﻿Tn. 
  

  

  Lin. 
  

  

  2 
  

  

  1.5 
  

  

  1 
  

  

  

  

  7 
  

  

  2 
  

  

  4.5 
  

  

  1 
  

  

  9 
  

  

  

  9 
  

  

  1 
  

  

  9 
  

  

  1 
  

  

  

  5 
  

  

  

  1 
  

  

  11 
  

  

  

  2.5 
  

  

  144 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  The 
  vascular 
  grooves 
  are 
  quite 
  distinct, 
  forming 
  short, 
  straight 
  and 
  zigzag, 
  sometimes 
  crossing 
  grooves. 
  In 
  the 
  

   posterior 
  or 
  wider 
  marginals, 
  the 
  upper 
  inner 
  margin 
  is 
  produced 
  inwards 
  above 
  the 
  lower. 
  The 
  rib 
  pits 
  are 
  round. 
  

   None 
  of 
  the 
  marginal 
  bones 
  have 
  recurved 
  edges. 
  

  

  Measurements. 
  

   Width 
  of 
  a 
  posterior 
  marginal, 
  

   Depth 
  " 
  " 
  " 
  within, 
  

  

  Depth 
  " 
  an 
  anterior 
  " 
  at 
  edge, 
  

  

  Length 
  " 
  " 
  

   Width 
  " 
  " 
  " 
  

  

  Width 
  of 
  dermal 
  scute 
  on 
  same, 
  

   Width 
  of 
  middle 
  marginal, 
  above 
  

   "Width 
  " 
  " 
  below 
  

  

  Length 
  of 
  costal 
  bone 
  on 
  curve, 
  

   Width 
  " 
  " 
  " 
  

  

  Thickness 
  of 
  costal 
  bone 
  at 
  middle 
  margin, 
  

  

  The 
  specimens 
  on 
  which 
  this 
  species 
  are 
  based 
  were 
  obtained 
  from 
  the 
  pits 
  of 
  the 
  West 
  Jersey 
  .Marl 
  Company, 
  

   near 
  Barnesboro, 
  Gloucester 
  county, 
  New 
  Jersey, 
  and 
  were 
  presented 
  to 
  the 
  author 
  by 
  I. 
  C. 
  Yoorhees, 
  Superin- 
  

   tendent 
  there. 
  

  

  LYTOLOMA, 
  Cope. 
  

  

  This 
  genus 
  is 
  more 
  like 
  Chelone 
  than 
  any 
  of 
  the 
  Chelydrine 
  forms 
  here 
  described. 
  

   The 
  characters 
  are 
  derived 
  solely 
  from 
  portions 
  of 
  the 
  carapace 
  which 
  are 
  preserved, 
  and 
  

   are 
  as 
  follows 
  : 
  

  

  The 
  marginal 
  bones 
  free 
  from 
  the 
  carapace 
  except 
  at 
  the 
  anterior 
  and 
  posterior 
  por- 
  

   tions, 
  narrow 
  anteriorly, 
  expanded 
  behind. 
  

  

  The 
  evidence 
  for 
  these 
  characters 
  consists 
  : 
  first, 
  of 
  a 
  median 
  and 
  a 
  first 
  marginal 
  bone 
  

   of 
  a 
  species 
  from 
  the 
  green 
  sand 
  of 
  Barnesboro 
  ; 
  second, 
  of 
  two 
  marginals 
  and 
  a 
  mandi- 
  

   bular 
  arch 
  from 
  Birmingham 
  ; 
  third, 
  of 
  four 
  consecutive 
  posterior 
  marginals 
  from 
  Mullica 
  

   Hill; 
  fourth, 
  of 
  parts 
  of 
  a 
  skeleton 
  from 
  Hornerstown. 
  The 
  first 
  represents 
  the 
  Chelo- 
  

   nioid 
  freedom 
  of 
  all 
  but 
  the 
  nuchal 
  marginal 
  plate, 
  in 
  front, 
  by 
  the 
  entirety 
  of 
  the 
  margins 
  of 
  

   the 
  first. 
  The 
  second 
  presents 
  a 
  free 
  anterior 
  marginal, 
  and 
  a 
  narrow 
  middle 
  marginal 
  

   with 
  rib 
  pit. 
  The 
  third 
  probably 
  belonged 
  to 
  the 
  same 
  species 
  as 
  the 
  last, 
  and 
  presents 
  

   in 
  the 
  inner 
  margins 
  an 
  absence 
  of 
  the 
  disposition 
  to 
  expansion, 
  which 
  exists 
  in 
  the 
  genus 
  

   Osteopygis, 
  where 
  the 
  union 
  of 
  disc 
  and 
  marginals 
  is 
  extensive. 
  It 
  appears 
  to 
  have 
  been 
  

   similar 
  to 
  the 
  genus 
  Propleura 
  in 
  the 
  posterior 
  part 
  of 
  the 
  carapace. 
  

  

  Two 
  species 
  of 
  the 
  genus 
  appear 
  to 
  be 
  indicated 
  by 
  the 
  material 
  at 
  my 
  disposal, 
  which 
  

   can 
  be 
  thus 
  distinguished. 
  

  

  The 
  anterior 
  (first 
  and 
  probably 
  second) 
  marginals 
  with 
  entire 
  convex 
  margin. 
  

  

  L. 
  JEANESII. 
  

  

  The 
  anterior 
  (second 
  and 
  probably 
  first) 
  marginals 
  with 
  openly 
  emarginate 
  margin. 
  

  

  P. 
  ANGUSTA. 
  

  

  