﻿PALEONTOLOGY 
  OP 
  ILLINOIS. 
  

  

  Zxaobzkds 
  I 
  ' 
  i 
  k 
  i 
  n 
  > 
  i 
  - 
  , 
  Vrorthen. 
  

  

  PL 
  xw 
  

  

  Bulletin 
  "f 
  the 
  Qllnola 
  E 
  tun 
  "f 
  Natural 
  History, 
  i 
  I 
  

  

  ly 
  of 
  medium 
  aize, 
  short, 
  Forming 
  below 
  the 
  summit 
  of 
  : 
  ; 
  

   9 
  a 
  -hallow 
  cup 
  about 
  three 
  times 
  as 
  wide 
  as 
  high. 
  -mall 
  

  

  and 
  entirely 
  concealed 
  in 
  the 
  basal 
  concavity. 
  Suhradials 
  rather 
  

   longer 
  than 
  wide, 
  and 
  curving 
  below 
  BO 
  a> 
  to 
  form 
  a 
  part 
  of 
  the 
  

   concavity 
  of 
  the 
  base. 
  

  

  Radials 
  pentagonal 
  once 
  and 
  a 
  half, 
  and 
  the 
  anterior 
  one 
  prob- 
  

   ably 
  twice 
  as 
  wide 
  as 
  long, 
  ami 
  truncated 
  squarely 
  aoross 
  their 
  upper 
  

   margins 
  for 
  the 
  reception 
  <>f 
  the 
  brachial 
  series. 
  

  

  The 
  anterior 
  ray 
  has 
  three 
  brachials, 
  the 
  first 
  one 
  of 
  which 
  is 
  as 
  

   large 
  as 
  the 
  radial 
  below, 
  the 
  second 
  one 
  rery 
  Bhort, 
  and 
  

   quadrangular; 
  the 
  third 
  is 
  also 
  short, 
  hut 
  pentangular, 
  supporting 
  

  

  on 
  it- 
  sloping 
  sidrb 
  the 
  first 
  divisions 
  of 
  the 
  ray. 
  One 
  of 
  these 
  di- 
  

   visions 
  bifurcates 
  again 
  on 
  the 
  eighth 
  plate, 
  and 
  the 
  other 
  on 
  the 
  

   tenth, 
  beyond 
  which 
  they 
  appear 
  to 
  lie 
  simple 
  to 
  their 
  extremities, 
  

  

  making 
  hut 
  four 
  arms 
  to 
  this 
  ray. 
  The 
  righl 
  anterolateral 
  ray 
  and 
  

   the 
  left 
  posterior 
  ray 
  have 
  each 
  a 
  single 
  brachial, 
  which 
  is 
  nearly 
  

   as 
  long 
  as 
  wide, 
  supporting 
  on 
  its 
  sloping 
  angles 
  the 
  first 
  divia 
  

   of 
  the 
  rays. 
  The 
  two 
  divisions 
  of 
  the 
  right 
  anterolateral 
  ray 
  divide 
  

   again 
  on 
  the 
  Birth 
  plate, 
  ami 
  at 
  least 
  one 
  of 
  these 
  divisions, 
  and 
  

   probably 
  both 
  the 
  outer 
  oik-, 
  divide 
  again 
  on 
  the 
  tenth 
  plate, 
  making 
  

  

  six 
  arms 
  to 
  this 
  ray. 
  If 
  the 
  other 
  r.i 
  -pond 
  with 
  this, 
  it 
  would 
  

  

  give 
  twenty-eight 
  arms 
  as 
  the 
  full 
  series 
  for 
  ti. 
  

  

  unknown. 
  Column 
  slender, 
  and 
  composed 
  of 
  round 
  joints 
  of 
  unequal 
  

  

  thickness. 
  

  

  logical 
  j»>siti,»i 
  ,i,i,i 
  locality 
  i 
  Lower 
  part 
  of 
  the 
  Burlington 
  lime- 
  

   ae, 
  Montezuma. 
  Pike 
  county. 
  Qlino 
  

   No. 
  2, 
  162, 
  Dlinois 
  state 
  coil, 
  otion. 
  

  

  