﻿22 
  

  

  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  

  

  Measurements. 
  — 
  Diameter 
  of 
  apertures, 
  0.10 
  mm.; 
  maximum 
  

   zoarial 
  width, 
  9 
  mm.; 
  zoarial 
  height, 
  14 
  mm. 
  

  

  Structure. 
  — 
  The 
  zoarial 
  form 
  is 
  rather 
  constant, 
  ovoid 
  or 
  fusiform. 
  

   On 
  the 
  base, 
  viewed 
  from 
  below, 
  the 
  tubes 
  are 
  arranged 
  fan-shape 
  

   in 
  the 
  manner 
  of 
  Berenicea. 
  

  

  Many 
  of 
  the 
  zoaria 
  appear 
  to 
  be 
  formed 
  of 
  many 
  lamellae 
  inserted 
  

   one 
  on 
  the 
  other. 
  In 
  reality 
  thin 
  sections 
  show 
  that 
  this 
  is 
  not 
  so 
  

   for 
  there 
  are 
  no 
  successive 
  complete 
  basal 
  lamellae; 
  sometimes 
  the 
  

  

  Fio. 
  6,— 
  Ceriopora 
  ovoidca, 
  new 
  species. 
  B. 
  Meridian 
  section 
  of 
  another 
  zoarium, 
  X 
  16, 
  in 
  which 
  the 
  zonal 
  

   lines 
  have 
  been 
  transformed 
  into 
  basal 
  lamellae. 
  The 
  main 
  zoarial 
  tubes 
  are 
  oriented 
  in 
  a 
  different 
  

   direction 
  from 
  those 
  of 
  the 
  primitive 
  zoarium. 
  Lower 
  Cretaceous 
  (Valangian): 
  Sainte-Croix, 
  Switzer- 
  

   land 
  

  

  zonal 
  lines 
  are 
  transformed 
  into 
  basal 
  lamellae 
  but 
  only 
  along 
  a 
  part 
  

   of 
  their 
  course. 
  This 
  is 
  an 
  arrangement 
  intermediate 
  between 
  that 
  

   of 
  Ceriopora 
  and 
  of 
  typical 
  Reptomulticava, 
  so 
  that 
  we 
  do 
  not 
  know 
  

   into 
  which 
  genus 
  this 
  species 
  as 
  well 
  as 
  most 
  of 
  the 
  following 
  should 
  

   be 
  placed. 
  

  

  The 
  'tubes 
  are 
  cylindrical, 
  with 
  concave 
  diaphragms 
  and 
  with 
  

   peripheral 
  gemmation. 
  The 
  walls 
  are 
  rather 
  thick, 
  moniliform 
  in 
  

   a 
  part 
  of 
  their 
  course, 
  and 
  formed 
  of 
  two 
  rows 
  of 
  vesicles 
  in 
  their 
  

  

  