﻿PLATE 
  XVI. 
  

  

  EUCALYPTOCEINUS 
  C^ELATUS 
  Hall. 
  

  

  Page 
  142. 
  

  

  Fig. 
  1. 
  A 
  young 
  individual 
  enlarged 
  to 
  three 
  diameters. 
  The 
  divisions 
  of 
  the 
  

   arm-plates 
  are 
  incorrectly 
  represented. 
  

  

  Fig. 
  2. 
  A 
  larger 
  individual 
  preserving 
  the 
  arms 
  in 
  place, 
  but 
  the 
  divisions 
  of 
  

   the 
  arm-plates 
  are 
  not 
  fully 
  shown 
  in 
  the 
  figure. 
  

  

  Fig. 
  3. 
  Lateral 
  view 
  of 
  the 
  calyx 
  of 
  a 
  full-grown 
  individual, 
  of 
  the 
  prevailing 
  

   form. 
  

  

  Fig. 
  4. 
  Basal 
  view 
  of 
  the 
  same. 
  

  

  Fig. 
  5. 
  A 
  lateral 
  view 
  of 
  a 
  specimen 
  showing 
  the 
  calyx 
  and 
  the 
  solid 
  interbrachial 
  

   plates 
  of 
  one 
  side. 
  

  

  Fig. 
  6. 
  The 
  opposite 
  side 
  of 
  the 
  same 
  specimen, 
  which 
  is 
  broken 
  so 
  as 
  to 
  reveal 
  

   the 
  visceral 
  cavity, 
  above 
  which 
  are 
  the 
  interior 
  dome 
  plates, 
  cov- 
  

   ering 
  the 
  canal 
  leading 
  to 
  the 
  exterior. 
  These 
  anchylosed 
  plates 
  

   are 
  embraced 
  and 
  supported 
  by 
  the 
  inner 
  edges 
  of 
  the 
  interbrachial 
  

   plates, 
  as 
  shown 
  in 
  the 
  figure. 
  

  

  Fig. 
  7. 
  The 
  summit 
  of 
  the 
  same 
  specimen, 
  showing 
  the 
  interbrachial 
  plates, 
  and 
  

   the 
  accessory 
  plates, 
  surrounding 
  the 
  orifice 
  at 
  the 
  summit. 
  The 
  

   upper 
  side 
  of 
  the 
  figure, 
  where 
  the 
  exterior 
  is 
  broken 
  away, 
  shows 
  

   distinctly 
  the 
  bases 
  of 
  two 
  interbrachial 
  plates, 
  and 
  the 
  projecting 
  

   angles 
  of 
  the 
  interior 
  dome 
  plates. 
  

  

  Fig. 
  8. 
  The 
  upper 
  margin 
  and 
  interior 
  of 
  a 
  calyx, 
  showing 
  the 
  plates 
  and 
  cica- 
  

   trices 
  for 
  the 
  attachment 
  of 
  the 
  arms 
  and 
  interbrachial 
  plates. 
  

  

  Figs. 
  9, 
  10. 
  Interior 
  and 
  lateral 
  views 
  of 
  the 
  basal 
  and 
  subradial 
  plates 
  of 
  the 
  

  

  species, 
  showing 
  the 
  division 
  of 
  the 
  basal 
  plates, 
  as 
  seen 
  on 
  the 
  

  

  inner 
  side, 
  and 
  their 
  great 
  development 
  in 
  the 
  interior 
  of 
  the 
  calyx. 
  

  

  These 
  are 
  rarely 
  distinguishable 
  within 
  the 
  column 
  cavity, 
  and 
  

  

  probably 
  never 
  on 
  the 
  exterior 
  surface. 
  

  

  ICHTHYOCRIKUS 
  SUBANGULARIS 
  Hall. 
  

   Page 
  137. 
  

  

  Figs. 
  11, 
  12. 
  Lateral 
  and 
  basal 
  views 
  of 
  a 
  fragment, 
  showing 
  subradial 
  and 
  radial 
  

   plates 
  with 
  a 
  decided 
  pentangular 
  outline. 
  

  

  Fig. 
  13. 
  Lateral 
  view 
  of 
  a 
  larger 
  fragment, 
  showing 
  the 
  rays 
  to 
  near 
  the 
  third 
  

   division 
  on 
  two 
  of 
  the 
  series, 
  and 
  a 
  less 
  decided 
  subangularity 
  of 
  

   the 
  body 
  in 
  the 
  lower 
  parts 
  than 
  the 
  preceding 
  specimen. 
  

  

  

  