﻿CYCLOSTOMATOUS 
  BRYOZOA 
  CANU 
  AND 
  BASSLER 
  

  

  69 
  

  

  The 
  longitudinal 
  section 
  of 
  the 
  extremity 
  of 
  a 
  young 
  branch 
  

   shows 
  the 
  disappearance 
  of 
  the 
  central 
  bundles 
  of 
  tubes, 
  the 
  latter 
  

   expanding 
  in 
  fan-shape 
  around 
  the 
  zoarial 
  axis. 
  A 
  longitudinal 
  

   section 
  made 
  through 
  a 
  branch 
  with 
  facettes 
  was 
  not 
  very 
  success- 
  

   ful, 
  as 
  silicification 
  had 
  invaded 
  the 
  tubes 
  of 
  the 
  exterior 
  lamella. 
  

   The 
  peristomes 
  were 
  arranged 
  in 
  quincunx 
  and 
  the 
  tube 
  appeared 
  

   with 
  thickened 
  walls 
  without 
  any 
  of 
  them 
  having 
  been 
  sectioned 
  

   tangentially. 
  In 
  transverse 
  section 
  the 
  central 
  bundle 
  is 
  quite 
  

   apparent. 
  

  

  Fig. 
  35.— 
  Cm'ocai'a 
  multilamellosa, 
  new 
  species. 
  A. 
  Transverse 
  section 
  of 
  specimen 
  D, 
  X 
  1G. 
  B. 
  Trans- 
  

   verse 
  section, 
  X 
  10. 
  C. 
  Section 
  through 
  a 
  branch, 
  X 
  16, 
  in 
  which 
  the 
  exterior 
  lamella 
  is 
  engendering 
  

   an 
  adventitious 
  branch. 
  D. 
  Longitudinal 
  section 
  (see 
  also 
  A), 
  X 
  16, 
  in 
  which 
  the 
  orifices 
  are 
  arranged 
  

   in 
  quincunx. 
  E. 
  Longitudinal 
  section, 
  X 
  16, 
  at 
  the 
  extremity 
  of 
  a 
  branch. 
  F. 
  Longitudinal 
  section, 
  

   X 
  16, 
  through 
  a 
  multilamellar 
  branch. 
  Lower 
  Cretaceous 
  (Valangian): 
  Sainte-Croix, 
  Switzerland 
  

  

  We 
  have 
  had 
  the 
  fortune 
  to 
  find 
  a 
  branch 
  containing 
  these 
  sup- 
  

   posed 
  lamellae 
  with 
  their 
  zone 
  of 
  growth. 
  The 
  longitudinal 
  section 
  

   of 
  this 
  branch 
  shows 
  that 
  the 
  tubes 
  are 
  arranged 
  in 
  a 
  different 
  direc- 
  

   tion 
  from 
  that 
  of 
  the 
  interior 
  lamella; 
  their 
  extremity 
  is 
  alone 
  visi- 
  

   ble 
  and 
  they 
  appear 
  there 
  shorter 
  than 
  they 
  are 
  in 
  reality. 
  The 
  

   study 
  of 
  the 
  transverse 
  section 
  confirms 
  this 
  arrangement. 
  

  

  