﻿82 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  Lines. 
  

   Width 
  of 
  palate, 
  18.5 
  

  

  Height 
  of 
  os 
  maxillare 
  at 
  middle, 
  14. 
  

  

  Thickness 
  of 
  palatine 
  suture 
  of 
  o. 
  maxillare, 
  2.5 
  

  

  Cretaceous 
  Green 
  Sand 
  of 
  New 
  Jersey. 
  

  

  HYPOSAURUS 
  ERATERCTTLUS, 
  Cope. 
  

   Spec. 
  nov. 
  

  

  This 
  small 
  species 
  seems 
  to 
  he 
  clearly 
  indicated 
  hy 
  a 
  portion 
  of 
  the 
  ramus 
  mandihuli 
  containing 
  three 
  and 
  half 
  a 
  

   fourth 
  alveoli, 
  and 
  two 
  perfect 
  teeth. 
  These 
  parts 
  are 
  less 
  than 
  half 
  the 
  size 
  of 
  those 
  of 
  the 
  smaller 
  individual 
  of 
  H. 
  

   rogersi, 
  whose 
  maxillary 
  hone 
  and 
  teeth 
  are 
  described 
  in 
  the 
  preceding 
  article. 
  The 
  crowns 
  of 
  the 
  teeth 
  are 
  shorter 
  

   and 
  more 
  compressed 
  than 
  those 
  in 
  the 
  corresponding 
  part 
  of 
  the 
  jaws 
  in 
  H. 
  rogersi 
  ; 
  they 
  are 
  marked 
  witli 
  a 
  coarse 
  

   obtuse 
  fluting 
  to 
  near 
  the 
  tip, 
  with 
  a 
  finely 
  striate 
  enamel 
  as 
  in 
  Holops 
  glyptodon 
  ; 
  in 
  those 
  of 
  H. 
  rogersi, 
  the 
  enamel 
  

   is 
  smooth 
  and 
  ridged 
  by 
  fine 
  keels, 
  which 
  do 
  not 
  extend 
  more 
  than 
  half 
  the 
  length 
  of 
  the 
  crown. 
  

  

  That 
  the 
  animal 
  of 
  which 
  I 
  describe 
  this 
  fragment 
  was 
  not 
  the 
  young 
  of 
  the 
  larger 
  Hyposaurus, 
  is, 
  I 
  think, 
  

   indicated 
  by 
  the 
  deep 
  grooving 
  and 
  strong 
  ridging 
  of 
  the 
  dense 
  layer 
  of 
  bone 
  of 
  the 
  ramus 
  ; 
  by 
  the 
  minute 
  pulp 
  

   cavity 
  of 
  the 
  crowns 
  of 
  the 
  teeth, 
  and 
  by 
  the 
  well 
  developed 
  successional 
  tooth 
  in 
  the 
  fang 
  of 
  one 
  of 
  the 
  latter, 
  whose 
  

   apex 
  has 
  nearly 
  reached 
  the 
  alveolar 
  margin. 
  That 
  the 
  individual 
  is 
  not 
  fully 
  grown 
  is 
  probable, 
  but 
  that 
  it 
  is 
  of 
  

   smaller 
  species 
  than 
  the 
  H. 
  rogersi, 
  there 
  appears 
  to 
  be 
  little 
  room 
  for 
  doubt. 
  

  

  The 
  ramus 
  is 
  scarcely 
  flattened 
  below, 
  as 
  is 
  the 
  case 
  with 
  most 
  gavials, 
  and 
  the 
  depth 
  at 
  the 
  symphysis 
  is 
  equal 
  

   the 
  width 
  of 
  each 
  ramus. 
  Sculpture 
  in 
  deep 
  longitudinal 
  grooves 
  slightly 
  inosculating. 
  Teeth 
  directed 
  very 
  little 
  

   outwards 
  : 
  their 
  fangs 
  and 
  crowns 
  are 
  considerably 
  compressed 
  ; 
  the 
  antero-posterior 
  cutting 
  edge 
  is 
  stronger 
  than 
  

   the 
  ridges, 
  and 
  does 
  not 
  diminish 
  to 
  the 
  base 
  of 
  the 
  crown. 
  Viewed 
  from 
  within 
  the 
  form 
  is 
  symmetrical 
  and 
  

   straight 
  ; 
  from 
  behind 
  their 
  crown 
  is 
  greatly 
  incurved. 
  The 
  outline 
  of 
  the 
  crown 
  from 
  within 
  is 
  an 
  isosceles 
  triangle, 
  

   the 
  width, 
  more 
  than 
  .66 
  the 
  height. 
  Ribs 
  on 
  the 
  inner 
  face, 
  seven, 
  on 
  the 
  outer, 
  eight. 
  A 
  few 
  teeth 
  in 
  the 
  jaws 
  

   of 
  H. 
  rogersi 
  are 
  as 
  short 
  and 
  broad 
  as 
  those 
  here 
  described, 
  but 
  they 
  are 
  not 
  found 
  in 
  the 
  middle 
  of 
  the 
  series 
  as 
  in 
  

   this 
  species, 
  but 
  probably 
  belong 
  in 
  the 
  posterior 
  alveoli, 
  as 
  occurs 
  in 
  some 
  alligators. 
  

  

  Length 
  of 
  fragment, 
  

  

  Width 
  at 
  middle, 
  

  

  No. 
  of 
  alveolae 
  in 
  an 
  inch 
  : 
  three 
  and 
  half 
  and 
  interspace. 
  

  

  Length 
  tooth 
  above 
  alveolus, 
  

  

  " 
  crown 
  of 
  tooth, 
  

   Width 
  " 
  " 
  at 
  base, 
  

  

  From 
  the 
  middle 
  Green 
  sand 
  bed 
  at 
  Birmingham, 
  Burlington, 
  Co., 
  N. 
  J. 
  Presented 
  to 
  the 
  Academy 
  by 
  Judson 
  

   C. 
  Gaskill. 
  

  

  LNCERTAE 
  SEDIS. 
  

  

  The 
  following 
  species 
  probably 
  belongs 
  to 
  the 
  Amphicoeli, 
  but 
  to 
  what 
  genus 
  cannot 
  well 
  be 
  determined, 
  as 
  

   nothing 
  but 
  the 
  teeth 
  are 
  known. 
  

  

  CROCODILUS 
  HUMILIS, 
  Leidy. 
  

  

  Lines. 
  

  

  19.3 
  

  

  6. 
  

  

  4. 
  

  

  2.75 
  

  

  1.75 
  

  

  Trans. 
  Amer., 
  Phil., 
  1860, 
  p. 
  146. 
  Tab. 
  

   Bad 
  Lands 
  of 
  the 
  Judith 
  River, 
  Nebraska. 
  

  

  