﻿AND 
  AYES 
  OF 
  NORTH 
  AMERICA. 
  99 
  

  

  As 
  Leidy 
  has 
  referred 
  the 
  eastern 
  and 
  western 
  herbivorous 
  Dinosouria 
  to 
  one 
  on 
  the 
  same 
  genus, 
  and 
  as 
  there 
  is 
  

   much 
  doubt 
  as 
  to 
  whether 
  the 
  present 
  animal 
  is 
  not 
  one 
  of 
  them, 
  I 
  refer 
  the 
  latter 
  here 
  as 
  an 
  expression 
  of 
  the 
  

   probabilities 
  of 
  the 
  case. 
  

  

  PALAEOSCINCUS, 
  Leidy. 
  

  

  This 
  herbivorous 
  genus 
  is, 
  as 
  remarked 
  by 
  its 
  describer, 
  an 
  interesting 
  representative 
  of 
  the 
  Hylaeosaurus 
  of 
  the 
  

   European 
  Wealden. 
  

  

  PALAEOSCINCUS 
  COSTATUS, 
  Leidy. 
  

  

  Tr. 
  Am. 
  Phil. 
  Soc, 
  18G0, 
  145. 
  

  

  Upper 
  Jurassic 
  Bad 
  Lands 
  of 
  Judith 
  River, 
  Nebraska. 
  

  

  ASTRODON, 
  Johnston. 
  

   Amer. 
  Journ. 
  Dent. 
  Sci., 
  1859. 
  

  

  ASTRODON 
  JOHNSTONI, 
  Leidy. 
  

  

  Cret. 
  Eept. 
  U. 
  S., 
  102, 
  Tab. 
  

  

  Cretaceous 
  greensand, 
  Maryland, 
  (near 
  Bladensburg.) 
  

  

  To 
  a 
  genus 
  nearly 
  allied 
  to 
  the 
  present, 
  should 
  be 
  referred 
  the 
  animal 
  represented 
  by 
  

   a 
  large 
  tooth 
  discovered 
  by 
  Thomas 
  Wright 
  in 
  the 
  Island 
  of 
  "Wight, 
  described 
  and 
  fig- 
  

   ured 
  by 
  him 
  in 
  the 
  Annals 
  and 
  Magazine 
  Nat. 
  History, 
  1852, 
  p. 
  89. 
  The 
  creature 
  has 
  

   been 
  of 
  larger 
  size 
  than 
  the 
  Astrodon 
  Jolinston% 
  and 
  apparently 
  of 
  a 
  formidable 
  nature. 
  

  

  GONIOPODA, 
  Cope. 
  

  

  Proceed. 
  Ac. 
  N. 
  Sci., 
  Phila., 
  1S66, 
  317. 
  

   Harpagmo&uuria 
  Haeckel, 
  I860. 
  

  

  Proximal 
  tarsal 
  bones 
  distinct 
  from 
  tibia 
  ; 
  the 
  latter 
  closely 
  embraced 
  by 
  the 
  much 
  

   enlarged 
  astragalus, 
  on 
  its 
  inferior 
  and 
  anterior 
  faces, 
  forming 
  an 
  immoveable 
  articulation. 
  

   Astragalus, 
  with 
  an 
  extensive 
  anterior 
  articular 
  condyle 
  below, 
  above 
  in 
  contact 
  with 
  the 
  

   fibula, 
  which 
  is 
  much 
  reduced, 
  especially 
  distally. 
  Anterior 
  part 
  of 
  the 
  ilium 
  dilated, 
  and 
  

   plate-like. 
  

  

  This 
  group 
  is 
  named 
  from 
  the 
  abrupt 
  flexure 
  of 
  the 
  ankle 
  in 
  the 
  middle 
  of 
  the 
  

   tarsus, 
  preventing 
  the 
  foot 
  from 
  being 
  extended 
  in 
  line 
  with 
  the 
  leg. 
  

  

  It 
  represents 
  no 
  doubt 
  an 
  early 
  stage 
  of 
  developement 
  of 
  the 
  Symphypoda, 
  and 
  is 
  

   remarkably 
  similar 
  in 
  the 
  same 
  points 
  in 
  the 
  structure 
  of 
  the 
  posterior 
  extremity, 
  to 
  the 
  

   embryo 
  of 
  the 
  chick 
  at 
  about 
  the 
  ninth 
  day. 
  At 
  that 
  time 
  the 
  metatarsals 
  of 
  the 
  bird 
  are 
  

   distinct, 
  proximally 
  joined 
  by 
  a 
  single 
  tarsal 
  element, 
  which 
  itself 
  is 
  separated 
  by 
  the 
  artic- 
  

   ulation 
  from 
  a 
  transverse 
  piece 
  composed 
  of 
  the 
  confluent 
  proximal 
  tarsal 
  series. 
  The 
  

   latter 
  element 
  is 
  not 
  at 
  this 
  time 
  united 
  with 
  the 
  tibia, 
  but 
  it 
  is 
  in 
  contact 
  with 
  the 
  fibula. 
  

  

  