﻿AND 
  AVES 
  OF 
  NORTH 
  AMERICA. 
  219 
  

  

  adhering 
  to 
  the 
  matrix 
  on 
  the 
  body 
  of 
  the 
  same 
  vertebra. 
  That 
  of 
  the 
  seventh 
  is 
  wider 
  

   than 
  that 
  of 
  any 
  of 
  the 
  dorsals, 
  but 
  is 
  compressed 
  like 
  those 
  preceding. 
  The 
  length 
  of 
  

   the 
  shaft 
  is 
  nearly 
  equal 
  to 
  that 
  of 
  the 
  centra 
  of 
  the 
  6th, 
  7th, 
  and 
  8th 
  vertebrae, 
  the 
  two 
  

   being 
  proportioned 
  as 
  17 
  to 
  20. 
  

  

  The 
  heads 
  of 
  the 
  dorsals 
  are 
  a 
  slight 
  kidney-shaped 
  oval, 
  with 
  a 
  shallow 
  median 
  con- 
  

   cavity. 
  On 
  the 
  tenth 
  vertebra, 
  the 
  head 
  is 
  much 
  shortened 
  and 
  concave 
  medially, 
  on 
  the 
  

   posterior 
  face. 
  The 
  concavity 
  is 
  posterior 
  on 
  several 
  vertebrae 
  in 
  advance 
  of 
  this 
  point. 
  

   The 
  form 
  of 
  the 
  shaft 
  of 
  the 
  ribs 
  is 
  proximally, 
  broad 
  above, 
  and 
  narrowed 
  below, 
  i. 
  e., 
  

   concave 
  wedge-shaped 
  in 
  section. 
  The 
  superior 
  face 
  turns 
  over 
  to 
  the 
  posterior, 
  and 
  is 
  

   lost 
  in 
  it, 
  and 
  the 
  shaft 
  becomes 
  cylindric. 
  The 
  distal 
  extremities 
  of 
  the 
  seventh 
  cervical 
  

   and 
  of 
  two 
  of 
  the 
  dorsals, 
  the 
  only 
  ones 
  preserved, 
  are 
  deeply 
  concave 
  with 
  a 
  sharp 
  edge. 
  

  

  The 
  limbs 
  in 
  this 
  genus 
  are 
  of 
  remarkable 
  form. 
  Unfortunately, 
  no 
  metacarpals 
  or 
  

   phalanges 
  have 
  been 
  preserved. 
  There 
  are 
  the 
  remaining 
  bones 
  of 
  one 
  side 
  and 
  a 
  portion 
  

   of 
  those 
  of 
  the 
  other. 
  The 
  proximal 
  portion 
  of 
  the 
  left 
  scapular 
  and 
  both 
  coracoids 
  also 
  

   remain. 
  The 
  right 
  coracoid 
  is 
  crushed 
  and 
  adhering 
  closely 
  to 
  the 
  ninth, 
  tenth 
  and 
  

   eleventh 
  vertebrae, 
  its 
  glenoid 
  cavity 
  apparently 
  in 
  its 
  normal 
  position 
  opposite 
  the 
  middle 
  

   of 
  the 
  eleventh. 
  Thus 
  the 
  distance 
  of 
  the 
  limbs 
  from 
  the 
  head 
  is 
  apparently 
  ascertained. 
  

   The 
  external 
  margin 
  of 
  the 
  anterior 
  part 
  of 
  this 
  element 
  is 
  parallel 
  to 
  the 
  vertebral 
  axis 
  

   in 
  place 
  ; 
  the 
  posterior 
  corresponding 
  margin 
  much 
  incurved 
  and 
  thinned 
  out 
  to 
  an 
  acute 
  

   edge. 
  The 
  anterior 
  portion 
  is 
  more 
  prolonged 
  than 
  the 
  posterior, 
  while 
  the 
  inner 
  margin 
  

   forms 
  a 
  regular 
  curve 
  without 
  emarginations. 
  The 
  most 
  extensive 
  articular 
  margin 
  is 
  the 
  

   inner, 
  with 
  the 
  scapula; 
  it 
  is 
  suture-like, 
  corresponding 
  to 
  a 
  singularly 
  indented 
  margin 
  

   of 
  the 
  scapula. 
  Inside 
  of 
  its 
  anterior 
  margin 
  a 
  moderate 
  foramen 
  pierces 
  the 
  plate. 
  The 
  

   lower 
  articular 
  margin 
  is 
  lobed, 
  the 
  posterior 
  lobe 
  being 
  the 
  outline 
  of 
  the 
  glenoid 
  cavity. 
  

  

  The 
  greater 
  part 
  of 
  the 
  scapula 
  is 
  lost 
  ; 
  it 
  has 
  apparently 
  had 
  but 
  little 
  expanse 
  poste- 
  

   riorly, 
  where 
  the 
  margin 
  is 
  thick 
  and 
  little 
  curved. 
  The 
  anterior 
  part 
  of 
  the 
  plate 
  is 
  thin 
  

   and 
  much 
  produced, 
  I 
  suspect 
  into 
  a 
  pro-coracoid 
  or 
  acromial 
  process. 
  It 
  resembles 
  the 
  

   basis 
  of 
  Cuvier's 
  pubis 
  of 
  Mosasaurus, 
  which 
  bone 
  I 
  suppose 
  to 
  be 
  the 
  scapula 
  of 
  that 
  

   genus. 
  In 
  the 
  present 
  animal 
  the 
  anterior 
  margin 
  is 
  strongly 
  incurved 
  and 
  acute, 
  and 
  

   does 
  not 
  reach 
  the 
  articular 
  face, 
  but 
  bounds 
  a 
  rough 
  triangular 
  projection 
  in 
  front 
  of 
  it. 
  

   The 
  humerus 
  is 
  a 
  singular 
  bone, 
  and 
  unlike 
  that 
  of 
  any 
  other 
  animal; 
  it 
  approaches 
  

   nearest 
  that 
  of 
  Sphargis. 
  It 
  is 
  a 
  short, 
  wide, 
  flattened 
  bone, 
  distally 
  as 
  broad 
  as 
  long, 
  

   proximally 
  a 
  little 
  narrower, 
  contracted 
  medially, 
  with 
  such 
  prominent 
  muscular 
  insertions 
  

   as 
  to 
  give 
  it 
  four 
  process-like 
  angles 
  in 
  its 
  plane, 
  and 
  two 
  others 
  projecting 
  posteriorly 
  

   from 
  the 
  head. 
  The 
  articular 
  extremity 
  presents 
  an 
  elongate 
  oval 
  facet 
  for 
  the 
  ulna, 
  and 
  

   a 
  semi-discoid 
  one 
  for 
  the 
  radius. 
  The 
  radius 
  is, 
  in 
  accordance 
  with 
  this, 
  flat 
  anteriorly 
  

   and 
  convex 
  posteriorly 
  at 
  its 
  proximal 
  extremity; 
  its' 
  shaft 
  is 
  very 
  short, 
  and 
  the 
  distal 
  

  

  