﻿330 
  PALEONTOLOGY 
  OF 
  ILLINOIS. 
  

  

  Okdki: 
  OPHIUROIDE 
  \ 
  

   Teematastbb, 
  n. 
  gen. 
  

  

  ■i. 
  mi 
  opening; 
  tutt 
  r, 
  ■ 
  

  

  Body 
  stellate, 
  central 
  part 
  discoid, 
  rays 
  long, 
  flexaooa 
  and 
  gradu- 
  

   ally 
  tapering. 
  Kays 
  consisting 
  ol 
  a 
  double 
  series 
  of 
  amhulacral 
  

   plates, 
  forming, 
  together, 
  a 
  Bubcuneiform 
  series 
  with 
  the 
  tapering 
  

  

  ends 
  directed 
  toward 
  the 
  apices 
  of 
  the 
  rays 
  and 
  uniting 
  with 
  tin- 
  

   larger 
  ends 
  of 
  the 
  succeeding 
  double 
  plates, 
  upon 
  each 
  side 
  of 
  which 
  

   there 
  is 
  a 
  series 
  of 
  curved 
  adambulaoral 
  plates, 
  which 
  form 
  the 
  

   margins 
  of 
  the 
  rays. 
  The 
  pores 
  are 
  large 
  and 
  situated 
  I 
  he 
  

  

  contracting 
  sides 
  of 
  the 
  amhulacral 
  plates 
  and 
  the 
  concave 
  sides 
  of 
  

   the 
  curving 
  adaxnbulaorals. 
  Four 
  plates 
  border 
  upon 
  each 
  pore 
  

   though 
  nearly 
  surrounded 
  by 
  two 
  of 
  them. 
  Plates 
  ten. 
  I 
  ur- 
  

  

  face 
  unknown. 
  

  

  This 
  genus 
  is 
  distinguished 
  by 
  the 
  parallel 
  arrangement 
  of 
  the 
  

   ambulaorals 
  and 
  adambulaorals, 
  instead 
  of 
  the 
  alternate 
  order, 
  and 
  

  

  by 
  the 
  Large 
  poi 
  

  

  Tkkmatastki: 
  DITFIOU 
  i-. 
  Bp. 
  nov. 
  

  

  PL 
  XXXI, 
  0s. 
  a 
  *> 
  Tenti 
  nlflad 
  two 
  dlametan 
  

  

  the 
  arrangement 
  "f 
  t)i" 
  i«in«<-?- 
  magnified 
  tour 
  dial 
  

  

  Body 
  Btellate, 
  diets 
  small, 
  rays 
  long, 
  Bexuous 
  and 
  gradually 
  tapering. 
  

  

  Ambulacra] 
  plates 
  subtrigonal, 
  tted, 
  and 
  united 
  upon 
  their 
  

  

  Btraighl 
  faces 
  in 
  parallel 
  order, 
  so 
  as 
  to 
  form 
  a 
  iub- 
  

  

  ouneifbrm 
  sections 
  at 
  the 
  bottom 
  of 
  the 
  ambnlaoi 
  ith 
  tin 
  

  

  tapering 
  end 
  of 
  each 
  directed 
  toward 
  the 
  apex 
  of 
  the 
  ray, 
  and 
  unit 
  

   with 
  tlie 
  larger 
  end 
  of 
  the 
  next 
  m 
  able 
  plal 
  

  

  Adambulaoral 
  i>lates 
  paraUel 
  with 
  the 
  ambulaorals, 
  and 
  each 
  forms 
  

  

  a 
  0UTT6 
  from 
  the 
  ihl 
  of 
  an 
  amhulacral 
  toward 
  I 
  of 
  

  

  the 
  ray. 
  to 
  unite 
  with 
  the 
  ne\t 
  BUCOeeding 
  adamhulacral 
  as 
  i: 
  

   away 
  from 
  its 
  attachment 
  to 
  the 
  amhulacral. 
  By 
  th: 
  

  

  ruotion 
  the 
  adambulaorals 
  are 
  fixed, 
  at 
  one 
  end, 
  to 
  the 
  ambula- 
  

  

  dt, 
  while 
  the 
  other 
  end 
  moves 
  upon 
  the 
  curved 
  BUI 
  an 
  

  

  adambulaoral 
  allow 
  the 
  same 
  lateral 
  Aexibilit] 
  of 
  ti 
  

  

  oared 
  in 
  othi 
  j 
  th.- 
  alternate 
  arrs 
  * 
  of 
  the 
  plal 
  

  

  Th. 
  ad 
  situated 
  i 
  

  

  