﻿10 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol.67 
  

  

  I 
  also 
  give 
  for 
  comparison 
  (pi. 
  1) 
  some 
  figures 
  of 
  the 
  type 
  species 
  

   of 
  Herpetocrinus, 
  H. 
  fletcheri, 
  from 
  the 
  Wenlock 
  limestone 
  at 
  

   Dudley, 
  England, 
  including 
  my 
  own 
  specimen 
  which 
  shows 
  the 
  

   crown 
  to 
  consist 
  of 
  4 
  rays 
  7 
  ; 
  also 
  Salter's 
  type 
  specimen 
  in 
  the 
  

   Geological 
  Museum 
  at 
  Cambridge, 
  England, 
  with 
  the 
  crown 
  ex- 
  

   posed 
  on 
  one 
  side. 
  In 
  these, 
  and 
  in 
  two 
  other 
  specimens 
  in 
  my 
  col- 
  

   lection, 
  the 
  bead-like 
  form 
  of 
  the 
  slender 
  cirri, 
  which 
  is 
  the 
  chief 
  

   distinctive 
  character 
  separating 
  it 
  from 
  the 
  closely 
  related 
  Amer- 
  

   ican 
  species, 
  is 
  thoroughly 
  shown. 
  There 
  is 
  some 
  irregularity 
  in 
  

   their 
  distribution, 
  as 
  is 
  said 
  by 
  Bather 
  8 
  ; 
  and 
  I 
  find 
  more 
  alternation 
  

   in 
  successive 
  columnals 
  than 
  his 
  description 
  indicates. 
  H. 
  -fletcheri 
  

   occurs 
  both 
  in 
  England 
  and 
  Gotland, 
  and 
  for 
  a 
  complete 
  revised 
  de- 
  

   scription 
  see 
  Bather's 
  work 
  previously 
  cited, 
  especially 
  his 
  beautiful 
  

   figures 
  on 
  plate 
  2, 
  and 
  details 
  of 
  the 
  stem 
  structure 
  on 
  page 
  41. 
  

  

  Horizon 
  and 
  locality. 
  — 
  Silurian, 
  Eochester 
  shale, 
  and 
  also 
  the 
  

   later 
  Clinton; 
  Lockport, 
  New 
  York; 
  Brassfield 
  limestone, 
  Xenia, 
  

   Ohio; 
  Kacine 
  dolomite', 
  Chicago; 
  also 
  the 
  Wenlock 
  limestone; 
  

   Dudley, 
  England, 
  and 
  Gotland, 
  Sweden. 
  

  

  MYELODACTYLUS 
  BREVIS, 
  new 
  species 
  

  

  Plate 
  1, 
  figs. 
  9, 
  9a 
  

  

  I 
  figure 
  under 
  this 
  name 
  a 
  solitary 
  specimen 
  from 
  the 
  Browns- 
  

   port 
  formation 
  of 
  the 
  late 
  Niagaran, 
  which 
  agrees 
  with 
  M. 
  convolutus 
  

   in 
  all 
  the 
  diagnostic 
  characters 
  of 
  the 
  columnals 
  and 
  cirri, 
  but 
  differs 
  

   in 
  the 
  extreme 
  shortness 
  of 
  the 
  stem, 
  and 
  the 
  close 
  coil. 
  It 
  has 
  no 
  

   distal 
  extension 
  whatever 
  beyond 
  the 
  tightly 
  rolled 
  coil, 
  as 
  is 
  shown 
  

   by 
  the 
  rapid 
  taper, 
  which 
  is 
  evidently 
  very 
  near 
  the 
  end. 
  While 
  

   the 
  specimen 
  may 
  be 
  sporadic 
  amid 
  the 
  great 
  abundance 
  of 
  the 
  pre- 
  

   valent 
  species 
  of 
  that 
  horizon, 
  yet 
  the 
  agreement 
  with 
  the 
  form 
  from 
  

   the 
  Eochester 
  shale 
  in 
  the 
  essentials 
  of 
  cirri 
  structure 
  is 
  so 
  complete 
  

   that 
  it 
  can 
  hardly 
  be 
  ignored, 
  while 
  at 
  the 
  same 
  time 
  the 
  close 
  coil, 
  

   terminating 
  in 
  a 
  point, 
  is 
  shown 
  by 
  abundant 
  material 
  in 
  another 
  

   form 
  to 
  be 
  a 
  good 
  specific 
  character. 
  

  

  Horizon 
  and 
  locality. 
  — 
  Silurian, 
  Brownsport 
  formation; 
  Decatur 
  

   county, 
  Tennessee. 
  

  

  MYELODACTYLUS 
  AMMONIS 
  (Bather) 
  

  

  Plate 
  2, 
  figs. 
  1-9 
  

  

  Herpetocrvnus 
  ammonia 
  Bather, 
  Crinoidea 
  of 
  Gotland, 
  1893, 
  p. 
  49. 
  pi. 
  2, 
  figs. 
  

   54-63. 
  

  

  Coil 
  very 
  close, 
  stem 
  short, 
  extending 
  but 
  little 
  beyond 
  the 
  prox- 
  

   imal 
  part 
  of 
  the 
  involute 
  coil 
  ; 
  wide 
  in 
  the 
  middle 
  region 
  and 
  taper- 
  

   ing 
  to 
  a 
  point 
  at 
  the 
  distal 
  end. 
  Cirri 
  numerous, 
  short, 
  flat 
  and 
  

  

  7 
  Mentioned 
  by 
  Bather 
  in 
  Crinoidea 
  of 
  Gotland, 
  p. 
  1S2, 
  under 
  fig. 
  38. 
  

  

  8 
  Crinoidea 
  of 
  Gotland, 
  p. 
  46. 
  

  

  