﻿810 
  PAL^ONTOLOGI 
  OF 
  ILLINOIf 
  

  

  Column 
  rather 
  Blender, 
  and 
  composed 
  of 
  short, 
  round, 
  even 
  joints. 
  

   Mon 
  and 
  locality; 
  Qpper 
  beds 
  of 
  Keokuk 
  lis 
  . 
  Hamil- 
  

  

  ton, 
  111. 
  

  

  No. 
  171 
  of 
  Mr. 
  L. 
  A. 
  Cox's 
  collection. 
  

  

  B. 
  -After 
  publishing 
  . 
  tlon 
  of 
  this 
  torn 
  

  

  published 
  In 
  :■ 
  Journal 
  of 
  Natural 
  I 
  

  

  typOBrapiuool 
  error, 
  and 
  therefore 
  restore 
  the 
  nami 
  i 
  HallinUEL 
  

  

  Cyatuocrim 
  s 
  Maksiiai.i.kn-i>. 
  Worthen. 
  

  

  PL 
  XXX. 
  Fiji. 
  i. 
  

  

  i 
  <j<i 
  IfarsAaUsfuis, 
  Worxhkv, 
  February, 
  1882. 
  

  

  Bulletin 
  No. 
  l. 
  of 
  the 
  Illinois 
  State 
  Museum 
  of 
  Nuturui 
  , 
  . 
  3S. 
  

  

  Diagnosis: 
  Body 
  mamillate. 
  length 
  ami 
  breadth 
  about 
  equal, 
  ami 
  

   truncated 
  at 
  the 
  babe 
  where 
  it 
  joins 
  the 
  column. 
  Basal 
  plates 
  small, 
  

   longest 
  on 
  the 
  anterior 
  side, 
  angular 
  above, 
  and 
  forming 
  by 
  them- 
  

   selves 
  a 
  shallow 
  pentagonal 
  cup. 
  Bnbradials 
  about 
  as 
  high 
  as 
  wide, 
  

   four 
  of 
  them 
  of 
  equal 
  size 
  and 
  hexagonal, 
  the 
  fifth 
  on 
  tin 
  anterior 
  

   Bide 
  nearly 
  twice 
  as 
  large 
  as 
  the 
  others 
  and 
  heptagonaL 
  I 
  

   on 
  four 
  of 
  the 
  rays 
  are 
  about 
  the 
  same 
  size 
  as 
  the 
  smallest 
  sul 
  c 
  

   dials, 
  pentagonal 
  in 
  form, 
  their 
  lower 
  angles 
  fitting 
  into 
  depressions 
  

   between 
  the 
  subradials, 
  OOnstrioted 
  from 
  the 
  lower 
  lateral 
  angli 
  

   upward, 
  so 
  that 
  the 
  apper 
  margins, 
  which 
  support 
  the 
  brachia 
  

   only 
  about 
  half 
  as 
  wide 
  as 
  the 
  greatest 
  width 
  below. 
  

  

  Brachials 
  three 
  on 
  these 
  four 
  rays, 
  narrower 
  than 
  the 
  rad 
  

   of 
  them 
  quadrangular, 
  and 
  the 
  third 
  angular 
  above, 
  supporting 
  tl 
  

  

  Ural 
  divisions 
  of 
  the 
  arms. 
  The 
  lateral 
  spa* 
  <n 
  th. 
  brach- 
  

  

  ials, 
  and 
  extending 
  below 
  to 
  the 
  middle 
  of 
  the 
  1 
  

   has. 
  linn 
  idled 
  by 
  a 
  calcareous 
  integument, 
  or 
  with 
  minute 
  plat 
  

   that 
  are 
  too 
  small 
  to 
  present 
  definite 
  forms 
  under 
  an 
  ordinary 
  Ldass. 
  

  

  on 
  the 
  anterior 
  Bide 
  of 
  the 
  specimen, 
  the 
  large 
  anterior 
  Bubradial 
  

   is 
  quadrangular 
  radial 
  Lireotly 
  upon 
  its 
  trun- 
  

  

  cated 
  upper 
  margin, 
  and 
  this 
  is 
  suoceeded 
  by 
  two 
  or 
  more 
  quad- 
  

   rangular 
  brachials, 
  beydnd 
  which 
  its 
  structure 
  cannot 
  ;t. 
  

  

  tin 
  first 
  bifurcation 
  <»n 
  the 
  third 
  brachial, 
  dr. 
  

  

  hi 
  on 
  die 
  sixth 
  Mill 
  plate, 
  and 
  some 
  of 
  the 
  brat 
  

  

  or 
  twice 
  mon 
  . 
  higher 
  up. 
  They 
  are 
  oompoaed 
  of 
  rather 
  long, 
  rounds 
  

   quadrangular 
  joint 
  og 
  gradually 
  in 
  size 
  to 
  then- 
  extras 
  

  

  Anal 
  plates 
  unknown. 
  

  

  