﻿268 
  C. 
  E. 
  Beecher 
  — 
  Uintacrinus 
  from 
  Kansas. 
  

  

  Most 
  of 
  the 
  specimens 
  are 
  lying 
  on 
  the 
  side 
  with 
  the 
  arms 
  

   extended 
  ventrally 
  in 
  a 
  plumose 
  manner. 
  A 
  considerable 
  

   number, 
  however, 
  present 
  the 
  basal 
  aspect 
  of 
  the 
  calyx, 
  and 
  in 
  

   this 
  position 
  the 
  arm-branches 
  belonging 
  to 
  a 
  particular 
  indi- 
  

   vidual 
  can 
  rarely 
  be 
  observed, 
  since 
  they 
  seem 
  to 
  penetrate 
  

   below 
  the 
  surface 
  of 
  the 
  slab 
  and 
  lie 
  in 
  another 
  plane. 
  It 
  will 
  

   be 
  seen 
  that 
  the 
  calyces 
  lying 
  on 
  their 
  sides 
  point 
  in 
  all 
  direc- 
  

   tions 
  in 
  the 
  plane 
  of 
  the 
  slab, 
  though 
  a 
  considerable 
  number 
  

   have 
  their 
  arm-branches 
  extended 
  toward 
  the 
  upper 
  edge 
  of 
  

   the 
  slab 
  as 
  it 
  now 
  stands. 
  This 
  could 
  indicate 
  at 
  the 
  most 
  but 
  

   an 
  extremely 
  gentle 
  current, 
  and 
  the 
  presence 
  of 
  several 
  small 
  

   oysters 
  (Ostrea 
  larva 
  Lam.) 
  tends 
  to 
  show 
  that 
  the 
  water 
  was 
  

   of 
  moderate 
  depth. 
  

  

  Two 
  slightly 
  diverging 
  grooves 
  in 
  the 
  surface 
  of 
  the 
  slab 
  at 
  

   the 
  right, 
  below 
  the 
  middle, 
  suggest 
  the 
  mold 
  of 
  an 
  object 
  like 
  

   a 
  Baculite, 
  but 
  as 
  no 
  vestige 
  of 
  shell 
  is 
  preserved, 
  it 
  may 
  be 
  

   an 
  accidental 
  feature. 
  

  

  Nearly 
  all 
  the 
  specimens 
  of 
  Uintacrinus, 
  as 
  well 
  as 
  the 
  

   limestone 
  layer 
  containing 
  them, 
  are 
  of 
  a 
  light 
  buff 
  color, 
  

   while 
  the 
  slight 
  coating 
  of 
  shaly 
  matter 
  is 
  also 
  light 
  in 
  hue, 
  

   sometimes 
  of 
  a 
  bluish 
  tint, 
  so 
  that 
  the 
  contrast 
  between 
  the 
  

   fossils 
  and 
  the 
  matrix 
  is 
  not 
  strongly 
  marked. 
  This 
  defect 
  has 
  

   been 
  obviated 
  by 
  painting 
  the 
  entire 
  slab 
  with 
  a 
  mixture 
  of 
  

   gum-water 
  and 
  ivory 
  black, 
  which 
  penetrated 
  and 
  adhered 
  to 
  

   the 
  shaly 
  and 
  weathered 
  surface 
  of 
  the 
  limestone, 
  but 
  was 
  

   easily 
  washed 
  from 
  the 
  calyces 
  and 
  arm-branches 
  of 
  the 
  cri- 
  

   noids. 
  This 
  treatment 
  has 
  rendered 
  the 
  slab 
  an 
  object 
  of 
  

   great 
  beauty, 
  with 
  its 
  medusae-form 
  crinoids 
  and 
  the 
  delicate 
  

   tracery 
  of 
  the 
  arm-branches 
  against 
  the 
  dark 
  background. 
  

  

  Tale 
  University 
  Museum, 
  New 
  Haven, 
  Conn., 
  February 
  10, 
  1900. 
  

  

  EXPLANATION 
  OF 
  PLATES. 
  

  

  Plate 
  III. 
  — 
  Slab 
  of 
  Uintacrinus 
  socialis 
  Grinnell, 
  containing 
  two 
  hundred 
  and 
  

  

  twenty 
  individuals. 
  Size 
  6 
  ft. 
  1 
  in. 
  (2 
  m 
  ) 
  by 
  4 
  ft. 
  6| 
  in. 
  (l 
  m 
  38 
  cm 
  ). 
  

  

  Niobrara 
  Chalk. 
  Near 
  Elkader, 
  Logan 
  County, 
  Kansas. 
  

  

  Presented 
  to 
  Yale 
  University 
  Museum 
  by 
  Professor 
  0. 
  C. 
  Marsh. 
  

  

  Collected 
  by 
  H. 
  T. 
  Martin. 
  

   Plate 
  IV. 
  — 
  A 
  portion 
  of 
  the 
  same 
  slab 
  on 
  a 
  larger 
  scale. 
  

  

  