﻿AND 
  AVES 
  OF 
  NORTH 
  AMERICA. 
  60-A 
  

  

  From 
  the 
  above, 
  four 
  points 
  may 
  be 
  derived: 
  1. 
  That 
  the 
  ribs 
  are 
  continued 
  to 
  the 
  sacrum 
  in 
  this 
  type, 
  a 
  char- 
  

   acter 
  not 
  before 
  pointed 
  out 
  among 
  its 
  representatives 
  in 
  this 
  country 
  or 
  Europe, 
  and 
  one 
  in 
  which 
  it 
  differs 
  from 
  the 
  

   Crocodilia 
  from 
  the 
  Cretaceous 
  to 
  the 
  present 
  period 
  inclusive. 
  2. 
  That 
  the 
  sacral 
  diapophyses 
  articulate 
  with 
  two 
  

   vertebrae 
  instead 
  of 
  one, 
  a 
  point 
  similarly 
  exceptional 
  with 
  the 
  last 
  point. 
  3d. 
  That 
  in 
  both 
  these 
  points 
  this 
  type 
  

   approaches 
  the 
  Dicynodontia 
  and 
  Dinosauria, 
  as 
  it 
  does 
  in 
  some 
  others. 
  4th. 
  That 
  the 
  B. 
  lepturus 
  belongs 
  to 
  a 
  dif- 
  

   ferent 
  species 
  from 
  that 
  from 
  N. 
  Carolina, 
  last 
  described, 
  in 
  having 
  at 
  least 
  three 
  diapophyses 
  with 
  double 
  articulation 
  

   near 
  the 
  extremity 
  instead 
  of 
  one, 
  and 
  to 
  a 
  different 
  genus 
  from 
  the 
  same, 
  because 
  several 
  of 
  these 
  are 
  cylindric 
  in 
  the 
  

   former, 
  and 
  broadly 
  flattened 
  in 
  the 
  latter. 
  

  

  Which 
  genus 
  is 
  distinct 
  from 
  Belodon 
  is 
  difficult 
  to 
  ascertain. 
  If 
  we 
  suppose 
  B. 
  carolinensis 
  to 
  represent 
  it, 
  as 
  it 
  

   certainly 
  does 
  in 
  cranial 
  characters 
  and 
  other 
  respects, 
  the 
  North 
  Carolina 
  specimen 
  will 
  represent 
  another 
  genus, 
  

   since 
  a 
  sacral 
  vertebra 
  of 
  B. 
  carolinensis 
  pi-esents 
  all 
  the 
  characters 
  of 
  that 
  of 
  B. 
  lepturus. 
  

  

  The 
  centra 
  of 
  the 
  vertebras 
  are 
  very 
  much 
  compressed, 
  and 
  the 
  articular 
  faces 
  flared 
  out 
  at 
  the 
  margins. 
  The 
  

   faces 
  are 
  wide 
  vertical 
  ovals 
  and 
  distinctly 
  concave. 
  The 
  posterior 
  face 
  of 
  the 
  supposed 
  last 
  dorsal 
  is 
  flattened, 
  and 
  

   presents 
  two 
  slightly 
  swollen 
  triangular 
  planes, 
  each 
  from 
  the 
  facet 
  of 
  the 
  margin. 
  

  

  The 
  neural 
  spines 
  of 
  the 
  anterior 
  vertebras 
  are 
  shorter 
  and 
  wider, 
  of 
  the 
  posterior 
  more 
  elevated 
  and 
  narrower. 
  

   The 
  rib 
  supporting 
  the 
  anterior 
  zygapophysis 
  is 
  very 
  prominent 
  in 
  all, 
  as 
  is 
  that 
  defining 
  the 
  margin 
  of 
  the 
  neural 
  

   arch. 
  They 
  include 
  a 
  short 
  vertical 
  concavity 
  between 
  them, 
  giving 
  the 
  vertebras 
  a 
  marked 
  character. 
  

  

  The 
  caudals 
  are 
  very 
  much 
  compressed, 
  more 
  so 
  than 
  in 
  B. 
  ? 
  priscus, 
  though 
  since 
  they 
  are 
  median 
  in 
  the 
  series, 
  

   and 
  those 
  of 
  the 
  latter 
  are 
  proximal, 
  there 
  would 
  probably 
  be 
  a 
  greater 
  resemblance 
  between 
  the 
  homologous 
  ones. 
  

   The 
  articular 
  extremities 
  are 
  vertically 
  oval, 
  and 
  but 
  little 
  flared 
  at 
  the 
  margins. 
  The 
  neural 
  arch 
  with 
  its 
  apophyses 
  

   is 
  compressed. 
  The 
  diapophyses 
  project 
  just 
  below 
  the 
  base 
  of 
  the 
  arch, 
  and 
  are 
  depressed 
  and 
  stout. 
  

  

  Measurements. 
  M. 
  

  

  Vertebra 
  1st 
  type, 
  0.18 
  

  

  Do. 
  height 
  neural 
  spine 
  from 
  canal, 
  0.10 
  

  

  Do. 
  length 
  diapophysis, 
  0.026 
  

  

  Do. 
  " 
  centrum, 
  0.05 
  

  

  Do. 
  diameter 
  centrum 
  middle, 
  0.021 
  

  

  Do. 
  " 
  " 
  articular 
  face, 
  0.055 
  

  

  Do. 
  " 
  " 
  vertical, 
  articular 
  face, 
  0.059 
  

  

  Total 
  elevation 
  type 
  2d, 
  0.1951 
  

  

  Do. 
  neural 
  spine 
  from 
  canal, 
  0.122 
  

  

  Do. 
  width 
  do., 
  0.04 
  

  

  Do. 
  length 
  centrum, 
  0.05 
  

  

  Do. 
  diameter 
  (transverse) 
  centrum 
  middle, 
  0.023 
  

  

  Do. 
  " 
  " 
  " 
  artic. 
  face, 
  0.054 
  

  

  Do. 
  " 
  vertical 
  " 
  " 
  0.06 
  

  

  Do. 
  elevation 
  type 
  3d, 
  0.186 
  

  

  Do. 
  neural 
  spine 
  from 
  canal, 
  0.11 
  

  

  Do. 
  length 
  centrum, 
  0.049 
  

  

  Do. 
  diam. 
  (transverse) 
  centrum 
  at 
  middle, 
  0.032 
  

  

  Do. 
  " 
  " 
  " 
  artic. 
  face, 
  0.061 
  

  

  Do. 
  " 
  vertical 
  " 
  " 
  0.062 
  

  

  Do. 
  expanse 
  anterior 
  zygapophyses, 
  0.07 
  

  

  Do. 
  diameter 
  neural 
  canal, 
  0.02 
  

  

  Length 
  diapophysis, 
  0.082 
  

   The 
  neural 
  canal 
  in 
  the 
  vertebra 
  first 
  described, 
  is 
  narrower 
  and 
  more 
  elevated 
  than 
  in 
  the 
  last 
  dorsal. 
  

   A 
  chevron 
  bone 
  has 
  nearly 
  cylindric 
  limbs 
  and 
  short 
  common 
  junction 
  of 
  the 
  same. 
  Their 
  proximal 
  extremities 
  

   are 
  considerably 
  expanded, 
  but 
  not 
  so 
  as 
  to 
  meet 
  on 
  the 
  median 
  line. 
  They 
  are 
  very 
  oblique 
  backwards 
  and 
  inwards. 
  

   Distal 
  extremity 
  strongly 
  striate. 
  

  

  