﻿Plate 
  13. 
  

  

  All 
  figures 
  natural 
  size 
  unless 
  otherwise 
  noted 
  

  

  Page 
  

   TALAROCRINUS 
  PATEI 
  Miller 
  and 
  Gurley 
  46 
  

  

  Figs. 
  1, 
  2, 
  3, 
  4. 
  A 
  series 
  of 
  complete 
  crowns, 
  part 
  of 
  a 
  colony 
  of 
  several 
  

   hundred 
  specimens 
  from 
  one 
  locality; 
  showing 
  variation 
  in 
  

   number 
  of 
  arms 
  from 
  4, 
  3, 
  and 
  rarely 
  2 
  to 
  the 
  ray. 
  Fig. 
  3 
  

   shows 
  a 
  normal 
  anal 
  plate, 
  completely 
  separating 
  the 
  adjacent 
  

   radials. 
  

   5. 
  A 
  specimen 
  with 
  abnormal 
  anal 
  plate, 
  wedge 
  shaped, 
  with 
  the 
  

   two 
  radials 
  meeting 
  above 
  it 
  — 
  a 
  variation 
  toward 
  Pteroto- 
  

   crinus. 
  

   6-12. 
  A 
  series 
  of 
  calices 
  from 
  the 
  same 
  colony 
  showing 
  different 
  

   forms 
  of 
  tegmen, 
  in 
  which 
  the 
  axillary 
  ambulacral 
  is 
  but 
  

   slightly 
  developed, 
  or 
  not 
  at 
  all. 
  Fig. 
  12 
  is 
  enlarged 
  X 
  2. 
  

  

  13. 
  Lateral 
  view 
  of 
  a 
  calyx 
  in 
  which 
  the 
  axillary 
  ambulacrals 
  are 
  

  

  developed 
  into 
  strong 
  nodes, 
  two 
  of 
  which 
  have 
  been 
  displaced, 
  

   affording 
  a 
  view 
  of 
  the 
  facets 
  in 
  which 
  they 
  were 
  seated. 
  

   13a 
  is 
  the 
  nodose 
  ambulacral 
  which 
  came 
  out 
  of 
  the 
  facet 
  

   seen 
  directly 
  at 
  the 
  front. 
  X 
  2. 
  

  

  14. 
  Basal 
  view 
  of 
  calyx. 
  

  

  Lower 
  Chester, 
  Ohara 
  formation, 
  formerly 
  called 
  St. 
  Louis, 
  

   and 
  afterwards 
  Ste. 
  Genevieve 
  ; 
  near 
  Sample, 
  Breckinridge 
  

   County, 
  Kentucky. 
  

  

  TALAROCRINUS 
  SEX-LOBTUS 
  Shumard 
  46 
  

  

  Fig. 
  15. 
  Specimen 
  with 
  very 
  strong 
  spines, 
  closely 
  resembling 
  the 
  form 
  

   of 
  these 
  plates 
  in 
  some 
  species 
  of 
  Pterotocrimis. 
  X 
  2. 
  

   Upper 
  Chester, 
  Gasper 
  formation; 
  Flagpoint, 
  Virginia. 
  

  

  PTEROTOCRINUS 
  ACUTUS 
  Wetherby— 
  50 
  

  

  Fig. 
  16. 
  The 
  axillary 
  ambulacrals 
  hypertrophied 
  into 
  large, 
  club-shaped 
  

   appendages, 
  tapering 
  to 
  a 
  point. 
  The 
  remainder 
  of 
  the 
  tegmen 
  

   is 
  covered 
  by 
  a 
  Platyceras 
  permanently 
  attached 
  over 
  the 
  anus 
  

   for 
  feeding 
  commensally 
  upon 
  the 
  excrement 
  of 
  the 
  crinoid. 
  

   Upper 
  Chester, 
  Glen 
  Dean 
  formation; 
  Sloan's 
  Valley, 
  Pu- 
  

   laski 
  County, 
  Kentucky. 
  

  

  PTEROTOCRINUS 
  RUGOSUS 
  Lyon 
  and 
  Cassedaj 
  47 
  

  

  Figs. 
  17, 
  IS, 
  19, 
  20. 
  Lyon's 
  type 
  (17) 
  with 
  thin 
  wing-like 
  processes; 
  and 
  

   other 
  specimens 
  showing 
  basal, 
  lateral, 
  and 
  tegminal 
  views 
  — 
  

   the 
  latter 
  especially 
  showing 
  the 
  facets 
  in 
  which 
  the 
  proc- 
  

   esses 
  are 
  seated. 
  

  

  Upper 
  Chester, 
  Gasper 
  formation: 
  Breckinridge 
  County, 
  

   Kentucky. 
  

   23832—20 
  9 
  1 
  1 
  7 
  

  

  