﻿210 
  PALAEONTOLOGY 
  OF 
  ll.UNOI 
  

  

  the 
  lower 
  jaw 
  is 
  apparently 
  Bubquadrangular 
  in 
  outtii 
  

   the 
  coronal 
  surface 
  regularly 
  transversely 
  arched 
  into 
  the 
  low 
  prom- 
  

   inence 
  which 
  ocenpies 
  the 
  r 
  part 
  of 
  its 
  area, 
  a 
  shallow 
  d 
  

   pression 
  extending 
  along 
  the 
  outer 
  border; 
  in 
  the 
  

   anterior 
  margin 
  and 
  inner 
  border 
  extends 
  one-fourth 
  or 
  one-third 
  

   the 
  depth, 
  and 
  is 
  marked 
  by 
  delicate 
  vertical 
  rugosities, 
  and 
  dis- 
  

   tinctly 
  defined 
  from 
  the 
  basal 
  portion,— 
  the 
  posterior 
  and 
  

   unknown. 
  The 
  surface 
  of 
  the 
  crown 
  presents 
  an 
  elaboi 
  ilp- 
  

   tured 
  appearance 
  from 
  the 
  delicate 
  ru 
  which 
  are 
  disposed 
  in 
  

   longitudinal 
  lines, 
  a 
  narrow 
  worn 
  Kit 
  along 
  the 
  ant 
  

  

  ing 
  the 
  minute 
  punctate 
  structure, 
  the 
  surface 
  here 
  also 
  showi 
  

   faint 
  transverse 
  undulation.-. 
  The 
  BUpposed 
  maxillary 
  form 
  p 
  

   a 
  broad 
  shallow 
  concavity 
  in 
  the 
  transverse 
  diameter, 
  and 
  v 
  

   gently 
  arched 
  longitudinally/.the 
  enamel 
  forming 
  a 
  well-defined 
  belt, 
  

   deeper 
  along 
  the 
  inner 
  articular 
  border 
  than 
  at 
  theanterii 
  mar- 
  

  

  gin, 
  which 
  is 
  rather 
  strongly 
  inbeveled. 
  The 
  coronal 
  surf;! 
  

   an 
  exceedingly 
  intricate 
  rugose 
  ornamentation, 
  the 
  ru 
  pat- 
  

  

  ently 
  not 
  conforming 
  to 
  any 
  definite 
  direction. 
  The 
  examples 
  

   a 
  breadth 
  of 
  40 
  to 
  50 
  millimetres, 
  hut 
  they 
  are 
  too 
  imperfect 
  to 
  show 
  

   details 
  other 
  than 
  those 
  noticed. 
  

  

  The 
  first 
  noticed 
  form 
  Lear- 
  marked 
  resemblance 
  to 
  thi 
  

   spondinj,' 
  form 
  of 
  Psammodua 
  Lovianus 
  in 
  outline 
  and 
  contour, 
  so 
  far 
  

   as 
  these 
  features 
  are 
  decipherable, 
  and 
  the 
  peculiar 
  rugose 
  ornan 
  

   tationof 
  the 
  coronal 
  surface 
  may 
  be 
  that 
  of 
  a 
  tooth 
  which 
  lias 
  1- 
  

   less 
  exposed 
  to 
  wear 
  than 
  the 
  examples 
  noticed 
  under 
  the 
  la' 
  

   Bpecific 
  designation, 
  still 
  the 
  present 
  tooth 
  differs 
  from 
  that 
  form 
  

   i,, 
  having 
  a 
  m 
  ralar 
  inner 
  border, 
  the 
  crown 
  in 
  /'. 
  / 
  

  

  being 
  rounded 
  to 
  the 
  enamel 
  belt 
  <>f 
  the 
  articular 
  border. 
  In 
  n 
  

   tion 
  to 
  the 
  companion 
  tooth 
  described 
  above, 
  its 
  mutilated 
  condil 
  

   hardly 
  affords 
  the 
  necessary 
  .lata 
  for 
  the 
  n 
  D 
  of 
  it- 
  and 
  

  

  coronal 
  contour, 
  hut 
  the 
  beautiful 
  ornamentation 
  of 
  thi 
  W< 
  11 
  

  

  displayed. 
  In 
  the 
  latter 
  character 
  the 
  tooth 
  

   the 
  specimen 
  with 
  which 
  it 
  is 
  provisionallj 
  

   inclined 
  to 
  regard 
  their 
  Bpecific 
  identity 
  as 
  improbable. 
  In 
  

   culiar 
  Bculpturing 
  of 
  the 
  coronal 
  Burf* 
  

  

  ii„. 
  Keokul 
  P. 
  grandit, 
  though 
  thi 
  of 
  the 
  

  

  alar 
  than 
  obtains 
  in 
  the 
  hit 
  

   station 
  afford 
  mi 
  nt 
  of 
  a 
  small 
  

  

  to 
  the 
  form 
  indivi 
  i 
  whioh 
  we 
  ha 
  

  

  ||„ 
  ~|„ 
  oific 
  d. 
  ■ 
  i 
  ■nation 
  P$amn 
  

  

  ■ 
  t 
  of 
  th. 
  outer 
  bord< 
  r, 
  wl 
  mewhal 
  obli 
  

  

  em. 
  

  

  