﻿92 
  

  

  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  Fig. 
  27. 
  There 
  was 
  when 
  the 
  bone 
  was 
  complete, 
  a 
  

  

  double 
  head, 
  the 
  anterior 
  or 
  superior 
  apparently 
  

   for 
  articulation 
  with 
  the 
  coracoid 
  ; 
  the 
  inferior, 
  

   to 
  receive 
  the 
  proximal 
  end 
  of 
  the 
  humerus, 
  

   whose 
  condyle 
  is 
  adapted 
  to 
  it 
  both 
  in 
  size 
  and 
  

   shape. 
  It 
  is 
  a 
  flat 
  bone 
  curved 
  in 
  the 
  direction 
  

   of 
  its 
  plane, 
  which 
  is 
  vertical, 
  and 
  narrowed 
  

   distally, 
  where 
  it 
  is 
  broken 
  off. 
  It 
  is 
  expanded 
  

   proximally 
  into 
  two 
  heads 
  of 
  which 
  the 
  support 
  

   of 
  the 
  inferior 
  is 
  in 
  the 
  general 
  plane, 
  while 
  that 
  

   of 
  the 
  superior 
  is 
  obliquely 
  transverse 
  to 
  that 
  

   plane 
  : 
  this 
  head, 
  which 
  I 
  believe 
  to 
  be 
  the 
  

   anterior 
  and 
  attached 
  to 
  the 
  coracoid, 
  is 
  broken 
  

   off. 
  The 
  inferior 
  articular 
  face 
  is 
  slightly 
  con- 
  

   cave 
  ; 
  it 
  is 
  rugulose 
  for 
  an 
  articular 
  cartilage, 
  

   and 
  its 
  plane 
  is 
  exactly 
  transverse 
  to 
  the 
  long- 
  

   axis 
  of 
  the 
  bone. 
  Its 
  form 
  would 
  be 
  vertically 
  

   oval 
  but 
  for 
  an 
  expansion 
  on 
  what 
  I 
  suppose 
  to 
  

   be 
  the 
  outer 
  side. 
  The 
  inner 
  side 
  is 
  characterized 
  by 
  an 
  obtuse 
  longitudinal 
  ridge, 
  which 
  

   extends 
  upwards 
  and 
  backwards 
  from 
  the 
  anterior 
  head 
  and 
  soon 
  disappears. 
  A 
  simi- 
  

   lar 
  ridge 
  is 
  seen 
  in 
  the 
  ischium 
  of 
  Crocodilia. 
  As 
  this 
  ridge 
  disappears 
  from 
  the 
  inner 
  

   side, 
  a 
  more 
  obtuse 
  one 
  appears 
  on 
  the 
  outer, 
  and 
  is 
  in 
  line 
  with 
  the 
  subtransverse 
  expan- 
  

   sion 
  of 
  the 
  neck 
  of 
  the 
  anterior 
  head 
  ; 
  it 
  soon 
  reaches 
  the 
  posterior 
  margin 
  of 
  the 
  bone, 
  

   which 
  it 
  thickens. 
  Between 
  this 
  point 
  and 
  the 
  posterior 
  head, 
  the 
  margin 
  is 
  thin 
  and 
  

   acute. 
  A 
  more 
  imperfect 
  specimen 
  of 
  the 
  same 
  element 
  from 
  the 
  same 
  side 
  (the 
  right) 
  of 
  

   a 
  rather 
  smaller 
  individual 
  exhibits 
  similar 
  characters. 
  

  

  As 
  compared 
  - 
  with 
  the 
  scapula 
  of 
  Iguanodon, 
  Hylaeosaurus 
  and 
  Scelidosaurus, 
  a 
  strong 
  

   resemblance 
  is 
  seen 
  in 
  the 
  marked 
  distinction 
  of 
  the 
  outline 
  of 
  the 
  glenoid 
  cavity, 
  and 
  the 
  

   existence 
  of 
  a 
  large 
  distal 
  depression 
  of 
  a 
  subtriangular 
  form. 
  The 
  anterior 
  expansion 
  is 
  

   broken 
  away, 
  but 
  from 
  the 
  indications 
  at 
  the 
  fracture 
  was 
  probably 
  well 
  developed. 
  

  

  The 
  proportions 
  of 
  the 
  larger 
  scapula 
  indicate 
  a 
  gigantic 
  animal 
  fully 
  equal 
  to 
  the 
  

   known 
  Hadrosauri 
  ; 
  the 
  humeral 
  support 
  agrees 
  with' 
  that 
  bone 
  in 
  the 
  latter. 
  The 
  

  

  dimensions 
  are 
  as 
  follows: 
  — 
  

  

  In. 
  

  

  Length 
  of 
  fragment 
  on 
  posterior 
  margin, 
  13.9 
  

  

  Depth 
  proximally 
  (greatest), 
  7.2 
  

  

  " 
  distally, 
  4 
  

  

  