﻿Mr. 
  R. 
  Lydekker 
  on 
  new 
  Fossil 
  Chelonia. 
  53 
  

  

  a 
  central 
  black 
  hour-glassed 
  shaped 
  fascia 
  somewhat 
  margined 
  

   and 
  streaked 
  with 
  ochraceous, 
  the 
  posterior 
  margin 
  also 
  

   ochraceous 
  ; 
  mesonotum 
  with 
  two 
  longitudinal 
  waved 
  linear 
  

   fascia?, 
  between 
  which 
  near 
  anterior 
  margin 
  are 
  two 
  oblique 
  

   spots, 
  and 
  the 
  cruciform 
  elevation 
  ochraceous 
  ; 
  abdominal 
  

   segmental 
  margins 
  ochraceous 
  ; 
  apices 
  of 
  the 
  femora 
  luteous, 
  

   anterior 
  and 
  posterior 
  tibia? 
  annulated 
  at 
  base, 
  intermediate 
  

   tibia? 
  both 
  at 
  base 
  and 
  apex 
  with 
  fuscous. 
  

  

  Tegmina 
  pale 
  greenish 
  ochraceous-hyaline, 
  the 
  venation 
  

   brownish 
  ochraceous 
  ; 
  a 
  large 
  pale 
  fuscous 
  spot 
  at 
  bases 
  of 
  

   second, 
  third, 
  fourth, 
  fifth, 
  and 
  seventh 
  apical 
  areas, 
  some 
  

   small 
  spots 
  at 
  bases 
  of 
  sixth 
  and 
  eighth 
  apical 
  areas, 
  two 
  very 
  

   small 
  spots 
  on 
  the 
  margins 
  of 
  third 
  ulnar 
  area, 
  and 
  a 
  series 
  of 
  

   large 
  marginal 
  spots 
  at 
  the 
  apices 
  of 
  the 
  longitudinal 
  veins 
  to 
  

   apical 
  areas. 
  Wings 
  pale 
  hyaline, 
  the 
  venation 
  brownish 
  

   ochraceous. 
  

  

  Long. 
  excl. 
  tegm., 
  <$ 
  34 
  millim., 
  exp. 
  tegm. 
  75 
  millim. 
  

  

  Hah. 
  Sumatra 
  (Leyden 
  Mus.). 
  

  

  VII. 
  — 
  Preliminary 
  Notice 
  of 
  new 
  Fossil 
  Chelonia. 
  

   By 
  R. 
  Lydekker, 
  B.A., 
  F.G-.S. 
  

  

  Aulacochelys, 
  gen. 
  nov. 
  

  

  I 
  propose 
  this 
  name 
  for 
  Trionyx 
  circumsulcatics, 
  Owen, 
  

   from 
  the 
  Upper 
  Eocene 
  (Lower 
  Oligocene) 
  of 
  Hordwell, 
  which 
  

   differs 
  from 
  all 
  species 
  of 
  Trionyx 
  by 
  the 
  presence 
  of 
  a 
  deep 
  

   groove 
  in 
  the 
  free 
  border 
  of 
  the 
  costals. 
  

  

  Trachyasjn's 
  cegyptiacus, 
  sp. 
  nov. 
  

  

  This 
  species 
  is 
  based 
  on 
  a 
  nearly 
  entire 
  carapace 
  in 
  the 
  

   Natural-History 
  Museum 
  (no. 
  R. 
  229) 
  which 
  was 
  obtained 
  

   during 
  the 
  excavation 
  of 
  the 
  Suez 
  Canal 
  from 
  beds 
  of 
  

   unknown, 
  but 
  probably 
  Tertiary, 
  age. 
  It 
  is 
  distinguished 
  

   from 
  the 
  typical 
  T. 
  Lardyi, 
  Meyer, 
  of 
  the 
  Swiss 
  Miocene, 
  by 
  

   the 
  much 
  narrower 
  neural 
  shields. 
  

  

  Trachyaspis 
  has 
  been 
  hitherto 
  known 
  only 
  by 
  detached 
  

   fragments 
  of 
  the 
  carapace, 
  and 
  has 
  been 
  regarded 
  as 
  allied 
  to 
  

   Trionyx 
  or 
  Tretosternum. 
  That 
  it 
  has 
  nothing 
  to 
  do 
  with 
  

   the 
  former 
  is 
  evident 
  from 
  the 
  presence 
  of 
  epidermal 
  shields 
  ; 
  

   and 
  I 
  am 
  inclined 
  to 
  think 
  from 
  the 
  evidence 
  of 
  the 
  nuchal 
  

   region 
  of 
  the 
  present 
  specimen 
  that 
  it 
  is 
  equally 
  removed 
  

   from 
  the 
  latter, 
  of 
  which 
  the 
  affinities 
  arc 
  with 
  the 
  Chely- 
  

   drida?. 
  The 
  nature 
  of 
  the 
  sculpture 
  of 
  the 
  carapace 
  is 
  an 
  

  

  