﻿208 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  by 
  a 
  vertical 
  depression; 
  the 
  posterior, 
  or 
  that 
  meeting 
  the 
  odontoid 
  process, 
  is 
  quite 
  prominent 
  and 
  distinct. 
  The 
  

   anterior 
  facet 
  for 
  the 
  occipital 
  condyle, 
  is 
  transversely 
  divided 
  by 
  a 
  depression. 
  

  

  The 
  form 
  of 
  the 
  cervical 
  vertebra 
  is 
  so 
  much 
  like 
  that 
  of 
  the 
  Mosasaurus 
  dekayi 
  as 
  to 
  be 
  readily 
  taken 
  for 
  those 
  of 
  

   small 
  example 
  of 
  that 
  species. 
  The 
  first 
  dorsals, 
  or 
  those 
  without 
  hypapophysis, 
  are 
  more 
  elongate 
  than 
  in 
  the 
  latter, 
  

   and 
  the 
  body 
  is 
  more 
  cotracted, 
  so 
  that 
  the 
  ball 
  presents 
  a 
  projecting 
  rim 
  all 
  round. 
  This 
  is 
  readily 
  knocked 
  off 
  in 
  

   the 
  rough 
  handling 
  the 
  specimens 
  usually 
  receive. 
  The 
  cup 
  is 
  also 
  proportionately 
  expanded. 
  Posterior 
  dorsals 
  

   where 
  the 
  diapophyses 
  issue 
  half 
  from 
  the 
  centrum, 
  have 
  the 
  latter 
  slightly 
  depressed; 
  where 
  the 
  diapophysis 
  comes 
  

   three-fourths 
  from 
  the 
  body, 
  the 
  articular 
  faces 
  are 
  a 
  broad 
  transverse 
  ovate, 
  well 
  expanded 
  on 
  the 
  margins, 
  below 
  

   which 
  the 
  surface 
  is 
  slightly 
  striate. 
  In 
  the 
  longer 
  or 
  anterior 
  dorsals, 
  the 
  rudiment 
  of 
  zygosphen 
  and 
  zygantrum 
  

   is 
  well 
  marked. 
  

  

  Unfortunately, 
  no 
  caudal 
  vertebra 
  of 
  this 
  species 
  have 
  been 
  preserved, 
  so 
  that 
  I 
  do 
  not 
  know 
  their 
  form. 
  The 
  

   posterior 
  dorsals 
  are 
  so 
  much 
  more 
  depressed 
  than 
  in 
  Liodon 
  la^vis, 
  that 
  future 
  discovery 
  may 
  justify 
  the 
  generic 
  sep- 
  

   aration 
  of 
  the 
  genus 
  Nectoportheus, 
  which 
  I 
  originally 
  applied 
  to 
  this 
  animal. 
  

  

  For 
  the 
  largest 
  measurements, 
  I 
  refer 
  to 
  Dr. 
  Leidy's 
  essay 
  on 
  Cretaceous 
  Reptiles, 
  where 
  the 
  description 
  of 
  the 
  

   large 
  specimens 
  of 
  Macrosaurus 
  la^vis 
  belong 
  to 
  the 
  present 
  species. 
  

  

  The 
  following 
  are 
  the 
  proportions 
  of 
  the 
  smaller 
  and 
  typical 
  individual, 
  from 
  L. 
  T. 
  Germain: 
  

  

  Indies. 
  Lines. 
  

  

  Length 
  centrum 
  cervical, 
  (with 
  ball) 
  34 
  

  

  Depth 
  ball 
  of 
  same, 
  18.5 
  

  

  Width 
  " 
  " 
  21 
  

  

  Length 
  anterior 
  dorsal, 
  34 
  

  

  "Width 
  cup, 
  24 
  

  

  Proximal 
  width 
  outer 
  face 
  quadratum, 
  28 
  

  

  Length 
  quadratum 
  to 
  lower 
  edge 
  pit, 
  20 
  

  

  " 
  opisthotic, 
  (see 
  description) 
  3 
  4 
  

  

  " 
  outer 
  margin 
  do., 
  3 
  4 
  

  

  This 
  was 
  a 
  large 
  and 
  powerful 
  reptile, 
  and 
  probably 
  more 
  elongate 
  in 
  proportion 
  to 
  its 
  bulk 
  than 
  the 
  Mosasauri, 
  

   well 
  deserving 
  the 
  name 
  Macrosaurus 
  which 
  Owen 
  has 
  applied 
  to 
  an 
  ally. 
  

   From 
  the 
  upper 
  Green 
  Sand 
  Bed 
  of 
  the 
  New 
  Jersey 
  Cretaceous. 
  

  

  BAPTOSAURUS, 
  Marsh. 
  

  

  Proceed. 
  Acad. 
  Nat. 
  Sci., 
  Phila., 
  January, 
  1870. 
  Halisaurus, 
  Marsh, 
  Sill. 
  Am. 
  Jour. 
  Sci. 
  Arts, 
  1869, 
  395, 
  nee 
  

   Johnsonii, 
  1866. 
  

  

  A 
  genus 
  known 
  chiefly 
  from 
  vertebrae. 
  These 
  resemble 
  those 
  of 
  Liodon, 
  more 
  par- 
  

   ticularly 
  such 
  species 
  as 
  L. 
  validus, 
  but 
  present 
  marked 
  differences 
  in 
  the 
  cervical 
  part 
  of 
  

   the 
  series. 
  Here 
  the 
  hypapophyses 
  are 
  compressed 
  and 
  elongate, 
  and 
  rugose 
  at 
  the 
  ex- 
  

   tremity 
  for 
  the 
  insertion 
  of 
  muscles, 
  instead 
  of 
  being 
  truncated 
  by 
  an 
  articular 
  face 
  to 
  

   which 
  a 
  separate 
  bone 
  is 
  united, 
  as 
  occurs 
  in 
  all 
  the 
  other 
  genera 
  of 
  Pythonomorpha 
  here 
  

   enumerated. 
  In 
  this 
  it 
  moa-e 
  nearly 
  resembles 
  the 
  ordinary 
  types 
  of 
  Lacertilia 
  and 
  

   Ophidia. 
  There 
  is 
  no 
  indication 
  of 
  zygosphen 
  in 
  the 
  two 
  species 
  described. 
  The 
  neural 
  

   spine 
  is 
  elevated, 
  compressed, 
  and 
  narrow. 
  The 
  dorsals 
  are 
  of 
  an 
  even 
  more 
  elongate 
  

   character 
  than 
  in 
  Liodon. 
  The 
  species 
  known 
  have 
  the 
  articular 
  faces 
  depressed 
  or 
  

   transverse 
  oval. 
  This 
  character 
  is 
  not 
  necessarily 
  of 
  generic 
  value, 
  and 
  hence 
  I 
  attach 
  

   less 
  importance 
  to 
  it 
  than 
  does 
  Marsh 
  in 
  his 
  diagnosis. 
  

  

  