﻿REPTILE 
  FROM 
  AUSTRALIA 
  181 
  

  

  fourth 
  neural. 
  It 
  is 
  impressed 
  by 
  the 
  entering 
  angle 
  of 
  the 
  junc- 
  

   tion 
  of 
  the 
  second 
  costal 
  scute 
  (c 
  2) 
  with 
  the 
  second 
  and 
  third 
  verte- 
  

   bral 
  scutes 
  (v 
  2, 
  v 
  3). 
  The 
  length 
  of 
  the 
  rib-like 
  production 
  of 
  the 
  

   third 
  costal 
  scute 
  from 
  the 
  suture 
  with 
  the 
  second 
  costal 
  is 
  3 
  inches 
  

   10 
  lines 
  ; 
  the 
  entire 
  length 
  of 
  the 
  plate 
  is 
  6 
  inches 
  9 
  lines. 
  

  

  The 
  entire 
  extent 
  of 
  the 
  free 
  portion 
  of 
  the 
  fourth 
  costal 
  plate 
  

   (jol 
  4) 
  appears 
  to 
  be 
  preserved; 
  and 
  its 
  length 
  from 
  the 
  suture 
  with 
  

   the 
  third 
  costal 
  is 
  the 
  same 
  as 
  in 
  the 
  third 
  : 
  there 
  may 
  be 
  a 
  small 
  

   terminal 
  portion 
  wanting 
  in 
  both 
  ; 
  the 
  breadth 
  and 
  length 
  of 
  the 
  

   expanded 
  portion 
  seem 
  to 
  have 
  been 
  the 
  same 
  as 
  in 
  pi 
  3 
  ; 
  but 
  the 
  

   fracture 
  of 
  the 
  hind 
  part 
  of 
  the 
  specimen 
  may 
  have 
  removed 
  that 
  

   margin 
  of 
  the 
  fourth 
  costal. 
  

  

  This 
  plate 
  shows 
  the 
  impression 
  of 
  the 
  lateral 
  angle 
  of 
  the 
  third 
  

   vertebral 
  scute 
  (v 
  3) 
  at 
  its 
  junction 
  with 
  parts 
  of 
  the 
  second 
  and 
  

   third 
  costal 
  scutes 
  (c 
  2, 
  c 
  3). 
  

  

  Of 
  the 
  costal 
  plates 
  of 
  the 
  right 
  side, 
  parts 
  of 
  the 
  expanded 
  por- 
  

   tions 
  only 
  are 
  preserved 
  ; 
  and 
  they 
  have 
  been 
  partially 
  dislocated 
  

   from 
  the 
  vertebral 
  plates 
  by 
  pressure 
  from 
  above 
  ; 
  only 
  small 
  

   angular 
  portions 
  of 
  the 
  1st 
  and 
  4th 
  are 
  present. 
  

  

  Not 
  more 
  of 
  the 
  nuchal 
  plate 
  (ib. 
  ch) 
  is 
  preserved 
  than 
  serves 
  

   to 
  indicate 
  that 
  the 
  mesial 
  part 
  of 
  its 
  hind 
  border 
  is 
  slightly 
  pro- 
  

   duced 
  backward 
  to 
  unite 
  with 
  the 
  first 
  neural 
  plate 
  ; 
  the 
  rest 
  of 
  

   the 
  hind 
  border, 
  preserved 
  only 
  on 
  the 
  left 
  side, 
  unites 
  suturally 
  

   with 
  the 
  fore 
  border 
  of 
  the 
  expanded 
  part 
  of 
  the 
  first 
  costal 
  plate. 
  

   Laterally 
  the 
  nuchal 
  plate 
  unites 
  with 
  the 
  foremost 
  of 
  the 
  marginal 
  

   plates 
  (m 
  1) 
  ; 
  and 
  to 
  this 
  is 
  attached 
  a 
  portion 
  of 
  the 
  second 
  mar- 
  

   ginal 
  plate. 
  

  

  The 
  breadth 
  of 
  the 
  entire 
  carapace 
  of 
  Notochelys 
  costata, 
  taken 
  

   across 
  the 
  fourth 
  pair 
  of 
  the 
  costal 
  plates, 
  the 
  right 
  plate 
  being 
  

   restored, 
  is 
  14 
  inches. 
  Assuming 
  that 
  about 
  half 
  of 
  the 
  length 
  of 
  the 
  

   carapace 
  is 
  shown 
  in 
  the 
  fossil, 
  the 
  total 
  length 
  may 
  be 
  estimated 
  

   at 
  20 
  inches. 
  

  

  Of 
  the 
  plastron 
  are 
  preserved 
  the 
  right 
  hyo-hyposternals 
  (fig. 
  2, 
  

   p. 
  182, 
  Tips, 
  r) 
  and 
  a 
  great 
  proportion 
  of 
  the 
  left 
  (ib. 
  lips. 
  I). 
  They 
  

   appear 
  to 
  have 
  been 
  in 
  contact 
  mesially 
  for 
  rather 
  more 
  than 
  the 
  

   anterior 
  half 
  of 
  their 
  fore-and-aft 
  extent 
  : 
  the 
  postero-mesial 
  borders 
  

   diverge 
  at 
  almost 
  a 
  right 
  angle 
  from 
  the 
  mid 
  line. 
  The 
  best-preserved 
  

   hyo-hyposternal 
  rapidly 
  loses 
  in 
  length 
  as 
  it 
  extends 
  outwards 
  for 
  

   above 
  two 
  thirds 
  of 
  its 
  total 
  breadth 
  ; 
  then 
  it 
  again 
  expands 
  to 
  less 
  

   than 
  half 
  the 
  mesial 
  length, 
  and 
  terminates 
  in 
  diverging 
  pointed 
  

   rays, 
  of 
  which 
  the 
  hindmost 
  are 
  longest 
  and 
  narrowest 
  ; 
  two 
  of 
  

   these 
  are 
  bifurcate. 
  They 
  do 
  not 
  appear 
  to 
  have 
  effected 
  any 
  bony 
  

   union 
  with 
  the 
  costal 
  elements 
  of 
  the 
  carapace. 
  

  

  The 
  left 
  hyo-hyposternal 
  shows 
  the 
  best-preserved 
  mesial 
  border, 
  

   the 
  anterior 
  portion 
  of 
  which 
  seems 
  to 
  have 
  underlapped 
  the 
  corre- 
  

   sponding 
  border 
  of 
  the 
  right 
  bone. 
  The 
  underlapping 
  portion 
  shows 
  

   two 
  large 
  angular 
  processes, 
  each 
  an 
  inch 
  broad 
  at 
  the 
  base, 
  and 
  con- 
  

   tracting 
  to 
  a 
  point 
  ; 
  they 
  are 
  followed 
  by 
  a 
  series 
  of 
  six 
  or 
  seven 
  

   smaller 
  processes 
  diminishing 
  in 
  size 
  as 
  they 
  recede 
  in 
  position. 
  

  

  