﻿PLATE 
  XXV. 
  

  

  Meristina 
  tflTIDA 
  Hall. 
  

  

  Page 
  160. 
  

  

  Fig. 
  1. 
  Dorsal 
  view 
  of 
  a 
  small 
  specimen 
  of 
  a 
  rounded 
  form. 
  

  

  Fig. 
  2. 
  Ventral 
  view 
  of 
  a 
  rhomboidal 
  specimen 
  which 
  is 
  emarginate 
  in 
  front. 
  

  

  Fig. 
  3. 
  Dorsal 
  view 
  of 
  a 
  large, 
  broadly 
  ovate 
  form, 
  which 
  is 
  emarginate 
  in 
  front 
  

  

  and 
  shows 
  the 
  foramen 
  in 
  the 
  beak. 
  

   Fig. 
  4. 
  Ventral 
  view 
  of 
  a 
  large 
  rhomboid-ovate 
  specimen, 
  which 
  is 
  strongly 
  

  

  emarginate 
  in 
  front. 
  

   Fig. 
  5. 
  Lateral 
  view 
  of 
  the 
  specimen 
  fig. 
  3, 
  showing 
  the 
  convexity 
  of 
  the 
  valves. 
  

   Fig. 
  6. 
  Dorsal 
  view 
  of 
  a 
  narrow, 
  elongate-ovate 
  form, 
  with 
  a 
  slight 
  emargination 
  

  

  in 
  front. 
  

   Fig. 
  7. 
  Dorsal 
  view 
  of 
  a 
  narrow, 
  rhomboidal 
  form, 
  which 
  is 
  not 
  emarginate. 
  

  

  Figs. 
  3, 
  5, 
  6 
  and 
  7 
  are 
  copied 
  from 
  Pal., 
  N. 
  Y., 
  Vol. 
  IV, 
  Pt. 
  II: 
  Re- 
  

   vision 
  of 
  the 
  Brachiopoda, 
  (unpublished). 
  

  

  Meristina 
  Maria 
  Hall. 
  

   Page 
  159. 
  

  

  Fig. 
  8. 
  Dorsal 
  view 
  of 
  a 
  young 
  specimen 
  which 
  has 
  not 
  begun 
  to 
  develop 
  the 
  

   mesial 
  elevation 
  or 
  sinus, 
  and 
  is 
  proportionally 
  broader 
  than 
  the 
  

   mature, 
  full-grown 
  specimens. 
  

  

  Figs. 
  9, 
  10. 
  Dorsal 
  and 
  front 
  views 
  of 
  a 
  large 
  mature 
  specimen. 
  

  

  Fig. 
  11. 
  Front 
  view 
  of 
  a 
  specimen 
  with 
  the 
  mesial 
  fold 
  much 
  less 
  strongly 
  

   marked 
  than 
  fig. 
  10. 
  

  

  Fig. 
  12. 
  Lateral 
  view 
  of 
  the 
  specimen 
  fig. 
  9. 
  

  

  Retzia 
  evax 
  Hall. 
  

   Page 
  160. 
  

  

  Figs. 
  13-17. 
  Dorsal 
  views 
  of 
  specimens 
  varying 
  in 
  size 
  and 
  form, 
  and 
  exhibiting 
  

   some 
  of 
  the 
  phases 
  which 
  mark 
  the 
  species 
  in 
  its 
  advanced 
  stages 
  

   of 
  growth. 
  

  

  Fig. 
  18. 
  Profile 
  of 
  the 
  specimen 
  fig. 
  14, 
  showing 
  the 
  convexity 
  of 
  the 
  valves. 
  

  

  Fig. 
  19 
  . 
  Ventral 
  view 
  of 
  a 
  specimen 
  showing 
  the 
  mesial 
  depression. 
  

  

  Fig. 
  20. 
  Front 
  view 
  of 
  the 
  specimen 
  figs. 
  14 
  and 
  18, 
  showing 
  the 
  depth 
  of 
  the 
  

  

  depression. 
  

   Fig. 
  21. 
  Ventral 
  view 
  of 
  a 
  small, 
  elongate 
  form, 
  showing 
  finer 
  plications 
  — 
  

  

  apparently 
  a 
  mature 
  specimen. 
  

  

  NlJCLEOSPIRA 
  PISIFORMIS 
  Hall. 
  

  

  Page 
  160. 
  

  

  Figs. 
  22-25. 
  Dorsal, 
  ventral, 
  lateral 
  and 
  cardinal 
  views 
  of 
  a 
  ventricose 
  specimen, 
  

   having 
  much 
  the 
  appearance 
  of 
  N. 
  ventricosa 
  of 
  the 
  Lower 
  Helder- 
  

   berg 
  group. 
  

  

  