﻿CHELONIA 
  AND 
  A 
  TOOTH 
  OF 
  (?) 
  OENITHOPSIS. 
  243 
  

  

  Of 
  the 
  other 
  Chelonians 
  of 
  the 
  London 
  Clay 
  the 
  only 
  form 
  which 
  

   attains 
  dimensions 
  corresponding 
  to 
  that 
  of 
  the 
  jaw 
  before 
  us 
  is 
  

   the 
  species 
  described 
  by 
  Sir 
  It. 
  Owen 
  as 
  Emys 
  Conybeari, 
  which 
  

   has 
  been 
  shown 
  by 
  Mr. 
  Boulenger 
  and 
  myself, 
  in 
  a 
  paper 
  published 
  

   in 
  the 
  ' 
  Geological 
  Magazine 
  ' 
  *, 
  to 
  be 
  a 
  Pleurodiran, 
  and 
  specifically 
  

   identical 
  with 
  the 
  so-called 
  Emys 
  Delabechei. 
  From 
  the 
  marked 
  re- 
  

   semblance 
  of 
  its 
  shell 
  to 
  that 
  of 
  Podocnemis, 
  we 
  provisionally 
  referred 
  

   the 
  species 
  to 
  that 
  genus 
  as 
  P. 
  Delabechei. 
  Now 
  we 
  have 
  already 
  

   seen 
  that 
  the 
  mandible 
  before 
  us 
  presents 
  a 
  certain 
  resemblance 
  to 
  

   that 
  of 
  Podocnemis, 
  and 
  there 
  is 
  accordingly 
  a 
  strong 
  presumption 
  

   that 
  it 
  may 
  belong 
  to 
  the 
  last-mentioned 
  species, 
  which 
  in 
  that 
  case 
  

   will 
  not 
  be 
  referable 
  to 
  Podocnemis. 
  It 
  is, 
  of 
  course, 
  impossible 
  to 
  

   be 
  certain 
  of 
  this 
  identity 
  ; 
  and 
  since, 
  if 
  I 
  am 
  right 
  in 
  considering 
  

   that 
  it 
  is 
  not 
  referable 
  to 
  Pseudotrionyx, 
  our 
  specimen 
  indicates 
  a 
  

   new 
  genus, 
  I 
  propose 
  to 
  regard 
  it 
  as 
  the 
  type 
  of 
  one 
  under 
  the 
  name 
  

   of 
  Dacochelys 
  Delabechei. 
  If 
  this 
  mandible 
  be 
  identical 
  with 
  the 
  so- 
  

   called 
  Emys 
  Delabechei, 
  then 
  Owen's 
  specific 
  name 
  will 
  stand 
  for 
  

   both, 
  but 
  if 
  not, 
  the 
  present 
  specimen 
  will 
  indicate 
  also 
  a 
  new 
  

   species. 
  

  

  7. 
  Tooth 
  of 
  (?) 
  OfiNiTHOPSis/rom 
  the 
  Wealden. 
  

  

  In 
  fig. 
  4, 
  plate 
  iii. 
  of 
  the 
  preceding 
  volume 
  of 
  the 
  Society's 
  i 
  Jour- 
  

   nal,' 
  I 
  figured 
  the 
  tooth 
  of 
  a 
  Sauropodous 
  Dinosaur 
  from 
  the 
  

   Wealden 
  of 
  the 
  Isle 
  of 
  Wight, 
  which 
  I 
  considered 
  might 
  probably 
  be 
  

   referable 
  to 
  Ornithojosis 
  (or 
  Pelorosaurus, 
  if 
  the 
  two 
  be 
  identical 
  and 
  

  

  Pig. 
  7. 
  — 
  Inner 
  surface 
  of 
  the 
  crown 
  of 
  a 
  Tooth 
  of 
  (?) 
  Ornithopsis 
  ; 
  

   from 
  the 
  Wealden 
  of 
  Kent. 
  (Nat. 
  size.) 
  

  

  we 
  employ 
  the 
  earlier 
  name). 
  Eecently, 
  Mr. 
  E. 
  Etheridge 
  showed 
  

   me 
  the 
  crown 
  of 
  a 
  tooth 
  collected 
  by 
  Mr. 
  Willett 
  from 
  the 
  Wealden 
  

   of 
  Kent, 
  which 
  I 
  at 
  once 
  recognized 
  as 
  of 
  the 
  same 
  type 
  as 
  the 
  

   above-mentioned 
  specimen. 
  This 
  specimen 
  (fig. 
  7) 
  I 
  think 
  worthy 
  

   of 
  notice 
  as 
  being 
  the 
  only 
  other 
  example 
  known 
  to 
  me, 
  and 
  as 
  

  

  * 
  Decade 
  3, 
  vol. 
  iv. 
  pp. 
  274, 
  275 
  (1887). 
  

  

  