﻿184 
  PALEONTOLOGY 
  OF 
  ILLINOl 
  

  

  minute 
  punctaa, 
  haying 
  individually 
  tin- 
  appearance 
  of 
  a 
  minute 
  

   central 
  cone 
  Burrounded 
  by 
  a 
  Blightly 
  raised 
  rim, 
  and 
  collectively 
  

   arranged 
  in 
  very 
  regular, 
  Beldom 
  bifurcating 
  or 
  implanted 
  transvi 
  

   parated 
  by 
  angular 
  carina) 
  which 
  appear 
  to 
  form 
  one 
  - 
  

   of 
  the 
  riins 
  of 
  the 
  medullary 
  tula-.-. 
  Tin 
  illustrate 
  an 
  

  

  accurate 
  idea 
  of 
  the 
  Bize 
  and 
  relative 
  proportions 
  of 
  tin- 
  form 
  indi- 
  

   cal 
  

  

  Apparently 
  possessing 
  unmistakable 
  generic 
  relations 
  with 
  Xyttro- 
  

   dm, 
  tin- 
  species 
  above 
  indicated 
  differs 
  from 
  the 
  Chester 
  A'. 
  

  

  verus, 
  in 
  the 
  details 
  <>f 
  contour 
  of 
  the 
  articular 
  area 
  of 
  the 
  antero- 
  

   2--j?^« 
  lateral, 
  and 
  the 
  proportionally 
  greater 
  breadth 
  of 
  tie 
  

  

  "» 
  The 
  unique 
  example 
  described 
  was 
  discovered 
  by 
  Mr. 
  Win. 
  Gui 
  

   in 
  the 
  shales 
  immediately 
  overlying 
  Coal 
  No. 
  7, 
  Lower 
  Goal 
  M 
  

   of 
  the 
  Illinois 
  general 
  section 
  at 
  Danville. 
  

  

  (;knt> 
  SAXDALODUS, 
  N.andW. 
  

   Sandalobus 
  0OMPLANATU8, 
  (N. 
  and 
  \Y. 
  

  

  PL 
  XII, 
  Fig. 
  1-4. 
  

   1 
  . 
  i.i:ki.y 
  and 
  WOSTHSH, 
  18BS, 
  III. 
  Geol. 
  Surv.. 
  Q. 
  p. 
  98, 
  PL 
  IX, 
  L 
  4. 
  

  

  onodus 
  in. 
  1 
  1.1. 
  v 
  sad 
  WoBtmat, 
  1806, 
  lb. 
  EL 
  p. 
  US. 
  PL 
  M. 
  I 
  

  

  The 
  tonus 
  originally 
  noticed 
  under 
  the 
  above 
  cited 
  nanus 
  consti- 
  

  

  a 
  characteristic 
  group 
  or 
  Bpeoies 
  ol 
  Sandolodut, 
  as 
  much 
  so 
  

   indeed 
  as 
  dots 
  the 
  type 
  of 
  the 
  genua 
  8, 
  l« 
  rissimiix, 
  N. 
  an.l 
  W. 
  The 
  

   illustrations 
  of 
  this 
  Bpeoies 
  which 
  are 
  now 
  introduce. 
  1 
  Buffice 
  to 
  bUow 
  

   the 
  generic 
  relationship 
  and 
  the 
  probable 
  specific 
  identity 
  of 
  the 
  two 
  

  

  forms 
  alluded 
  to 
  in 
  the 
  aho\e 
  synonymy. 
  Both 
  of 
  tin 
  al 
  

  

  riptions 
  apply 
  to 
  what 
  we 
  regard 
  as 
  probably 
  the 
  posterior 
  form 
  

   of 
  the 
  mandible, 
  that 
  referred 
  to 
  under 
  the 
  term 
  Deltodm 
  complana- 
  

   ins 
  representing 
  a 
  crushed 
  and 
  distorted 
  depressed 
  tooth, 
  examples 
  

   of 
  which 
  aii 
  of 
  more 
  frequent 
  occurrence 
  in 
  the 
  col 
  than 
  are 
  

  

  thosi 
  corresponding 
  with 
  the 
  extremely 
  convex 
  examples 
  which 
  afford 
  

   the 
  type 
  of 
  Trigonodm 
  mayor. 
  While 
  these 
  Bomewhal 
  pronou 
  

   varl 
  m 
  to 
  1" 
  quite 
  distinct, 
  viewed 
  in 
  th< 
  

  

  n 
  like 
  that 
  before 
  as 
  leads 
  to 
  Lb 
  m 
  of 
  

  

  their 
  Bpeoifio 
  identity. 
  

  

  \\. 
  idee 
  the 
  teeth 
  referred 
  to 
  the 
  mandibular 
  posterior 
  form, 
  the 
  

   collet 
  contain 
  a 
  mplea 
  exactly 
  correepondii 
  

  

  the 
  form 
  which 
  we 
  have 
  referred 
  to 
  the 
  opposed 
  position 
  

  

  

  