﻿42 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  with 
  powerful 
  propelling 
  flippers. 
  The 
  preceding 
  cut 
  illustrates 
  its 
  form 
  and 
  size 
  in 
  rela- 
  

   tion 
  to 
  the 
  posterior 
  dorsals 
  from 
  nearly 
  the 
  same 
  position 
  in 
  the 
  C. 
  magnus 
  and 
  Elasmo- 
  

   saurus 
  platyurus. 
  

  

  The 
  general 
  characters 
  of 
  the 
  cervical 
  and 
  dorsal 
  series 
  are 
  very 
  similar 
  to 
  those 
  of 
  

   Elasmosaurus, 
  but 
  they 
  all 
  exhibit 
  considerably 
  larger 
  neural 
  canals. 
  In 
  the 
  immature 
  

   individual, 
  the 
  neural 
  arch 
  of 
  the 
  dorsal 
  vertebra? 
  is 
  not 
  coossified, 
  but 
  is 
  separated 
  by 
  

   suture 
  as 
  in 
  Plesiosaurus. 
  

  

  That 
  there 
  are 
  several 
  species 
  of 
  this 
  genus 
  is 
  suggested 
  by 
  Leidy, 
  and 
  seems 
  probable 
  

   to 
  the 
  writer. 
  As 
  one 
  of 
  these 
  has 
  been 
  already 
  named, 
  the 
  characters 
  of 
  those 
  which 
  

   appear 
  distinct 
  may 
  be 
  pointed 
  out. 
  

  

  Anterior 
  caudals, 
  articular 
  faces 
  with 
  rounded 
  margins 
  ; 
  antero-posterior 
  diameter 
  

   greater, 
  2 
  in., 
  width, 
  2 
  in. 
  7 
  1. 
  Pit 
  of 
  diapophysis 
  1 
  in. 
  3 
  1. 
  

  

  c. 
  VETUSTUS. 
  

  

  Anterior 
  caudals, 
  articular 
  faces 
  with 
  acute 
  marginal 
  angle, 
  antero-posteriorly 
  shorter 
  

   1 
  in. 
  7 
  1. 
  by 
  2 
  in. 
  6 
  1. 
  in 
  width 
  ; 
  pit 
  1 
  1 
  1. 
  Cervical 
  with 
  straight 
  sides 
  and 
  broader 
  form 
  ; 
  

   width 
  31.2 
  1. 
  by 
  24.5 
  long, 
  the 
  ^diapophysis 
  narrow 
  and 
  stout. 
  

  

  c. 
  MAGNUS. 
  

  

  Anterior 
  dorsals 
  shorter 
  and 
  higher 
  than 
  in 
  C. 
  magnus, 
  the 
  posterior 
  ceivicals, 
  there- 
  

   fore 
  shorter 
  than 
  in 
  the 
  same 
  ; 
  diapophysis 
  of 
  first 
  dorsal 
  longer. 
  

  

  C. 
  GRANDIS. 
  

  

  Posterior 
  cervical 
  with 
  neural 
  canal 
  as 
  large 
  as 
  C. 
  magnus, 
  but 
  centrum 
  four 
  times 
  as 
  

   large, 
  and 
  a 
  strong 
  longitudinal 
  ridge 
  half 
  way 
  between 
  pleurapophysis 
  and 
  neural 
  arch, 
  

   giving 
  pentagonal 
  section 
  : 
  45 
  1. 
  long 
  by 
  52 
  1. 
  wide 
  ; 
  hence 
  longer. 
  

  

  E. 
  ORIENTALIS. 
  

  

  CIMOLIASAURUS 
  VETUSTUS, 
  Leidy. 
  

  

  Discosaurus 
  Leidy, 
  Proc. 
  Acad. 
  N. 
  Sci., 
  1851, 
  326. 
  Cretaceous 
  Reptiles, 
  N. 
  A., 
  22. 
  Plesiosaurus, 
  DeKay 
  Ann. 
  

   Lye, 
  N. 
  Y., 
  1828, 
  165, 
  Tab. 
  

  

  If 
  the 
  vertebrae 
  from 
  Alabama 
  from 
  Jos. 
  Jones, 
  described 
  by 
  Leidy 
  in 
  the 
  Cretaceous 
  

   Reptiles 
  as 
  No. 
  1, 
  are 
  typical 
  of 
  this 
  species, 
  they 
  present 
  certain 
  peculiarities 
  which 
  distin- 
  

   guish 
  them 
  from 
  those 
  of 
  an 
  individual 
  of 
  C. 
  magnus 
  which 
  I 
  describe 
  below 
  ; 
  perhaps 
  

   the 
  species 
  are 
  distinct. 
  

  

  Cretaceous 
  Alabama, 
  ? 
  Mississippi 
  and 
  ? 
  New 
  Jersey. 
  

  

  