﻿Vol. 
  53.] 
  OF 
  THE 
  CHALK 
  ROCK. 
  403 
  

  

  since 
  they 
  do 
  not 
  live 
  in 
  water 
  of 
  less 
  than 
  95 
  fathoms 
  in. 
  depth 
  ; 
  

   they 
  are 
  abundant 
  between 
  95 
  and 
  200 
  fathoms, 
  and 
  also 
  from 
  301 
  

   to 
  700 
  fathoms. 
  1 
  

  

  EXPLANATION 
  OF 
  PLATES 
  XXVII. 
  & 
  XXVIII. 
  

  

  All 
  the 
  specimens 
  figured 
  come 
  from 
  the 
  Chalk 
  Rock, 
  and, 
  unless 
  otherwise 
  

   stated, 
  are 
  preserved 
  in 
  the 
  Woodwardian 
  Museum 
  (Montagu 
  Smith 
  Collection). 
  

   The 
  figures 
  are 
  of 
  the 
  natural 
  size, 
  except 
  where 
  otherwise 
  stated. 
  

  

  Plate 
  XXVII. 
  

  

  Figs. 
  1 
  & 
  2. 
  Nncula 
  sp. 
  Internal 
  moulds. 
  

  

  Fig. 
  3. 
  Area 
  sp., 
  cf. 
  Galliennei, 
  d'Orbigny. 
  Internal 
  mould. 
  

  

  4. 
  Area 
  sp. 
  Internal 
  mould. 
  

   Figs. 
  5 
  & 
  6. 
  Area 
  (Barbatia) 
  sp., 
  cf. 
  Geinitzi, 
  Eeuss. 
  5. 
  Wax 
  mould 
  of 
  exterior 
  

  

  showing 
  ornamentation. 
  5 
  a. 
  Portion 
  of 
  same, 
  x5. 
  6. 
  Internal 
  

  

  mould. 
  

   Figs. 
  7 
  & 
  8. 
  Limopsis 
  sp. 
  Internal 
  moulds. 
  X 
  1^. 
  

   Figs. 
  9-12. 
  Modiola 
  Cottee, 
  Bonier. 
  9, 
  10. 
  From 
  Winchester 
  (coll. 
  B. 
  M. 
  

  

  Brydone). 
  11. 
  Part 
  of 
  a 
  larger 
  specimen 
  from 
  Luton 
  (collected 
  

  

  by 
  the 
  Author). 
  11 
  a. 
  Portion 
  of 
  shell 
  of 
  the 
  same 
  enlarged, 
  showing 
  

  

  the 
  character 
  of 
  the 
  ornamentation, 
  x 
  6. 
  12. 
  Outline 
  of 
  section 
  of 
  

  

  •valve 
  of 
  the 
  same 
  specimen. 
  

   Fig. 
  13. 
  Inoceramus 
  striatus, 
  Mantell. 
  

  

  Figs. 
  14-17. 
  Inoceramus 
  sp. 
  Internal 
  moulds. 
  15. 
  Posterior 
  view 
  of 
  14. 
  

   Figs. 
  18 
  & 
  19. 
  Plicatula 
  Barroisi, 
  Peron, 
  from 
  Winchester 
  (coll. 
  B. 
  M. 
  Brydone). 
  

  

  X2. 
  

   Figs. 
  20-22. 
  Cardiam 
  turoniense, 
  sp. 
  nov. 
  20. 
  Wax 
  mould, 
  X 
  1^. 
  20 
  a. 
  Portion 
  

  

  of 
  same 
  further 
  enlarged, 
  showing 
  the 
  character 
  of 
  the 
  ornamentation, 
  

  

  X5. 
  21. 
  Natural 
  mould, 
  Xl^. 
  22. 
  Anterior 
  view 
  of 
  the 
  same, 
  

  

  Xlf- 
  

   Figs. 
  23 
  & 
  24. 
  Cardium, 
  cf. 
  cenomanense, 
  d'Orbigny. 
  Internal 
  mould. 
  

  

  21. 
  Anterior 
  view. 
  

   Fig. 
  25. 
  Arctica 
  quadrata 
  (d'Orbigny). 
  Anterior 
  view 
  of 
  natural 
  mould. 
  

  

  Morgan's 
  Hill, 
  near 
  Devizes 
  (coll. 
  A. 
  J. 
  Jukes-Browne). 
  

  

  Plate 
  XXVIII. 
  

  

  Fig. 
  1. 
  Arctica 
  quadrata 
  (d'Orbigny). 
  Bight 
  valve. 
  

  

  Figs. 
  2-5. 
  Cardita 
  cancellata, 
  sp. 
  nov. 
  2. 
  Wax 
  mould. 
  3. 
  Portion 
  of 
  same, 
  

  

  X 
  5. 
  4, 
  5. 
  Natural 
  mould. 
  4. 
  Anterior 
  view. 
  5. 
  Left 
  valve. 
  

   Figs. 
  6-8. 
  ArcHca 
  ? 
  equisulcata, 
  sp. 
  nov. 
  6. 
  Dorsal 
  view 
  of 
  natural 
  mould. 
  

  

  7. 
  Bight 
  valve 
  of 
  same. 
  8. 
  Left 
  valve, 
  with 
  part 
  of 
  shell 
  preserved. 
  

  

  8 
  a. 
  Portion 
  of 
  same 
  enlarged, 
  X 
  3. 
  

   Figs. 
  9 
  & 
  10. 
  Trapezium 
  trapezoidale 
  (Bomer). 
  9. 
  Left 
  valve. 
  10. 
  Dorsal 
  

  

  surface 
  of 
  the 
  two 
  valves. 
  

   Figs. 
  11 
  & 
  12 
  Trapezium 
  rectangulare, 
  sp. 
  nov. 
  Internal 
  moulds. 
  11. 
  Left 
  

  

  valve. 
  12. 
  Dorsal 
  surface 
  of 
  the 
  two 
  valves. 
  

   Figs. 
  13 
  & 
  14. 
  Corbis? 
  Morisoni, 
  sp. 
  nov. 
  13. 
  Bight 
  valve. 
  14. 
  Anterior 
  end. 
  

   Figs. 
  15-18. 
  Martesia? 
  rotunda 
  (Sowerby). 
  15-17. 
  Internal 
  casts, 
  X 
  2. 
  

  

  15. 
  Dorsal 
  view. 
  16. 
  Bight 
  valve. 
  17. 
  Anterior 
  end. 
  18. 
  Wax 
  

  

  mould 
  of 
  exterior 
  of 
  right 
  valve, 
  x2£. 
  

   Figs. 
  19 
  & 
  20. 
  Cuspidaria 
  caudata 
  (Nilsson). 
  Internal 
  cast. 
  19. 
  Left 
  valve. 
  

  

  20. 
  Dorsal 
  surface. 
  

  

  1 
  F. 
  E. 
  Schultze, 
  ' 
  Beport 
  on 
  Hexactinellida,' 
  Challenqer 
  Exped. 
  (1887) 
  

   pp. 
  453-467. 
  

  

  