 
  Dinosauria 
  ; 
  for 
  on 
  the 
  supposi- 
  

   tion 
  that 
  it 
  belonged 
  to 
  Megalosaurus, 
  which 
  its 
  place 
  in 
  the 
  National 
  

  

  