﻿82 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol.67 
  

  

  REPTOCLAUSA 
  DENTICULATA, 
  new 
  species 
  

  

  Plate 
  18, 
  fig. 
  1 
  

  

  Description. 
  — 
  The 
  zoarium 
  creeps 
  over 
  shells 
  in 
  fronds 
  branching 
  

   at 
  a 
  right 
  angle. 
  The 
  tubes 
  are 
  arranged 
  on 
  each 
  side 
  of 
  the 
  median 
  

   crest 
  in 
  transverse 
  rows. 
  There 
  are 
  two 
  tubes 
  in 
  each 
  row; 
  the 
  peri- 
  

   stomes 
  are 
  denticulated 
  and 
  nonadjacent. 
  All 
  the 
  branches 
  are 
  sur- 
  

   rounded 
  by 
  a 
  more 
  or 
  less 
  broad 
  foliaceous 
  expansion 
  formed 
  of 
  

   aborted 
  tubes. 
  

  

  Measurements. 
  — 
  Diameter 
  of 
  peristomes, 
  0.16 
  mm.; 
  maximum 
  

   diameter 
  of 
  branches, 
  1 
  mm. 
  

  

  Affinities. 
  — 
  In 
  its 
  zoarial 
  simplicity 
  this 
  species 
  much 
  resembles 
  

   Idmonea 
  alipes 
  Gregory, 
  1899, 
  but 
  differs 
  in 
  its 
  denticulate 
  peristomes. 
  

  

  Occurrence. 
  — 
  Lower 
  Cretaceous 
  (Aptian) 
  : 
  Faringdon, 
  England. 
  

  

  Holotype.— 
  Cat. 
  No. 
  69936, 
  U.S.N.M. 
  

  

  REPTOCLAUSA 
  HAGENOWI 
  Sharpe, 
  1854 
  

  

  Plate 
  18, 
  figs. 
  2-5 
  

  

  1899. 
  Idmonea 
  hagenoici 
  Gregory, 
  Catalogue 
  of 
  the 
  Cretaceous 
  Bryozoa 
  in 
  the 
  

   British 
  Museum, 
  vol. 
  1, 
  p. 
  152, 
  pi. 
  8, 
  fig. 
  1. 
  (Bibliography.) 
  

  

  Structure. 
  — 
  We 
  have 
  been 
  able 
  to 
  make 
  some 
  sections 
  of 
  this 
  spe- 
  

   cies. 
  In 
  transverse 
  section 
  through 
  a 
  fascicle 
  the 
  tubes 
  are 
  rounded, 
  

   and 
  in 
  the 
  vicinity 
  of 
  the 
  crest 
  they 
  are 
  surrounded 
  by 
  a 
  strong 
  

   solid 
  epitheca. 
  In 
  longitudinal 
  section 
  the 
  tubes 
  are 
  short, 
  oblique, 
  

   club-shaped; 
  the 
  crest 
  is 
  a 
  thickened 
  continuous 
  epitheca. 
  

  

  On 
  the 
  fascicles 
  the 
  tubes 
  are 
  arranged 
  in 
  quincunx; 
  the 
  peri- 
  

   stomes 
  are 
  orbicular 
  and 
  somewhat 
  salient 
  and 
  their 
  diameter 
  is 
  

   larger 
  in 
  the 
  vicinity 
  of 
  the 
  crest 
  of 
  the 
  fascicles. 
  

  

  Occurrence. 
  — 
  Lower 
  Cretaceous: 
  Faringdon, 
  England 
  (Aptian); 
  

   Villers-le-Lac 
  (Doubs) 
  , 
  France 
  (Valangian). 
  

  

  Plesiotype.— 
  Cat. 
  No. 
  69937, 
  U.S.N.M. 
  

  

  REPTOCLAUSA 
  MEANDRINA 
  De 
  Loriol, 
  1868 
  

  

  Plate 
  18, 
  figs. 
  6-8 
  

  

  1868. 
  Reptoclausa 
  meandrina 
  De 
  Loriol, 
  Valanginien 
  d" 
  Arzier, 
  Paleontologie 
  

   Suisse, 
  Liv. 
  4, 
  p. 
  62, 
  pi. 
  6, 
  fig. 
  1. 
  

  

  The 
  zoarium 
  encrusts 
  Terebratulas 
  and 
  oyster 
  shells. 
  The 
  peri- 
  

   stomes 
  are 
  wider 
  than 
  in 
  Reptoclausa 
  Jiagenowi 
  and 
  the 
  fascicles 
  are 
  

   arranged 
  much 
  more 
  irregularly. 
  The 
  interfascicular 
  tubules 
  are 
  

   often 
  visible 
  exteriorly. 
  We 
  have 
  found 
  beautiful 
  specimens 
  in 
  our 
  

   collections. 
  

  

  Occurrence. 
  — 
  Lower 
  Cretaceous 
  (Valangian) 
  : 
  Sainte-Croix 
  and 
  

   D' 
  Arzier, 
  Switzerland. 
  

  

  Plesiotype.— 
  Cat. 
  No. 
  69938, 
  U.S.N.M. 
  

  

  