﻿40 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  articular 
  face 
  is 
  a 
  transverse 
  oval. 
  The 
  size 
  of 
  the 
  animal 
  is 
  similar 
  to 
  that 
  of 
  the 
  Plesiosauri 
  of 
  medium 
  dimensions, 
  

   perhaps 
  ten 
  feet 
  in 
  length, 
  admitting 
  elongate 
  neck 
  and 
  tail, 
  of 
  which 
  there 
  is 
  no 
  evidence. 
  

  

  Position. 
  — 
  Bed 
  Q. 
  Hayden's 
  Section 
  of 
  Great 
  Lignite 
  hasin 
  of 
  Nebraska. 
  (Trans. 
  Am. 
  Philos. 
  Soc, 
  1860,135.) 
  

   perhaps 
  of 
  the 
  Cretaceous 
  age; 
  from 
  the 
  Moreau 
  River. 
  

  

  PLESIOSAURUS, 
  Conyb. 
  . 
  

   I 
  refer 
  the 
  following 
  species 
  to 
  this 
  genus 
  provisionally, 
  and 
  with 
  doubt. 
  

  

  PLESIOSAURUS 
  LOCKWOODII, 
  Cope. 
  

  

  This 
  reptile 
  is 
  represented 
  by 
  but 
  few 
  remains, 
  which 
  are 
  in 
  the 
  private 
  collection 
  of 
  Dr. 
  Samuel 
  Lockwood, 
  of 
  

   Monmouth 
  County, 
  N. 
  J. 
  A 
  single 
  dorsal 
  vertebra, 
  which 
  he 
  kindly 
  lent 
  me 
  for 
  description, 
  presents 
  characters 
  which 
  

   are 
  so 
  marked 
  when 
  compared 
  with 
  other 
  marine 
  Sauria 
  as 
  to 
  require 
  notice. 
  

  

  The 
  centrum 
  is 
  of 
  the 
  general 
  form 
  of 
  Plesiosaurus 
  and 
  Cimoliasaurus, 
  and 
  the 
  arch 
  has 
  a 
  sutural 
  attachment 
  as 
  

   in 
  the 
  former. 
  The 
  suture 
  is 
  the 
  surface 
  of 
  a 
  sub-round 
  pit, 
  almost 
  like 
  that 
  of 
  Ichthyosaurus, 
  and 
  not 
  like 
  that 
  

   typical 
  of 
  Plesiosaurus, 
  or 
  the 
  young 
  of 
  Cimaliosaurus 
  magnus. 
  In 
  the 
  latter 
  the 
  suture 
  is 
  an 
  oval 
  concavity 
  which 
  

   extends 
  throughout 
  the 
  length 
  of 
  the 
  centrum. 
  The 
  pit 
  in 
  this 
  species 
  measures 
  little 
  more 
  than 
  one-third 
  the 
  

   length 
  of 
  the 
  centrum. 
  The 
  floor 
  of 
  the 
  neural 
  canal 
  is 
  quite 
  fiat. 
  The 
  sides 
  of 
  the 
  centrum 
  are 
  strongly 
  and 
  

   regularly 
  concave, 
  rather 
  less 
  strongly 
  below 
  than 
  laterally. 
  The 
  margins 
  flare 
  regularly, 
  and 
  are 
  not 
  striate 
  

   grooved 
  or 
  ribbed 
  as 
  in 
  many 
  species. 
  There 
  is 
  a 
  strong 
  venous 
  foramen 
  a 
  short 
  distance 
  below 
  the 
  neural 
  arch 
  and 
  

   two 
  medially 
  below. 
  

  

  The 
  sj^ecies 
  is 
  further 
  characterized 
  by 
  the 
  regularly 
  concave 
  articular 
  faces, 
  without 
  median 
  plane 
  or 
  prominent 
  

   portion, 
  as 
  in 
  Cimoliosaurus 
  species. 
  They 
  are 
  more 
  concave 
  than 
  those 
  of 
  the 
  Elasmosauri 
  also. 
  The 
  form 
  of 
  the 
  

   surface 
  is 
  entirely 
  circular. 
  

  

  Width 
  articular 
  surface, 
  

   Depth 
  " 
  

   Width 
  pit 
  neural 
  arch, 
  

   Length 
  centrum, 
  

  

  This 
  species 
  I 
  have 
  dedicated 
  to 
  its 
  discoverer, 
  Dr. 
  Lockwood, 
  who 
  has 
  contributed 
  in 
  various 
  ways 
  to 
  the 
  

   progress 
  of 
  Natural 
  Science. 
  

  

  It 
  is 
  the 
  earliest 
  sea 
  saurian 
  from 
  this 
  country, 
  as 
  it 
  was 
  derived 
  from 
  the 
  clays 
  which 
  underlie 
  the 
  lower 
  green 
  

   sand 
  bed. 
  It 
  was 
  dug 
  from 
  a 
  brick 
  clay 
  pit 
  near 
  Matteawan, 
  Monmouth 
  County, 
  N. 
  J. 
  

  

  CIMOLIASAURUS, 
  Leidy. 
  

   Cimoliasaurus 
  and 
  Discosaurus, 
  Leidy. 
  Proceed. 
  Academy 
  Nat. 
  ScL, 
  Phila., 
  1851, 
  325 
  — 
  1854, 
  72, 
  tab. 
  ii, 
  figs. 
  4, 
  5, 
  

   C, 
  and 
  1851, 
  32G; 
  Cretaceous 
  Reptiles, 
  22 
  and 
  25, 
  tabs. 
  IV., 
  V., 
  VI. 
  Brimosaiwus 
  Leidy, 
  Pr. 
  A. 
  N. 
  Sci., 
  Phila., 
  1855, 
  472. 
  

  

  This 
  genus 
  has 
  been 
  chiefly 
  illustrated 
  by 
  Leidy, 
  who 
  has 
  described 
  remains 
  of 
  its 
  

   species 
  from 
  the 
  cretaceous 
  deposits 
  of 
  many 
  of 
  the 
  States 
  east 
  of 
  the 
  Mississippi. 
  It 
  has 
  

   remained 
  for 
  the 
  discovery 
  of 
  Elasmosaurus 
  to 
  prove 
  that 
  the 
  two 
  supposed 
  genera 
  named 
  

   by 
  Leidy, 
  are 
  really 
  one, 
  his 
  supposed 
  caudals 
  of 
  Discosaurm* 
  being 
  really 
  caudals 
  of 
  Cim- 
  

  

  * 
  This 
  genus 
  was 
  originally 
  proposed 
  on 
  two 
  vertebrae 
  from 
  Georgia, 
  and 
  a 
  vertebra 
  from 
  New 
  Jersey 
  described 
  

   by 
  Dekay. 
  He 
  afterwards 
  added 
  vertebrae 
  from 
  Alabama, 
  Mississippi 
  and 
  New 
  Jersey. 
  Some 
  of 
  these 
  were 
  regarded 
  

   as 
  cervicals; 
  they 
  are, 
  however, 
  anterior 
  caudals. 
  As 
  Leidy 
  observes, 
  there 
  are 
  several 
  species 
  among 
  them, 
  and 
  it 
  

   may 
  be, 
  several 
  genera, 
  but 
  as 
  the 
  genera 
  cannot 
  be 
  distinguished 
  by 
  the 
  caudal 
  vertebra), 
  it 
  appears 
  to 
  me 
  that 
  Dis- 
  

   cosaurus 
  cannot 
  be 
  preserved. 
  While 
  distinguishing 
  the 
  genus 
  from 
  Cimoliasaurus, 
  Leidy 
  adds, 
  "The 
  supposed 
  cau- 
  

   dals 
  of 
  Discosaurus 
  I 
  have 
  suspected 
  to 
  be 
  anterior 
  cervicals, 
  notwithstanding 
  the 
  apparent 
  provision 
  for 
  the 
  articula- 
  

   tion 
  of 
  chevron 
  bones. 
  If 
  all 
  the 
  vertebra; 
  be 
  viewed 
  as 
  belonging 
  to 
  one 
  animal, 
  they 
  represent 
  cervicals, 
  dorsals 
  and 
  

   lumbars 
  of 
  Discosaurus; 
  otherwise 
  they 
  represent 
  a 
  cervical 
  and 
  caudals 
  of 
  the 
  latter, 
  and 
  dorsals 
  and 
  lnmbars 
  of 
  Cim- 
  

   oliasaurus.'" 
  In 
  case 
  of 
  their 
  identity, 
  it 
  may 
  be 
  observed, 
  Leidy 
  refers 
  them 
  all 
  to 
  Discosaurus. 
  Cimoliasaurus 
  was, 
  

   however, 
  proposed 
  first. 
  

  

  2 
  

  

  Lin. 
  

  

  8 
  

  

  2 
  

  

  7.8 
  

  

  

  8.4 
  

  

  1 
  

  

  11.6 
  

  

  