﻿British. 
  Fossil 
  CrinoiJs. 
  2i)l 
  

  

  IBB 
  3, 
  two 
  large 
  and 
  one, 
  the 
  r. 
  post., 
  small. 
  Height 
  of 
  

   r. 
  post. 
  IB, 
  3'9 
  mm. 
  Stem-facet 
  circular, 
  not 
  clearly 
  seen 
  ; 
  

   diameter, 
  circa 
  1"5 
  mm. 
  Tiie 
  facet 
  slopes 
  in 
  accordance 
  

   with 
  the 
  general 
  asymmetry 
  of 
  the 
  tlieca. 
  Austin^s 
  fig. 
  2 
  a 
  

   shows 
  a 
  minute 
  lumen 
  and 
  a 
  finely 
  ridged 
  l)order. 
  

  

  BB 
  5 
  ; 
  1. 
  ant. 
  and 
  r. 
  post, 
  hexagonal 
  ; 
  in 
  post. 
  B 
  the 
  upper 
  

   angle 
  is 
  truncated 
  by 
  the 
  periproct; 
  in 
  1. 
  post, 
  and 
  r. 
  ant. 
  BB 
  

   the 
  lower 
  margins 
  meet 
  in 
  a 
  curve, 
  making 
  the 
  plates 
  penta- 
  

   gonal. 
  Post. 
  B 
  is 
  the 
  largest, 
  its 
  height 
  and 
  width 
  being 
  

   4*7 
  and 
  4*55 
  mm. 
  ; 
  r. 
  ant. 
  B 
  is 
  tlie 
  smallest, 
  its 
  height 
  and 
  

   width 
  being 
  4"3 
  and 
  3 
  mm. 
  

  

  RR 
  5, 
  in 
  general 
  form 
  more 
  or 
  less 
  shield-shaped, 
  but 
  

   variously 
  modified 
  and 
  unequal 
  in 
  size. 
  The 
  largest 
  is 
  

   1. 
  post. 
  11, 
  which 
  projects 
  upwards 
  higher 
  than 
  the 
  others, 
  

   with 
  its 
  shoulders 
  sloping 
  up 
  to 
  a 
  truncated 
  flattened 
  

   surface, 
  wliich 
  may 
  be 
  an 
  arm-facet 
  ; 
  on 
  its 
  right 
  side 
  this 
  

   radial 
  is 
  excavated 
  below 
  liy 
  the 
  peri|)roct. 
  Next 
  in 
  size 
  are 
  

   1. 
  ant. 
  B, 
  which 
  slopes 
  up 
  to 
  1. 
  post. 
  11, 
  and 
  r. 
  post. 
  R. 
  The 
  

   latter 
  on 
  its 
  left 
  side 
  is 
  excavated 
  below 
  by 
  the 
  periproct, 
  

   and 
  is 
  produced 
  above 
  so 
  as 
  to 
  arch 
  over 
  the 
  periproct 
  ; 
  in 
  

   this 
  region 
  either 
  it 
  meets 
  1. 
  post. 
  R 
  or 
  is 
  separated 
  from 
  that 
  

   plate 
  by 
  a 
  small 
  anal 
  plate 
  ; 
  1 
  rather 
  incline 
  to 
  the 
  latter 
  

   interpretation, 
  but 
  the 
  evidence 
  is 
  none 
  too 
  clear. 
  The 
  

   remaining 
  radials, 
  r. 
  ant. 
  R 
  and 
  ant. 
  R^ 
  were 
  still 
  smaller; 
  

   r. 
  ant. 
  R 
  is 
  broken 
  away, 
  but 
  its 
  outline 
  can 
  be 
  reconstructed 
  ; 
  

   it 
  was 
  probably 
  the 
  smallest 
  of 
  the 
  five. 
  Thus, 
  in 
  accordance 
  

   with 
  the 
  general 
  asymmetry, 
  there 
  is 
  a 
  slope 
  of 
  the 
  upper 
  

   surfaces 
  of 
  the 
  radials, 
  down 
  from 
  the 
  projecting 
  1, 
  post. 
  R 
  to 
  

   r. 
  ant. 
  IR. 
  

  

  The 
  brachial 
  facets 
  cannot 
  be 
  distinguished, 
  but, 
  as 
  seen 
  

   from 
  above 
  (tig. 
  1 
  b), 
  the 
  radials 
  bound 
  a 
  rather 
  irregular 
  

   opening, 
  to 
  which 
  an 
  angular 
  excavation 
  of 
  the 
  upper 
  margins 
  

   of 
  the 
  radials 
  tends 
  to 
  give 
  a 
  pentagonal 
  character. 
  Whether 
  

   in 
  the 
  living 
  state 
  this 
  was 
  covered 
  by 
  orals, 
  tegminals, 
  or 
  

   reduced 
  brachials 
  is 
  uncertain 
  ; 
  at 
  any 
  rate 
  it 
  was 
  uncovered 
  

   in 
  all 
  the 
  fossils 
  luiown 
  to 
  the 
  Austins, 
  and 
  this 
  fact 
  no 
  

   doubt 
  it 
  was 
  that 
  suggested 
  the 
  trivial 
  name 
  anapeptamenus 
  

   (lying 
  open), 
  in 
  distinction 
  to 
  claiisus. 
  

  

  In 
  considering 
  the 
  Relations 
  of 
  Sycocrinus 
  anapepta- 
  

   menus, 
  it 
  is 
  seen 
  at 
  once 
  that 
  they 
  are 
  very 
  close 
  to 
  

   " 
  Hypocrimcs" 
  piriformis, 
  and 
  thus 
  far 
  my 
  former 
  suggested 
  

   reference 
  of 
  this 
  British 
  species 
  to 
  Hi/pocrirms 
  is 
  confirmed. 
  

   I 
  have, 
  however, 
  recently 
  shown 
  that 
  H. 
  piriformis 
  is 
  no 
  

   Hypocrinus 
  but 
  a 
  Taxocrinid 
  (Proc 
  Zool. 
  Soc. 
  1913, 
  p. 
  910). 
  

   The 
  diflerence 
  between 
  it 
  and 
  S. 
  anapeptainenus 
  lies 
  essenti- 
  

   ally 
  in 
  the 
  greater 
  size 
  of 
  the 
  right 
  posterior 
  radial 
  in 
  the 
  

  

  