﻿2 
  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  of 
  them 
  was, 
  however, 
  published 
  in 
  the 
  Proceedings 
  of 
  the 
  Academy 
  for 
  the 
  same 
  year, 
  

   page 
  234. 
  

  

  Additional 
  material 
  was 
  shortly 
  afterwards 
  sent 
  to 
  the 
  writer, 
  and 
  the 
  important 
  con- 
  

   tributions 
  on 
  the 
  Batrachia 
  of 
  the 
  coal 
  measures, 
  and 
  on 
  the 
  Elasmosauridge, 
  written. 
  

   The 
  Palaeophis 
  and 
  some 
  of 
  the 
  Testudinata 
  and 
  Pythonomorpha 
  were 
  also 
  added. 
  

  

  In 
  the 
  course 
  of 
  these 
  investigations, 
  prosecuted 
  during 
  the 
  past 
  six 
  years, 
  with 
  

   reference 
  to 
  the 
  structure 
  and 
  relations 
  of 
  the 
  extinct 
  Peptilia, 
  the 
  following 
  general 
  con- 
  

   clusions 
  have 
  been 
  attained 
  to, 
  besides 
  many 
  of 
  lesser 
  significance. 
  

  

  First 
  : 
  That 
  the 
  Dinosauria 
  present 
  a 
  graduated 
  series 
  of 
  approximations 
  to 
  the 
  birds, 
  

   and 
  possess 
  some 
  peculiarities 
  in 
  common 
  with 
  that 
  class, 
  standing 
  between 
  it 
  and 
  the 
  

   Crocodilia. 
  

  

  Second 
  : 
  That 
  serpents 
  exist 
  in 
  the 
  Eocene 
  formations 
  of 
  this 
  Country. 
  

  

  Third 
  : 
  That 
  the 
  Chelydra 
  type 
  was 
  greatly 
  developed 
  during 
  the 
  American 
  Cretaceous, 
  

   and 
  that 
  all 
  the 
  supposed 
  marine 
  turtles 
  described 
  from 
  it, 
  are 
  really 
  of 
  the 
  first 
  named 
  

   group. 
  

  

  Fourth 
  : 
  That 
  the 
  Reptilia 
  of 
  the 
  American 
  Triassic 
  are 
  of 
  the 
  Beloclon 
  type. 
  

  

  Fifth 
  : 
  The 
  discovery 
  of 
  the 
  characters 
  of 
  the 
  order 
  Pythonomorpha. 
  

  

  Sixth 
  The 
  development 
  of 
  the 
  characters 
  of 
  numerous 
  members 
  of 
  the 
  Batrachian 
  

   Sub-order 
  Microsauria 
  in 
  the 
  United 
  States. 
  

  

  I 
  must 
  express 
  my 
  obligations 
  to 
  Prof. 
  Geo. 
  H. 
  Cook, 
  of 
  the 
  Geological 
  Survey 
  of 
  

   New 
  Jersey, 
  who 
  kindly 
  placed 
  the 
  specimens 
  procured 
  during 
  the 
  Survey 
  at 
  my 
  disposal. 
  

   I 
  am 
  also 
  particularly 
  indebted 
  to 
  Prof. 
  John 
  S. 
  Newberry, 
  of 
  Columbia 
  College, 
  New 
  

   York, 
  and 
  director 
  of 
  the 
  Geological 
  Survey 
  of 
  Ohio, 
  for 
  the 
  loan 
  of 
  the 
  unique 
  and 
  

   important 
  material 
  from 
  the 
  carboniferous 
  beds 
  at 
  Linton, 
  Ohio, 
  contained 
  in 
  his 
  private 
  

   collection. 
  I 
  am 
  under 
  similar 
  obligations 
  to 
  Wm. 
  R. 
  Webb, 
  Superintendent 
  of 
  the 
  Land 
  

   Office 
  at 
  Topeka, 
  Kansas, 
  for 
  the 
  important 
  type 
  specimens 
  of 
  Polycotylus 
  latipinnis, 
  

   and 
  to 
  Prof. 
  Agassiz, 
  for 
  the 
  freedom 
  of 
  study 
  and 
  description 
  of 
  the 
  unequalled 
  Mosa- 
  

   sauroid 
  material 
  in 
  the 
  Museum 
  of 
  Comparative 
  Zoology, 
  Cambridge. 
  Also 
  to 
  Philip 
  P. 
  

   Tyson, 
  of 
  Baltimore, 
  for 
  similar 
  advantages, 
  and 
  to 
  Dr. 
  Th^ophilus 
  M. 
  Turner, 
  of 
  Fort 
  

   Wallace, 
  Kansas, 
  for 
  the 
  discovery 
  of 
  that 
  extraordinary 
  reptile, 
  the 
  Elasmosarus 
  pla- 
  

   tyurus, 
  and 
  its 
  shipment 
  in 
  unusually 
  good 
  condition. 
  Dr. 
  E. 
  11. 
  Showalter. 
  of 
  Uniontown, 
  

   Alabama, 
  has 
  placed 
  me 
  under 
  obligation, 
  in 
  sending 
  the 
  beautiful 
  fossil 
  of 
  Clidastes 
  

   propython. 
  I 
  must 
  also 
  express 
  obligations 
  to 
  Prof 
  Marsh, 
  of 
  Yale 
  College, 
  Dr. 
  Lock- 
  

   wood, 
  of 
  Keyport, 
  New 
  Jersey, 
  and 
  to 
  other 
  friends. 
  

  

  