﻿Plate 
  17 
  

  

  Page 
  

   Figs. 
  1—5. 
  Leiosoecia 
  constanti 
  D'Orbigny, 
  1850 
  77 
  

  

  1. 
  Two 
  fragments, 
  natural 
  size. 
  

   2, 
  3. 
  A 
  mammillated 
  specimen, 
  X12 
  and 
  X25, 
  showing 
  the 
  

   polygonal 
  orifices 
  and 
  the 
  small 
  mesopores. 
  

  

  4. 
  Portion 
  of 
  an 
  ovicelled 
  branch 
  with 
  large 
  mesopores, 
  

  

  X12. 
  

  

  5. 
  Surface, 
  X12, 
  with 
  large 
  mesopores 
  and 
  showing 
  a 
  cir- 
  

  

  cular 
  area 
  of 
  mesopores. 
  

   Lower 
  Cretaceous 
  (Valangian) 
  : 
  Sainte-Croix, 
  Switzer- 
  

   land. 
  

  

  Figs. 
  6, 
  7. 
  ( 
  'lausa 
  cram 
  <, 
  new 
  species 
  79 
  

  

  G. 
  Young 
  zoarium, 
  X12, 
  with 
  the 
  peristomes 
  arranged 
  in 
  

  

  transverse 
  rows. 
  

   7. 
  Same 
  zoarium, 
  X25. 
  Extremity 
  showing 
  tubes 
  of 
  the 
  

   same 
  size 
  and 
  revealing 
  peripheral 
  gemmation. 
  

   Lower 
  Cretaceous 
  (Aptian) 
  : 
  Faringdon, 
  England. 
  

  

  Fins. 
  8-11. 
  Clausa 
  zonifera, 
  new 
  species 
  80 
  

  

  8, 
  9. 
  Specimens, 
  natural 
  size 
  and 
  several 
  X2. 
  

  

  10. 
  Young 
  zoarium, 
  X12, 
  showing 
  the 
  zones 
  of 
  dactyl- 
  

  

  ethrae. 
  

  

  11. 
  Same 
  specimen, 
  X25, 
  illustrating 
  the 
  arrangement 
  

  

  of 
  dactylethrae 
  around 
  the 
  orifices. 
  

   Lower 
  Cretaceous 
  (Aptian): 
  Faringdon, 
  England. 
  

   Figs. 
  12-15. 
  Leiosoecia 
  proximo,, 
  new 
  species 
  79 
  

  

  12. 
  Zoarial 
  fragments, 
  natural 
  size. 
  

  

  13. 
  Specimen 
  with 
  convex 
  ovicell, 
  X12. 
  

  

  14. 
  Specimen 
  with 
  ovicell 
  little 
  convex, 
  X12. 
  

  

  15. 
  Surface, 
  X25. 
  

  

  Lower 
  Cretaceous 
  (Valangian): 
  Sainte-Croix, 
  Swit- 
  

   zerland. 
  

   110 
  

  

  