﻿102 
  F. 
  W. 
  Sardeson 
  — 
  Lichenaria 
  typa 
  W. 
  i& 
  S. 
  

  

  returned 
  with 
  their 
  identification, 
  I 
  can 
  not 
  be 
  mistaken 
  as 
  to 
  

   the 
  species 
  which 
  thej 
  intended 
  to 
  describe. 
  Lichenaria 
  

   should 
  be 
  referred 
  to 
  the 
  Alcyonaria, 
  Tabulata, 
  near 
  Miche- 
  

   linia. 
  

  

  Lichenaria 
  typa 
  Winchell 
  and 
  Schuchert. 
  

  

  L. 
  ty^m 
  W. 
  and 
  S., 
  Final 
  rep. 
  Geol. 
  Sur. 
  Minn., 
  vol. 
  iii, 
  p. 
  83, 
  pi, 
  G. 
  figs. 
  10-13. 
  

   (1895). 
  L. 
  minor 
  Ulrich, 
  op. 
  cit., 
  p. 
  84, 
  fig. 
  5. 
  

  

  2. 
  3. 
  4. 
  

  

  ^, 
  

  

  Fig. 
  1. 
  Vertical 
  section 
  through 
  a 
  corallum, 
  showing 
  mural 
  pores 
  and 
  tabular. 
  

   The 
  latter 
  in 
  part 
  brokeu 
  away. 
  Fig. 
  2. 
  Transverse 
  section, 
  showing 
  mural 
  pores, 
  

   and 
  one 
  coenencbymal 
  coecum. 
  Fig. 
  3. 
  Diagram 
  of 
  the 
  surface 
  of 
  a 
  typical 
  speci- 
  

   men. 
  Fig. 
  4. 
  Ideal 
  vertical 
  section 
  of 
  specimen 
  growing 
  on 
  plane 
  surface. 
  

  

  Description. 
  CoraUum 
  hemispheric 
  or 
  irregular, 
  20™"^ 
  or 
  

   less 
  in 
  diameter, 
  composed 
  of 
  polygonal 
  cells 
  and 
  appearing 
  

   like 
  young 
  Favosites. 
  The 
  corallum 
  was 
  always 
  attached 
  to 
  a 
  

   shelloraMonticuliporoid 
  and 
  often 
  intergrown 
  with 
  the 
  latter. 
  

   The 
  cells 
  as 
  a 
  rule 
  rapidly 
  attain 
  the 
  size 
  of 
  1 
  to 
  2'"°' 
  diam- 
  

   eter. 
  The 
  -largest 
  cells 
  are 
  seen 
  on 
  largest 
  or 
  oldest 
  colonics 
  

   but 
  graduation 
  in 
  size 
  to 
  the 
  smallest 
  young 
  cells 
  normally 
  

   obtains 
  and 
  all 
  colonies 
  therefore 
  appear 
  immature. 
  The 
  cell, 
  

   walls 
  are 
  thin. 
  The 
  calycles 
  are 
  deeper 
  than 
  wide. 
  IS'ew 
  cells 
  

   develop 
  by 
  intermural 
  gemmation 
  at 
  the 
  angles 
  between 
  four 
  

   or 
  three 
  cells, 
  or 
  at 
  the 
  periphery 
  of 
  the 
  colony 
  intermediate 
  

   to 
  two 
  older 
  cells. 
  The 
  new 
  cell 
  is 
  at 
  first 
  a 
  round 
  vertical 
  

   (radial) 
  pore, 
  about 
  0*2™"^ 
  in 
  diameter, 
  then 
  as 
  it 
  enlarges 
  it 
  

   becomes 
  finally 
  polygonal 
  from 
  contact 
  (fig. 
  3). 
  When 
  the 
  

   growth 
  is 
  irregular 
  from 
  accidental 
  cause, 
  such 
  as 
  an 
  intergrow- 
  

   ing 
  Monticuliporoid, 
  some 
  of 
  the 
  cells 
  may 
  be 
  more 
  or 
  less 
  

   Auloporoid 
  in 
  their 
  development 
  but 
  there 
  is 
  no 
  Aulopora 
  

   stage 
  normally. 
  The 
  colony 
  evidently 
  arises 
  from 
  a 
  single 
  

   polyp 
  which 
  builds 
  a 
  recumbent 
  cell 
  and 
  which 
  early 
  buds 
  off 
  

   other 
  polyps, 
  resp. 
  cells. 
  

  

  The 
  cell 
  margins 
  are 
  not 
  notched, 
  as 
  now 
  seen, 
  except 
  by 
  the 
  

   incipient 
  mural 
  pores. 
  These 
  furrows 
  are 
  found 
  especially 
  at 
  

   the 
  angles 
  between 
  cells, 
  running 
  diagonally 
  between 
  two 
  or 
  

   branching 
  between 
  three 
  cells, 
  and 
  when 
  they 
  are 
  about 
  to 
  be 
  

   replaced 
  by 
  one 
  or 
  two 
  incipient 
  cells, 
  small 
  areas 
  result 
  such 
  

   as 
  Lindstrom 
  might 
  call 
  coenenchyma.'^ 
  The 
  corresponding 
  

   mural 
  pores 
  are 
  few 
  and 
  not 
  in 
  rows. 
  They 
  are 
  easily 
  found 
  

   in 
  transparent 
  sections 
  (fig. 
  1, 
  2\ 
  They 
  are 
  rather 
  large 
  and 
  

   penetrate 
  the 
  face 
  of 
  the 
  wall 
  less 
  often 
  than 
  the 
  corners. 
  

  

  * 
  Lindstrom, 
  op. 
  cit., 
  p. 
  10. 
  

  

  