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  THE 
  EXTINCT 
  BATRACHIA, 
  REPTILIA 
  

  

  Incertae 
  sedis. 
  

  

  PIRATOSATJRUS, 
  Leidy. 
  

  

  PIRATOSAURUS 
  PLICATUS. 
  Leidy. 
  

  

  Cretaceous 
  Rept. 
  N. 
  Am., 
  29, 
  30, 
  Tab. 
  

  

  Cretaceous 
  of 
  Red 
  River 
  Settlement, 
  Lat. 
  49 
  deg., 
  Northern 
  Minnesota. 
  Described 
  from 
  a 
  tooth. 
  

  

  THECODONTTIA. 
  

   Owen 
  in 
  part. 
  

  

  In 
  this 
  suborder 
  we 
  have 
  a 
  singularly 
  generalized 
  group, 
  combining 
  characters 
  of 
  

   lizards, 
  crocodiles 
  and 
  Sauropterygians. 
  The 
  neural 
  arch 
  of 
  the 
  vertebrae 
  united 
  by 
  suture 
  

   and 
  the 
  slightly 
  biconcave 
  centrum, 
  resemble 
  the 
  last 
  two, 
  so 
  also 
  the 
  abdominal 
  ribs. 
  

   The 
  limbs 
  are 
  rather 
  crocodilian, 
  the 
  position 
  of 
  the 
  nares, 
  Plesiosaurian. 
  The 
  clavicle 
  is 
  

   lacertian, 
  while 
  the 
  three 
  vertebrae 
  of 
  the 
  sacrum 
  and 
  the 
  femur 
  are 
  between 
  these 
  and 
  

   the 
  Dinosauria. 
  

  

  The 
  most 
  important 
  characters 
  distinguishing 
  these 
  animals 
  from 
  the 
  Sauropterygia 
  

   are 
  the 
  presence 
  of 
  an 
  elongate 
  sacrum 
  and 
  the 
  more 
  ambulatory 
  form 
  of 
  limbs. 
  

  

  Our 
  knowledge 
  of 
  the 
  order 
  is 
  almost 
  confined 
  to 
  Belodon 
  Meyer, 
  and 
  is 
  derived 
  from 
  

   that 
  author's 
  descriptions 
  of 
  those 
  large 
  and 
  remarkable 
  reptiles 
  derived 
  from 
  the 
  Keuper 
  

   of 
  Wiirtemburg, 
  the 
  Belodon 
  kapfii 
  Meyer, 
  B. 
  plieningeri 
  Miinst., 
  and 
  B. 
  planirostris 
  

   Meyer. 
  

  

  The 
  American 
  species 
  of 
  the 
  order 
  are 
  known 
  only 
  from 
  the 
  valuable 
  collections 
  made 
  

   by 
  Wheatley 
  at 
  Phcenixville, 
  Pa., 
  and 
  by 
  Emmons 
  at 
  Deep 
  River, 
  in 
  Chatham 
  county, 
  

   in 
  North 
  Carolina. 
  The 
  former 
  are 
  in 
  my 
  hands 
  for 
  examination 
  and 
  description, 
  and 
  

   will 
  be 
  the 
  subject 
  of 
  an 
  appendix 
  to 
  this 
  work. 
  

  

  BELODON, 
  Meyer. 
  

  

  Although 
  this 
  genus 
  does 
  not 
  present 
  the 
  swimming 
  extremities 
  of 
  Plesiosaurus 
  and 
  

   Nothosaurus, 
  its 
  structure 
  in 
  this 
  respect 
  is 
  not 
  much 
  more 
  different 
  from 
  them, 
  than 
  

   that 
  of 
  the 
  marine 
  turtles 
  is 
  from 
  the 
  terrestial 
  families 
  of 
  the 
  same 
  order. 
  The 
  

   structure 
  of 
  the 
  sphenoidal 
  region, 
  the 
  peculiar 
  position 
  of 
  the 
  external 
  nostrils, 
  almost 
  

   above 
  the 
  orbits, 
  with 
  the 
  rhizodont 
  dentition, 
  are 
  points 
  in 
  which 
  they 
  agree. 
  The 
  

   position 
  of 
  the 
  exterior 
  nares 
  cannot 
  be 
  regarded 
  as 
  an 
  ordinal 
  character, 
  since 
  we 
  see 
  

   what 
  remarkable 
  differences 
  of 
  position 
  it 
  exhibits 
  in 
  the 
  existing 
  family 
  Varanidae. 
  

   There 
  is 
  is 
  every 
  probability 
  that 
  these 
  animals 
  were 
  aquatic. 
  The 
  posterior 
  position 
  of 
  

   the 
  nostrils, 
  like 
  that 
  in 
  many 
  other 
  marine 
  animals, 
  enabled 
  them 
  to 
  plunge 
  the 
  long 
  

   muzzle 
  beneath 
  the 
  surface 
  of 
  the 
  water 
  or 
  mud 
  without 
  interfering 
  with 
  respiration. 
  

  

  The 
  dentition 
  of 
  the 
  posterior 
  parts 
  of 
  the 
  mouth 
  has 
  been 
  shown 
  by 
  Von 
  Meyer 
  to 
  

   be 
  quite 
  different 
  from 
  that 
  of 
  the 
  anterior 
  regions; 
  the 
  latter 
  are 
  prehensile, 
  that 
  is 
  

   elongate 
  conic, 
  the 
  former 
  cutting, 
  i. 
  e., 
  flattened, 
  broader 
  and 
  with 
  trenchant 
  edges. 
  

  

  