﻿Tivenliofel 
  — 
  Wreford 
  and 
  Foraker 
  Limestones. 
  423 
  

  

  gents 
  of 
  the 
  globular 
  masses. 
  If 
  the 
  globules 
  developed 
  

   without 
  rolling, 
  the 
  shells 
  of 
  organisms 
  would 
  be 
  largely 
  

   those 
  of 
  pelagic 
  habitat, 
  and 
  it 
  would 
  seem 
  that 
  this 
  

   should 
  have 
  led 
  to 
  the 
  arrangement 
  of 
  the 
  long 
  axes 
  of 
  

   the 
  shells 
  parallel 
  to 
  the 
  upper 
  surfaces 
  of 
  the 
  "gel- 
  

   masses." 
  If 
  "gel-masses" 
  of 
  the 
  characteristics 
  postu- 
  

   lated 
  were 
  formed 
  and 
  rolled 
  about 
  by 
  wave 
  and 
  current, 
  

   it 
  would 
  appear 
  that 
  not 
  uncommonly 
  some, 
  and 
  quite 
  

   likely 
  many, 
  would 
  ultimately 
  have 
  reached 
  places 
  of 
  

   deposition 
  of 
  clastic 
  sediments. 
  This 
  would 
  occur 
  quite 
  

   commonly 
  in 
  such 
  a 
  series 
  of 
  sediments 
  as 
  compose 
  the 
  

   Pennsylvanian 
  and 
  Permian 
  strata 
  of 
  Kansas, 
  Oklahoma, 
  

   Missouri, 
  etc., 
  in 
  which 
  lateral 
  gradation 
  from 
  one 
  to 
  the 
  

   other 
  type 
  of 
  sediment 
  is 
  extremely 
  common 
  and 
  occurs 
  

   within 
  short 
  distances. 
  This, 
  apparently, 
  has 
  not 
  

   occurred. 
  

  

  If 
  the 
  circular 
  banding 
  of 
  cherts 
  developed 
  through 
  

   rolling 
  about, 
  with 
  banded 
  chert 
  nodules 
  of 
  large 
  size 
  

   there 
  should 
  be 
  an 
  abundance 
  of 
  evidence 
  of 
  wave 
  activity. 
  

   If 
  the 
  banding 
  developed 
  in 
  this 
  way, 
  the 
  bands 
  of 
  the 
  

   top 
  and 
  bottom 
  should 
  be 
  of 
  about 
  the 
  same 
  width 
  and 
  

   number 
  and 
  the 
  bands 
  of 
  the 
  horizontally 
  opposite 
  sides 
  

   should 
  also 
  be 
  of 
  about 
  the 
  same 
  width 
  and 
  number, 
  for 
  

   it 
  does 
  not 
  appear 
  reasonable 
  to 
  suppose 
  that 
  the 
  included 
  

   material 
  which 
  developed 
  the 
  banding 
  would 
  have 
  accu- 
  

   mulated 
  in 
  the 
  process 
  of 
  rolling 
  to 
  a 
  much 
  greater 
  extent 
  

   on 
  one 
  side 
  than 
  on 
  the 
  other, 
  while 
  the 
  silica 
  which 
  was 
  

   being 
  added 
  apparently 
  would 
  have 
  been 
  distributed 
  

   quite 
  uniformly 
  along 
  every 
  radius. 
  The 
  greater 
  width 
  

   of 
  the 
  bands 
  laterally, 
  as 
  compared 
  to 
  their 
  widths 
  in 
  the 
  

   vertical 
  direction, 
  might 
  have 
  developed 
  as 
  a 
  consequence 
  

   of 
  their 
  flattening 
  through 
  their 
  own 
  weight 
  or 
  the 
  weight 
  

   of 
  the 
  overlying 
  sediments, 
  because 
  of 
  silica 
  moving 
  from 
  

   the 
  top 
  to 
  the 
  sides. 
  

  

  The 
  evidence, 
  as 
  the 
  present 
  writer 
  sees 
  it, 
  does 
  not 
  

   favor 
  the 
  view 
  that 
  the 
  cherts 
  which 
  are 
  considered 
  in 
  

   this 
  article 
  were 
  formed 
  in 
  the 
  manner 
  which 
  has 
  just 
  

   been 
  outlined. 
  

  

  The 
  Fusulinas 
  of 
  the 
  Foraker 
  cherts 
  are 
  uniformly 
  dis- 
  

   tributed 
  and 
  show 
  no 
  concentration 
  in 
  any 
  way 
  whatever. 
  

   The 
  greater 
  number 
  of 
  modern 
  species 
  of 
  Foraminifera 
  11 
  

   are 
  bottom-dwellers 
  — 
  only 
  about 
  twenty-five 
  species 
  be- 
  

   ing 
  pelagic 
  — 
  and 
  the 
  chances 
  are 
  that 
  large 
  forms 
  like 
  

  

  11 
  Cushman, 
  J. 
  A., 
  Bull. 
  71, 
  IT. 
  S. 
  Nat. 
  Museum, 
  8, 
  1916. 
  

  

  Am. 
  Jour. 
  Sci.— 
  Fourth 
  Sertes, 
  Vol. 
  XLVIT, 
  No. 
  282.— 
  June, 
  1919. 
  

   29 
  

  

  