﻿122 
  Twenty-eighth 
  Eeport 
  ox 
  the 
  State 
  Museum. 
  

  

  cms, 
  about 
  four 
  in 
  the 
  space 
  of 
  one 
  millimetre, 
  with 
  maculae 
  

   of 
  larger 
  cells, 
  the 
  centers 
  of 
  which 
  are 
  distant 
  from 
  each 
  

   other 
  about 
  four 
  millimetres; 
  the 
  larger 
  cells 
  two 
  or 
  three 
  

   times 
  the 
  size 
  of 
  the 
  smaller 
  ones. 
  

  

  In 
  its 
  mode 
  of 
  growth 
  this 
  form 
  resembles 
  Ch^etetes, 
  but 
  no 
  

   specimens 
  have 
  been 
  seen 
  where 
  the 
  depth 
  of 
  the 
  cells 
  is 
  more 
  

   than 
  two 
  millimetres. 
  The 
  cell-apertures 
  are 
  somewhat 
  more 
  

   regularly 
  hexagonal 
  than 
  in 
  the 
  preceding 
  forms, 
  and 
  by 
  

   this 
  character 
  it 
  is 
  readil}' 
  distinguishable 
  from 
  P. 
  confluens. 
  

   This 
  species 
  is 
  also 
  distinguished 
  from 
  the 
  latter 
  by 
  the 
  char- 
  

   acter 
  of 
  the 
  maculae 
  and 
  the 
  larger 
  cells. 
  In 
  P. 
  maculata 
  the 
  

   maculae 
  are 
  less 
  conspicuous, 
  and 
  the 
  larger 
  cells 
  do 
  not 
  

   differ 
  so 
  much 
  in 
  size 
  from 
  the 
  ordinary 
  ones. 
  

  

  STICTOPORA 
  Hall. 
  

  

  I 
  continue 
  the 
  use 
  of 
  the 
  generic 
  term 
  Stictopora 
  for 
  

   branching 
  forms 
  of 
  this 
  character, 
  where 
  the 
  cell-apertures 
  

   are 
  round 
  or 
  oval, 
  or 
  sometimes 
  partially 
  covered 
  by 
  a 
  project- 
  

   ing 
  lip 
  ; 
  and 
  where 
  the 
  intervening 
  space 
  may 
  be 
  plain 
  or 
  

   marked 
  by 
  slender 
  carinse, 
  strise 
  or 
  elevations 
  separating 
  the 
  

   rows 
  of 
  cells. 
  These 
  fossils 
  are 
  not 
  properhy 
  Ptilodyctia, 
  as 
  

   claimed 
  by 
  some 
  authors, 
  the 
  latter 
  being 
  simple 
  non-branch- 
  

   ing 
  stipes 
  with 
  cells 
  of 
  different 
  character 
  from 
  those 
  of 
  Stic- 
  

   topora. 
  

  

  Stictopora 
  semilis. 
  

  

  Plate 
  11, 
  Figs. 
  13-16. 
  

  

  Stictopora 
  similis 
  Hall. 
  Doc. 
  Edit. 
  28th 
  Rep. 
  St. 
  Mus. 
  Nat. 
  Hist. 
  Explanation 
  

  

  of 
  pi. 
  11. 
  figs. 
  13-16. 
  1876. 
  

   Compare 
  S. 
  punctipora 
  Hall, 
  Pal. 
  X. 
  Y., 
  vol. 
  ii, 
  p. 
  157, 
  pi. 
  40 
  B, 
  figs. 
  2a, 
  26, 
  2c. 
  1852. 
  

  

  Bryozoum 
  ramose, 
  branches 
  flattened, 
  width 
  from 
  two 
  to 
  

   three 
  millimetres 
  ; 
  margins 
  destitute 
  of 
  cells. 
  Cell-apertures 
  

   oval, 
  opening 
  directly 
  outward, 
  closely 
  arranged 
  in 
  oblique 
  

   rows 
  ; 
  length 
  .35 
  mm., 
  width 
  .18 
  to 
  .25 
  mm. 
  

  

  This 
  species 
  differs 
  from 
  S. 
  orbipora*, 
  occurring 
  in 
  the 
  

   same 
  locality, 
  by 
  its 
  thinner 
  branches 
  and 
  oval 
  cell-apertures. 
  

  

  * 
  Hall, 
  Trans. 
  Alb. 
  Inst., 
  vol. 
  x. 
  p. 
  61. 
  

  

  