﻿223 
  

  

  PALEONTOLOGY 
  OF 
  ILLINOIS. 
  

  

  upon 
  the 
  jaws, 
  we 
  have 
  y, 
  . 
  to 
  ascertain 
  the 
  relative 
  disposition 
  of 
  

   Ul 
  ;: 
  v*™*** 
  ^th 
  thereupon. 
  The 
  peculiar 
  character 
  of 
  the 
  inner 
  

   articular 
  border 
  permits 
  of 
  coadaptation 
  neither 
  with 
  oppositea 
  of 
  

   ""• 
  , 
  " 
  1 
  "'- 
  ^r 
  with 
  the 
  other 
  forms 
  with 
  the 
  remains 
  of 
  which 
  

   resent 
  one 
  is 
  associated, 
  and 
  we 
  are 
  left 
  in 
  doubt 
  even 
  as 
  to 
  

   the 
  generic 
  identity 
  of 
  the 
  latter. 
  The 
  crescent-shaped 
  outline 
  of 
  the 
  

   inner 
  articukr 
  faces 
  indicate 
  a 
  corresponding 
  convexity 
  for 
  the 
  outer 
  

   bolder 
  o 
  the 
  teeth 
  of 
  th, 
  contiguous 
  row 
  articulating 
  with 
  this 
  

   orm. 
  rhe 
  space 
  intervening 
  between 
  opposite 
  individuals 
  of 
  the 
  

   form 
  is 
  ungulate 
  in 
  shape, 
  hut 
  whether 
  it 
  was 
  occupied 
  by 
  a 
  sin 
  

   row 
  of 
  hngulato 
  teeth, 
  or 
  that 
  these 
  were 
  further 
  subdivided 
  can 
  

   only 
  be 
  conjectured. 
  On 
  the 
  other 
  hand, 
  if 
  the 
  dental 
  formula 
  

   r;'' 
  1 
  ' 
  1 
  " 
  1 
  ;" 
  :1 
  " 
  ^Burlington 
  P 
  . 
  Springeri, 
  which 
  seems 
  

  

  " 
  '"' 
  * 
  e 
  " 
  ou 
  *°ed, 
  attributing 
  to 
  it 
  a 
  simple 
  biserial 
  arrangement, 
  

   be 
  regarded 
  a. 
  typical 
  of 
  the 
  genus, 
  then 
  we 
  should 
  have' 
  in 
  the 
  

   Resent 
  Forma 
  new 
  element 
  further 
  complicating 
  the 
  dental 
  formula 
  

   to 
  an 
  extent 
  which, 
  if 
  nut 
  with 
  in 
  existing 
  Myliodonts, 
  might 
  con- 
  

   stitute 
  a 
  distinctive 
  feature 
  of 
  generic 
  significance. 
  We 
  are 
  how- 
  

   ever, 
  fully 
  cognizant 
  of 
  the 
  mea* 
  of 
  .he 
  data 
  at 
  this 
  th 
  

  

  possessed, 
  and 
  would 
  dearly 
  discrim- 
  

   inate 
  between 
  the 
  facta 
  themseh 
  

   and 
  that 
  which 
  they 
  BUggest 
  with 
  

   greater 
  or 
  less 
  degree 
  of 
  plausibility. 
  

   I'ln 
  accompanying 
  diagram 
  repn 
  - 
  

   ats 
  the 
  simples! 
  dental 
  combina- 
  

   tion 
  of 
  the 
  form 
  lure 
  particularly 
  

   alluded 
  to. 
  The 
  lingulate 
  teeth 
  

   tlie 
  median 
  row 
  certainly 
  offer 
  Btrong 
  

   emblanci 
  to 
  aom< 
  oJ 
  the 
  g< 
  neric 
  

   forms 
  with 
  which 
  Copodtu 
  cornutut, 
  

   ooiated 
  ; 
  hut 
  none 
  such 
  

   have 
  been 
  recognized 
  in 
  tin 
  pn 
  

  

  True, 
  we 
  bav< 
  a 
  Form 
  occur- 
  

  

  ' 
  in 
  the 
  same 
  horizon 
  with 
  the 
  

  

  tbe 
  la 
  up: 
  hut 
  it 
  dearly 
  has 
  

  

  no 
  intim 
  itionship 
  with 
  the 
  

  

  form 
  in 
  question. 
  

  

  The 
  Few 
  individuals 
  mentioned 
  

   abov( 
  as 
  comprising 
  th< 
  

  

  

  