﻿Classification 
  of 
  the 
  Order 
  Iniomi. 
  

   Family 
  2. 
  Omosudida?. 
  

  

  131 
  

  

  The 
  genus 
  Omosudis, 
  Giinther, 
  agrees 
  with 
  the 
  Seopel- 
  

   archidae 
  in 
  its 
  moderately 
  elongate 
  form 
  and 
  short 
  dorsal 
  fin 
  

   but 
  it 
  has 
  the 
  head, 
  mouth, 
  and 
  teeth 
  of 
  the 
  Alepidosauridaa. 
  

   It 
  differs 
  from 
  both 
  in 
  the 
  pectoral 
  arch, 
  for 
  the 
  cleithrum 
  is 
  

   not 
  expanded 
  and 
  the 
  postcleithra 
  are 
  long 
  and 
  slender 
  and 
  

   reach 
  the 
  ventral 
  profile. 
  

  

  Family 
  3. 
  Alepidosauridae. 
  

  

  Body 
  very 
  long, 
  strongly 
  compressed, 
  naked. 
  Snout 
  pro- 
  

   duced, 
  pointed 
  ; 
  maxillary 
  with 
  a 
  large 
  triangular 
  laminar 
  

   expansion 
  anteriorly; 
  no 
  supramaxillary 
  ; 
  teeth 
  compressed 
  ; 
  

   lower 
  jaw 
  with 
  one 
  or 
  a 
  pair 
  of 
  canines 
  on 
  each 
  side. 
  Skull 
  

   triangular 
  in 
  form 
  when 
  seen 
  from 
  above, 
  gradually 
  increasing 
  

   in 
  width 
  backwards 
  ; 
  interorbital 
  region 
  flat, 
  moderately 
  

   broad 
  ; 
  parietals 
  separated 
  by 
  the 
  supraoccipital 
  ; 
  posterior 
  

  

  Fig;. 
  6. 
  

  

  <7e/> 
  

  

  Alepidosaurus 
  ferox 
  ; 
  lateral 
  view 
  of 
  skeleton 
  of 
  head 
  and 
  pectoral 
  arch. 
  

   Lettering 
  as 
  in 
  figures 
  2 
  and 
  5. 
  

  

  temporal 
  fossa? 
  not 
  roofed 
  ; 
  lateral 
  ethmoids 
  meeting 
  in 
  the 
  

   middle 
  line; 
  suborbitals 
  not 
  ossified. 
  Postcleithra 
  laminar; 
  

   cleithrum 
  much 
  expanded, 
  triangular 
  or 
  triradiate 
  in 
  form. 
  

   51 
  vertebra? 
  ; 
  centra 
  long, 
  without 
  transverse 
  processes 
  ; 
  ribs 
  

   slender, 
  sessile. 
  Dorsal 
  fin 
  very 
  long, 
  of 
  simple 
  non-articu- 
  

   lated 
  rays. 
  

  

  The 
  skeletal 
  characters 
  given 
  are 
  those 
  of 
  an 
  example 
  of 
  

   Alepidosaurus 
  ferox. 
  

  

  The 
  Cretaceous 
  Apateodus 
  is 
  known 
  from 
  the 
  skull, 
  

   jaws, 
  and 
  teeth, 
  which 
  seem 
  to 
  be 
  very 
  similar 
  to 
  those 
  of 
  

   Alepidosaurus 
  and 
  Omosudis. 
  

  

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