﻿6 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  67 
  

  

  The 
  set 
  of 
  arms 
  shown 
  in 
  the 
  Black 
  Island 
  specimen 
  (fig. 
  1) 
  

   are 
  also 
  clearly 
  of 
  the 
  sub 
  angular 
  is 
  type. 
  The 
  brachials 
  are 
  slightly 
  

   wedge-shaped, 
  giving 
  off 
  a 
  pinnule 
  from 
  the 
  longer 
  side 
  of 
  each, 
  

   both 
  on 
  the 
  main 
  arms 
  and 
  the 
  ramules, 
  so 
  that 
  as 
  seen 
  from 
  either 
  

   margin 
  the 
  pinnules 
  are 
  borne 
  alternately 
  on 
  every 
  second 
  brachial. 
  

   Their 
  form 
  and 
  proportions, 
  as 
  well 
  as 
  the 
  exquisite 
  delineation 
  of 
  

   details, 
  are 
  clearly 
  brought 
  out 
  in 
  the 
  photograph. 
  One 
  notable 
  

   item 
  is 
  the 
  very 
  large 
  size 
  of 
  the 
  first 
  pinnular. 
  which 
  articulates 
  

   with 
  two 
  brachials. 
  Some 
  of 
  the 
  pinnulars 
  show 
  notches 
  or 
  crenu- 
  

   lations 
  on 
  the 
  ventral 
  edges. 
  

  

  In 
  size 
  there 
  is 
  not 
  much 
  difference 
  between 
  our 
  specimens 
  and 
  

   the 
  average 
  of 
  those 
  from 
  Wurtemburg. 
  Compared 
  with 
  good- 
  

   sized 
  specimens 
  from 
  Holzmaden, 
  as 
  figured 
  in 
  Quenstedt, 
  11 
  we 
  

   have 
  the 
  following 
  details 
  : 
  

  

  With 
  the 
  foregoing 
  facts 
  to 
  go 
  on, 
  there 
  would 
  seem 
  to 
  be 
  no 
  good 
  

   reason 
  for 
  separating 
  the 
  Alaskan 
  form 
  specifically 
  from 
  subangu- 
  

   laris. 
  Yet 
  in 
  order 
  to 
  allow 
  for 
  probable 
  migrational 
  changes 
  not 
  

   disclosed 
  by 
  our 
  incomplete 
  material, 
  and 
  for 
  more 
  convenient 
  des- 
  

   ignation 
  in 
  the 
  literature, 
  I 
  think 
  best 
  to 
  give 
  it 
  a 
  varietal 
  name, 
  

   Pentacrinus 
  subangularis, 
  var. 
  alaska, 
  which 
  will 
  have 
  at 
  least 
  as 
  

   good 
  ground 
  to 
  stand 
  on 
  as 
  any 
  of 
  the 
  five 
  varieties 
  based 
  on 
  Wur- 
  

   temburg 
  specimens 
  into 
  which 
  Quenstedt 
  undertook 
  to 
  subdivide 
  

   the 
  species 
  P. 
  briareus, 
  to 
  say 
  nothing 
  of 
  the 
  doubt, 
  before 
  mentioned, 
  

   whether 
  the 
  type 
  of 
  the 
  (briareus) 
  fossills 
  group 
  occurs 
  in 
  that 
  area. 
  

  

  Wishing 
  to 
  have 
  the 
  benefit 
  of 
  the 
  fullest 
  information 
  before 
  

   finally 
  recording 
  my 
  own 
  impression. 
  I 
  sent 
  copies 
  of 
  my 
  figures 
  to 
  

   Dr. 
  F. 
  A. 
  Bather, 
  requesting 
  him 
  to 
  compare 
  them 
  with 
  the 
  speci- 
  

   mens 
  in 
  the 
  British 
  Museum, 
  and 
  to 
  favor 
  me 
  Avith 
  his 
  opinion. 
  

   This 
  he 
  has 
  very 
  kindly 
  done, 
  and 
  given 
  me 
  a 
  report 
  from 
  which 
  I 
  

   quote 
  the 
  following 
  extract: 
  

  

  London, 
  25 
  May, 
  1923. 
  

  

  Dear 
  Mr. 
  Springer: 
  I 
  have 
  examined 
  your 
  photographs 
  of 
  Pentacrinus 
  from 
  

   Alaska 
  with 
  great 
  care, 
  comparing 
  them 
  with 
  the 
  published 
  descriptions, 
  and 
  

   with 
  the 
  material 
  in 
  this 
  museum 
  from 
  Dorset 
  and 
  Wurtemberg. 
  The 
  only- 
  

   difference 
  I 
  can 
  see 
  is 
  that 
  the 
  few 
  stem 
  fragments 
  visible 
  from 
  the 
  side 
  do 
  

   not 
  show 
  such- 
  marked 
  or 
  regular 
  alternation 
  in 
  the 
  sizes 
  of 
  the 
  columnals 
  as 
  

   do 
  all 
  the 
  specimens 
  in 
  this 
  museum. 
  This 
  may 
  depend 
  possibly 
  on 
  the 
  region 
  

   of 
  the 
  column 
  from 
  which 
  they 
  came, 
  and 
  in 
  any 
  case 
  the 
  evidence 
  of 
  the 
  

   photograph 
  is 
  not 
  very 
  extensive.. 
  The 
  photograph 
  of 
  the 
  arms 
  shows 
  the 
  

  

  "Petref. 
  Deutschl., 
  vol. 
  4, 
  pi. 
  101. 
  

  

  