﻿56 
  

  

  G. 
  E. 
  VINE 
  ON 
  THE 
  WEDLOCK 
  POITZOA. 
  

  

  It 
  is 
  only 
  after 
  very 
  careful 
  study 
  that 
  I 
  introduce 
  to 
  the 
  paleon- 
  

   tologist, 
  as 
  a 
  palaeozoic 
  type, 
  this 
  remarkable 
  genus. 
  Haime, 
  in 
  his 
  

   ' 
  Jurassic 
  Bryozoa,' 
  vindicates 
  his 
  use 
  of 
  the 
  word 
  JSpiropora 
  in 
  place 
  

   of 
  the 
  many 
  synonyms 
  which 
  have 
  been 
  introduced 
  into 
  scientific 
  

   literature 
  since 
  the 
  time 
  of 
  Lamouroux. 
  There 
  are 
  two 
  very 
  distinct 
  

  

  4, 
  5, 
  & 
  6. 
  

  

  -Spiropora 
  regularis, 
  Vine. 
  

   5 
  

  

  4. 
  Shows 
  the 
  general 
  habit 
  and 
  mode 
  of 
  branching, 
  and 
  character 
  of 
  unworn 
  

   cells: 
  X 
  12. 
  5. 
  Cells 
  worn, 
  showing 
  the 
  internal 
  cast 
  of 
  the 
  tubular 
  cell 
  : 
  

   X 
  24. 
  6. 
  Outline 
  cells 
  of 
  a 
  worn 
  specimen, 
  showing 
  arrangement 
  in 
  

   spirals: 
  X 
  24. 
  

  

  features 
  in 
  the 
  genus 
  ; 
  and 
  these, 
  as 
  defined 
  by 
  Jules 
  Haime, 
  may 
  be 
  

   briefly 
  noted: 
  — 
  1. 
  The 
  Zoarium 
  is 
  dendroid 
  . 
  with 
  forked 
  branches 
  ; 
  

   cells 
  elongated 
  and 
  closely 
  connected. 
  This 
  feature 
  is 
  apparent 
  in 
  

   the 
  Palaeozoic 
  type. 
  2. 
  " 
  The 
  peristomes 
  are 
  circular 
  and 
  more 
  or 
  

   less 
  projecting, 
  and 
  they 
  form 
  at 
  the 
  surface 
  of 
  the 
  branches 
  circles 
  

   which 
  usually 
  are 
  not 
  closed, 
  but 
  each 
  constitutes 
  one 
  of 
  the 
  turns 
  of 
  

   a 
  spire 
  so 
  many 
  times 
  interrupted. 
  These 
  rings 
  are 
  the 
  more 
  regular 
  

   the 
  more 
  distant 
  they 
  from 
  each 
  other. 
  "When 
  they 
  are 
  very 
  close 
  

   they 
  are 
  often 
  difficult 
  to 
  recognize 
  " 
  *. 
  This 
  feature 
  is 
  also 
  present 
  in 
  

   the 
  Palaeozoic 
  type. 
  Haime, 
  however, 
  speaks 
  of 
  his 
  species 
  as 
  being 
  

   perforated 
  " 
  with 
  very 
  small 
  and 
  round 
  pores." 
  This 
  feature 
  is 
  not 
  

   present 
  in 
  this 
  early 
  type; 
  indeed 
  perforated 
  pores 
  are 
  very 
  rare 
  in 
  

   Palaeozoic 
  Polyzoa. 
  I 
  have 
  seen 
  them 
  in 
  some 
  Carboniferous 
  species 
  

   of 
  Fenestella 
  f 
  ; 
  but 
  even 
  in 
  these 
  they 
  are 
  of 
  rare 
  occurrence 
  unless 
  

   specimens 
  are 
  specially 
  prepared 
  to 
  show 
  them. 
  In 
  his 
  Eocene 
  

   Bryozoa 
  Prof. 
  Eeuss 
  % 
  figures 
  and 
  describes 
  three 
  species 
  of 
  Spiro- 
  

   pora 
  : 
  — 
  S. 
  tenuissima, 
  Eeuss, 
  having 
  somewhat 
  the 
  general 
  character 
  

   of 
  Entalopliora 
  ; 
  S. 
  pulchella, 
  Eeuss 
  ; 
  and 
  S. 
  conferta, 
  Eeuss. 
  The 
  

   Silurian 
  species 
  more 
  closely 
  resembles 
  S. 
  pulchella 
  than 
  the 
  other 
  

   two 
  species 
  of 
  Eeuss, 
  both 
  in 
  the 
  character 
  and 
  in 
  the 
  ordinary 
  

   arrangement 
  of 
  the 
  cells. 
  It 
  must 
  not, 
  however, 
  be 
  taken 
  as 
  evidence, 
  

   satisfactorily 
  settled, 
  that 
  the 
  Palaeozoic 
  type 
  blends 
  naturally 
  with 
  

   the 
  Oolitic 
  and 
  Tertiary 
  types. 
  This 
  is 
  not 
  so. 
  The 
  evidence 
  is 
  

  

  * 
  Haime's 
  ' 
  Jurassic 
  Bryozoa,' 
  Genus 
  viii. 
  pp. 
  193, 
  194. 
  

   t 
  In 
  F. 
  plebeia, 
  M'Coy. 
  In 
  Alecto 
  frondosa, 
  James, 
  the 
  punctured 
  pores 
  are 
  

   a 
  marked 
  feature. 
  % 
  ' 
  Tertiary 
  Bryozoa 
  of 
  the 
  Alps.' 
  

  

  