﻿92 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL, 
  MUSEUM 
  vol. 
  67 
  

  

  DECADOCRINUS 
  TUMIDULUS 
  (Miller 
  and 
  Gurley) 
  

  

  Plate 
  17, 
  fig. 
  6. 
  

  

  Cyathocrinus 
  tumidulus 
  Miller 
  and 
  Gurley, 
  Bull. 
  3, 
  111. 
  State 
  Mus., 
  p. 
  

  

  31, 
  pi. 
  3, 
  fig. 
  7. 
  

   Decadocrinus 
  grandis 
  Wachsmuth 
  and 
  Springer, 
  North 
  Amer. 
  Crin. 
  

  

  Cam., 
  1897, 
  pi. 
  7, 
  figs. 
  4, 
  5.— 
  Springer, 
  Amer. 
  Geol., 
  vol. 
  26, 
  1900, 
  pi. 
  

  

  16, 
  figs. 
  5, 
  6. 
  

   Keokuk 
  limestone 
  ; 
  Indian 
  creek 
  and 
  Canton, 
  Indiana. 
  

  

  A 
  very 
  striking 
  species, 
  numerously 
  represented 
  at 
  its 
  principal 
  

   locality, 
  and 
  illustrating 
  the 
  development 
  of 
  the 
  genus 
  through 
  the 
  

   later 
  formations. 
  A 
  specimen 
  showing 
  the 
  anal 
  opening 
  about 
  

   midway 
  was 
  figured 
  in 
  the 
  Canierata 
  monograph, 
  erroneously 
  

   designated 
  as 
  D. 
  grandis. 
  

  

  Genus 
  SCYTALOCRINUS 
  Wachsmuth 
  and 
  Springer 
  

  

  Scytalocrinus 
  Wachsmuth 
  and 
  Springer, 
  Rev. 
  Pal., 
  pt. 
  1, 
  1879, 
  p. 
  116. 
  

   Devonian 
  to 
  Upper 
  Carboniferous. 
  

  

  SCYTALOCRINUS 
  VALIDUS 
  Wachsmuth 
  and 
  Springer 
  

  

  Plate 
  17, 
  figs. 
  7, 
  8 
  

  

  Scytalocrinus 
  validtis 
  Wachsmuth 
  and 
  Springer, 
  North 
  Amer. 
  Crin. 
  

  

  Cam., 
  1897, 
  pi. 
  7, 
  figs. 
  2a, 
  o, 
  3.— 
  Springer, 
  Amer. 
  Geol., 
  vol. 
  26, 
  1900, 
  

  

  pi. 
  16, 
  figs. 
  9, 
  10. 
  

   Keokuk 
  limestone; 
  Indian 
  Creek 
  Indiana. 
  

  

  A 
  characteristic 
  example 
  of 
  the 
  genus, 
  except 
  in 
  the 
  rather 
  de- 
  

   pressed 
  calyx; 
  selected 
  to 
  show 
  the 
  anal 
  opening 
  in 
  the 
  sac 
  mid- 
  

   way, 
  and 
  the 
  single 
  arm 
  as 
  sometimes 
  found 
  in 
  the 
  anterior 
  ray. 
  

  

  Genus 
  TIMOROCRINUS 
  Wanner, 
  1912, 
  1916, 
  1924 
  

  

  Timorocrinus 
  Wanner, 
  Perm. 
  Krin. 
  Timor, 
  vol. 
  2, 
  1924, 
  pp. 
  54, 
  63, 
  181, 
  

   269. 
  — 
  Jaekel, 
  Phylogenie 
  und 
  System 
  der 
  Pelmatozoen, 
  1916, 
  p. 
  64. 
  

  

  The 
  relation 
  of 
  this, 
  the 
  most 
  abundant 
  and 
  heretofore 
  the 
  most 
  

   mysterious 
  of 
  all 
  the 
  Timor 
  crinoids, 
  was 
  satisfactorily 
  settled 
  by 
  

   Professor 
  Wanner 
  in 
  his 
  latest 
  discussion 
  in 
  1924. 
  He 
  now 
  recedes 
  

   from 
  his 
  former 
  view 
  referring 
  it 
  to 
  the 
  Flexibilia, 
  and 
  concludes, 
  

   following 
  the 
  opinion 
  of 
  Jaekel, 
  that 
  this 
  remarkable 
  genus, 
  super- 
  

   ficially 
  unlike 
  any 
  other 
  known 
  crinoid, 
  belongs 
  to 
  the 
  Inadunate 
  

   family 
  Poteriocrinidae. 
  It 
  has 
  a 
  strongly 
  inflated 
  ventral 
  sac, 
  

   strengthened 
  by 
  numerous 
  projecting 
  longitudinal 
  ridges 
  of 
  differ- 
  

   ent 
  grades, 
  separated 
  by 
  corresponding 
  furrows, 
  in 
  which 
  the 
  deli- 
  

   cate 
  arms 
  and 
  their 
  branches 
  were 
  lodged, 
  probably 
  for 
  protection. 
  

   The 
  sac 
  is 
  connected 
  with 
  the 
  dorsal 
  cup 
  by 
  means 
  of 
  a 
  single 
  strong 
  

   anal, 
  or 
  proximal, 
  plate 
  meeting 
  the 
  greatly 
  enlarged 
  posterior 
  basal. 
  

   Basals 
  are 
  unequal, 
  infrabasals 
  fused 
  and 
  buried 
  under 
  the 
  column. 
  

   Anal 
  opening 
  is 
  near 
  the 
  top 
  of 
  the 
  sac, 
  but 
  on 
  the 
  posterior 
  side 
  

  

  