﻿280 
  PALEONTOLOGY 
  OF 
  ELLINl 
  

  

  Radial* 
  pentagonal, 
  nearly 
  twice 
  as 
  wide 
  at* 
  long, 
  d< 
  1 
  on 
  

  

  their 
  low. 
  r 
  margina 
  to 
  correspond 
  with 
  the 
  depressions 
  in 
  the 
  sub- 
  

   radial 
  plates. 
  They 
  are 
  constricts! 
  across 
  the 
  middle, 
  and 
  pi 
  

   ing 
  on 
  their 
  upper 
  margins, 
  with 
  a 
  distinct 
  sutun 
  

   and 
  the 
  brachial 
  plates. 
  

  

  First 
  brachial 
  quadrangular, 
  tin 
  second 
  pentangnlar, 
  sharply 
  an- 
  

   gular 
  above, 
  giving 
  support 
  on 
  its 
  npper 
  sloping 
  angles 
  to 
  the 
  first 
  

   division 
  of 
  the 
  rays. 
  

  

  The 
  arms 
  on 
  the 
  three 
  anterior 
  rays, 
  after 
  their 
  first 
  division 
  on 
  

   the 
  second 
  radials, 
  divide 
  at 
  least 
  four 
  times, 
  and 
  one 
  of 
  them, 
  the 
  

   left 
  antero-lateral 
  ray 
  live 
  times, 
  the 
  division 
  in 
  t 
  iking 
  

  

  place 
  on 
  the 
  outer 
  branch, 
  as 
  in 
  Zeocrinu$, 
  while 
  the 
  inner 
  bran 
  

   continue 
  Bingle 
  to 
  their 
  t 
  xtrcmities. 
  The 
  divisions 
  generally 
  occur 
  

   on 
  the 
  sixth, 
  eighth, 
  twelfth 
  or 
  sixteenth 
  plate, 
  making 
  ten 
  anna 
  to 
  

   two 
  of 
  these 
  rays, 
  which 
  is 
  probably 
  the 
  normal 
  number, 
  ai 
  

   to 
  the 
  other. 
  On 
  the 
  posterior 
  rays, 
  the.-r 
  divisions 
  take 
  pla 
  

   the 
  fourth, 
  sixth 
  and 
  eighth 
  plates. 
  Tl. 
  an 
  arm 
  forme 
  

  

  fifty 
  arms, 
  as 
  the 
  normal 
  number 
  for 
  this 
  species. 
  

  

  First 
  anal 
  plate 
  hexagonal, 
  about 
  as 
  large 
  as 
  the 
  smallest 
  sub- 
  

   radials, 
  second 
  and 
  third 
  rather 
  Bmaller 
  than 
  the 
  first, 
  and 
  all 
  

   arranged 
  as 
  usual 
  in 
  this 
  genus. 
  Tiny 
  are 
  all 
  depressed 
  at 
  the 
  

   angles, 
  though 
  not 
  quite 
  so 
  much 
  as 
  the 
  other 
  plates 
  of 
  the 
  i 
  

   Column 
  unknown. 
  

  

  Poritionund 
  locality: 
  Upper 
  part 
  of 
  the 
  geodiferous 
  shales 
  of 
  the 
  

   nk 
  group, 
  one 
  mile 
  below 
  Keokuk. 
  

  

  Nos. 
  LOO 
  and 
  186 
  of 
  Mr. 
  L. 
  A. 
  Cox's 
  collection. 
  

  

  PoTKBIOOBUn 
  - 
  LSP] 
  i.mi 
  B, 
  Wortheii. 
  

  

  PL 
  XWiii. 
  l 
  . 
  

  

  ujwralto, 
  

   Bulletin 
  Ro 
  i. 
  ••; 
  •■ 
  

  

  Body 
  depressed, 
  forming 
  ■ 
  low 
  saucer-Like 
  cup 
  below 
  the 
  summit 
  

   of 
  the 
  radial 
  plates. 
  Baa 
  depressed, 
  and 
  basal 
  plat 
  I 
  by 
  

  

  the 
  upper 
  columnar 
  joint-. 
  Suhradials 
  small, 
  their 
  lower 
  ai 
  

   conceal- 
  <\ 
  in 
  the 
  ha-al 
  concau" 
  

  

  Radials 
  about 
  twice 
  as 
  wide 
  as 
  loi 
  si, 
  without 
  any 
  . 
  

  

  defined 
  suture 
  between 
  them 
  and 
  the 
  first 
  brachial 
  plates. 
  

   Brachials 
  two, 
  about 
  the 
  tami 
  :v.\\>. 
  the 
  first 
  qc 
  

  

  Jar, 
  and 
  the 
  second 
  pi 
  otangul 
  i 
  the 
  

  

  us 
  of 
  thl 
  

  

  