﻿124 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  STYLEMYS 
  NEBRACENSIS, 
  Leidy. 
  

  

  Stylemys 
  nebracensis, 
  Emys 
  hemisplierica 
  and 
  E. 
  oweni. 
  Pr. 
  A. 
  N. 
  Sci., 
  Phila., 
  1851, 
  p, 
  172. 
  

   Testudo 
  nebracensis, 
  Leidy, 
  Ancient 
  Fauna 
  Nebraska, 
  103. 
  T. 
  hemisphcerica, 
  T. 
  oweni 
  et 
  T. 
  lata, 
  Leidy 
  1. 
  c. 
  

   Tabs, 
  xix, 
  xx, 
  xxi, 
  xxiii, 
  xxiv. 
  

  

  Miocene 
  Tertiary 
  of 
  Nebraska. 
  

  

  A 
  specimen 
  of 
  this 
  species 
  presented 
  to 
  the 
  Academy 
  of 
  Natural 
  Sciences 
  by 
  Dr. 
  

   Hay 
  den 
  measures 
  20 
  inches 
  in 
  length, 
  and 
  1 
  5 
  inches 
  in 
  width. 
  

  

  STYLEMYS 
  CULBERTSONII, 
  Leidy. 
  

   Testudo 
  culbertsonii, 
  Leidy, 
  Ancient 
  Fauna 
  of 
  Nebraska, 
  Tab. 
  xxii. 
  

  

  Miocene 
  Tertiary 
  of 
  Nebraska. 
  

  

  STYLEMYS 
  NIOBRARENSIS, 
  Leidy. 
  

   Testudo 
  (St.) 
  niobrarensis,, 
  Leidy, 
  Proceed. 
  Ac. 
  Nat. 
  Sci., 
  Phil., 
  1858, 
  29. 
  

  

  Pliocene 
  of 
  the 
  Niobrara 
  river, 
  Nebraska. 
  

  

  COMPSEMYS, 
  Leidy. 
  

   Proc. 
  Ac. 
  N. 
  Sci., 
  1856, 
  312. 
  

  

  The 
  remains 
  of 
  this 
  genus 
  do 
  not 
  offer 
  any 
  very 
  marked 
  features 
  to 
  distinguish 
  them 
  

   from 
  Emys. 
  The 
  existence 
  of 
  generic 
  distinction 
  is 
  however 
  suggested 
  by 
  the 
  delicate 
  

   areolate 
  sculpture 
  of 
  the 
  surface 
  of 
  the 
  carapace. 
  Costal 
  capitula 
  well 
  developed 
  ; 
  verte- 
  

   bral 
  scuta 
  subquadrate. 
  

  

  COMPSEMYS 
  OBSCURUS. 
  

  

  Emys 
  obscurus, 
  Leidy, 
  Pr. 
  A, 
  N. 
  Sci., 
  1856, 
  312. 
  

  

  From 
  the 
  Upper 
  Jurassic 
  of 
  Long 
  lake, 
  Nebraska. 
  

  

  « 
  COMPSEMYS 
  VICTUS, 
  Leidy 
  I. 
  c. 
  

  

  Upper 
  Jurassic 
  Bad 
  Lands, 
  Judith 
  River, 
  Nebraska. 
  

  

  CISTUDO, 
  Flem. 
  

   CISTUDO 
  EURYPYGIA, 
  Cope. 
  

  

  This 
  extinct 
  species 
  is 
  represented 
  by 
  a 
  portion 
  of 
  the 
  posterior 
  margin 
  of 
  the 
  carapace, 
  which 
  includes 
  more 
  

   or 
  less 
  of 
  four 
  marginal, 
  two 
  vertebral, 
  and 
  one 
  costal, 
  scuta. 
  The 
  relations 
  of 
  the 
  osseous 
  elements 
  are 
  much 
  as 
  

   in 
  C. 
  clausa; 
  i. 
  e., 
  the 
  posterior 
  costals 
  are 
  united 
  on 
  the 
  median 
  line, 
  without 
  rudimental 
  vertebral 
  below, 
  and 
  the 
  

   last 
  vertebral 
  is 
  an 
  irregular 
  pentagon 
  with 
  the 
  two 
  anterior 
  sides 
  elongate. 
  There 
  are 
  traces 
  of 
  angular 
  concentric 
  

   sculpture 
  as 
  in 
  the 
  existing 
  species, 
  which 
  encloses 
  a 
  slightly 
  angular 
  boss 
  on 
  the 
  posterior 
  margin 
  of 
  the 
  costal 
  

   scutum. 
  

  

  What 
  distinguishes 
  this 
  box-tortoise 
  from 
  the 
  existing 
  one, 
  is 
  the 
  greater 
  width 
  of 
  the 
  vertebral 
  scuta, 
  and 
  the 
  

   different 
  form 
  of 
  the 
  marginals. 
  The 
  costal 
  suture 
  of 
  the 
  vertebral, 
  instead 
  of 
  joining 
  a 
  prolongation 
  of 
  the 
  penul- 
  

  

  