﻿AND 
  AYES 
  OF 
  NORTH 
  AMERICA. 
  127 
  

  

  bone 
  is 
  everywhere 
  remarkable 
  for 
  the 
  thickness 
  of 
  its 
  dense 
  layer, 
  and 
  the 
  closeness 
  of 
  the 
  texture 
  of 
  the 
  spongy. 
  

   The 
  former 
  is 
  one-third 
  the 
  thickness 
  of 
  the 
  sternal 
  and 
  costal 
  bones 
  fractured. 
  

  

  The 
  scute 
  sutures 
  of 
  the 
  inferior 
  surface 
  are 
  obsolete; 
  those 
  of 
  the 
  dorsal 
  surface 
  are 
  like 
  those 
  of 
  Adocus; 
  i. 
  e., 
  

   the 
  vertebrals 
  with 
  bracket-shaped 
  lateral 
  borders 
  with 
  the 
  costal 
  proceeding 
  from 
  the 
  point 
  of 
  the 
  bracket. 
  

  

  The 
  marginal 
  bones 
  vary 
  much 
  in 
  thickness 
  proximally; 
  they 
  have 
  two 
  proximal 
  sutures, 
  one 
  side 
  convex, 
  

   the 
  other 
  concave. 
  Four 
  have 
  a 
  heavy 
  border, 
  round 
  in 
  section; 
  in 
  two 
  of 
  these 
  it 
  is 
  considerably 
  everted: 
  another 
  

   has 
  a 
  rather 
  thin 
  margin, 
  slightly 
  decurved, 
  with 
  a 
  submarginal 
  groove 
  separating 
  it 
  from 
  the 
  most 
  massive 
  portion 
  

   The 
  costal 
  bones 
  are 
  strongly 
  convex 
  in 
  their 
  length, 
  indicating 
  an 
  arched 
  carapace. 
  

  

  Measurements. 
  

   Hyosternal 
  width, 
  

  

  " 
  " 
  to 
  origin 
  axillary 
  abutment, 
  

  

  " 
  length 
  on 
  median 
  suture, 
  

   " 
  thickness 
  near 
  mesosternal 
  line, 
  

  

  " 
  " 
  " 
  hyposternal 
  " 
  

  

  Hyposternal 
  thickness 
  near 
  poster, 
  suture, 
  

   Costal, 
  width, 
  

  

  " 
  thickness 
  vertebral 
  suture, 
  

   Marginal 
  No. 
  1 
  width, 
  

   " 
  length, 
  

   " 
  " 
  proximal 
  thickness, 
  

  

  " 
  No. 
  5 
  " 
  " 
  

  

  " 
  " 
  length, 
  

  

  " 
  width, 
  

   " 
  " 
  width 
  dermal 
  scute, 
  

  

  This 
  animal 
  is 
  therefore 
  a 
  species 
  of 
  considerable 
  size, 
  though 
  less 
  than 
  most 
  of 
  those 
  described 
  here, 
  and 
  par- 
  

   ticularly 
  convex 
  and 
  solid 
  in 
  every 
  part. 
  While 
  the 
  sutural 
  lines 
  of 
  the 
  hyosternal 
  measure 
  about 
  the 
  same 
  as 
  in 
  E. 
  

   firmus 
  (Emys 
  Leidy), 
  it 
  is 
  much 
  more 
  convex 
  and 
  not 
  so 
  thick 
  at 
  the 
  mesosternal 
  suture. 
  The 
  marginal 
  bones 
  are 
  

   relatively 
  just 
  half 
  the 
  size. 
  The 
  Pleurosternum 
  pec 
  tor 
  ale, 
  differs 
  in 
  being 
  very 
  much 
  flatter, 
  and 
  in 
  having 
  a 
  

   more 
  discoid 
  mesosternal 
  bone. 
  The 
  hyosternals 
  are 
  also 
  much 
  thicker 
  at 
  their 
  union 
  with 
  the 
  marginals, 
  than 
  the 
  

   present 
  is. 
  

  

  A 
  portion 
  of 
  a 
  hyo-or 
  hyposternal 
  bone 
  collected 
  at 
  the 
  same 
  place, 
  and 
  near 
  or 
  at 
  the 
  same 
  time, 
  maybe 
  referred 
  

   to 
  a 
  larger 
  individual 
  of 
  the 
  same 
  species 
  or 
  to 
  E. 
  firmus. 
  It 
  exhibits 
  a 
  wedge 
  for 
  a 
  diagonal 
  gomphosis, 
  between 
  

   the 
  two 
  sutures, 
  which 
  are 
  preserved. 
  The 
  thickness 
  on 
  the 
  median 
  suture 
  is 
  14 
  lines. 
  

  

  The 
  density 
  of 
  the 
  sternal 
  bones 
  is 
  in 
  marked 
  contrast 
  to 
  that 
  of 
  the 
  E. 
  crassus 
  

   according 
  to 
  Owen, 
  where 
  the 
  structure 
  is 
  remarkably 
  spongy 
  and 
  open. 
  

  

  EMYS 
  TURGIDUS, 
  Cope. 
  

  

  This 
  species 
  is 
  represented 
  by 
  two 
  individuals 
  in 
  a 
  more 
  or 
  less 
  fragmentary 
  condition 
  

   in 
  the 
  private 
  collection 
  of 
  Dr. 
  Samuel 
  Lockwood, 
  of 
  Keyport, 
  N. 
  J. 
  One 
  of 
  these, 
  

   selected 
  for 
  description, 
  embraces 
  proximal 
  portions 
  of 
  four 
  left 
  costal 
  bones 
  and 
  of 
  three 
  

   right 
  ones, 
  with 
  a 
  vertebral, 
  other 
  fragments 
  of 
  costals, 
  four 
  marginals 
  (one 
  from 
  the 
  

   bridge), 
  the 
  greater 
  part 
  of 
  both 
  hyosternals 
  and 
  the 
  mesosternum. 
  

  

  These 
  indicate 
  a 
  species 
  of 
  about 
  half 
  the 
  bulk 
  of 
  the 
  E. 
  petrosus, 
  and 
  differing 
  in 
  

   many 
  particulars. 
  These 
  are 
  especially 
  the 
  relatively 
  much 
  wider 
  and 
  flatter, 
  hyostcr- 
  

  

  n. 
  

  

  Lin. 
  

  

  3 
  

  

  9. 
  

  

  2 
  

  

  1.5 
  

  

  2 
  

  

  1.0 
  

  

  

  9. 
  

  

  

  7.2 
  

  

  

  9. 
  

  

  1 
  

  

  7.5 
  

  

  

  8. 
  

  

  2 
  

  

  1.5 
  

  

  1 
  

  

  7. 
  

  

  

  3. 
  

  

  

  8.2 
  

  

  1 
  

  

  6. 
  

  

  1 
  

  

  7.5 
  

  

  

  9. 
  

  

  