﻿II] 
  General 
  Geology 
  : 
  Lignitic 
  Eocene 
  65 
  

  

  Certain 
  sandy 
  and 
  cla3^ey 
  layers 
  containing 
  more 
  or 
  less 
  lig- 
  

   nitic 
  matter, 
  but 
  without 
  animal 
  fossil 
  remains, 
  lying 
  geograph- 
  

   ically 
  between 
  the 
  Midway 
  and 
  Lower 
  Claiborne 
  outcrops 
  in 
  

   Texas 
  and 
  Arkansas, 
  have 
  been 
  provisionally 
  referred 
  to 
  this 
  

   stage. 
  Lines 
  of 
  demarcation, 
  however, 
  between 
  this 
  and 
  higher 
  

   Eocene 
  stages, 
  have 
  been 
  difficult 
  to 
  locate 
  insomuch 
  as 
  materials 
  

   lithologically 
  similar 
  occur 
  in 
  this 
  and 
  many 
  of 
  the 
  higher 
  beds. 
  

  

  We 
  have 
  already 
  seen 
  how 
  in 
  Louisiana 
  these 
  beds 
  have 
  been 
  

   given 
  a 
  special 
  name, 
  "the 
  Mansfield 
  Group," 
  and 
  correlated 
  

   with 
  the 
  beds 
  at 
  the 
  base 
  of 
  the 
  Vicksburg 
  bluff", 
  then 
  with 
  the 
  

   Jackson 
  stage, 
  and 
  afterwards 
  with 
  some 
  pre- 
  Jackson 
  horizon. 
  

  

  Definite 
  proof 
  of 
  the 
  position 
  these 
  beds 
  occupy 
  was 
  first 
  given 
  

   in 
  Bulletins 
  of 
  American 
  Paleontology, 
  vol. 
  2, 
  p. 
  202, 
  1897. 
  

   The 
  locality 
  there 
  discussed, 
  — 
  Sabinetown, 
  Tex., 
  — 
  has 
  been 
  

   revisited 
  by 
  members 
  of 
  this 
  survey 
  and 
  now 
  cail 
  be 
  discussed 
  in 
  

   detail. 
  

  

  Areal 
  Distribution 
  

  

  The 
  Map. 
  — 
  The 
  area 
  represented 
  on 
  the 
  map 
  as 
  belonging 
  to 
  

   this 
  stage 
  may 
  have 
  its 
  boundaries 
  somewhat 
  modified 
  by 
  subse- 
  

   quent 
  investigation. 
  But 
  it 
  certainly 
  repsesents 
  the 
  truth 
  with 
  

   a 
  fair 
  degree 
  of 
  accuracy. 
  To 
  this 
  survey 
  belongs 
  the 
  credit 
  of 
  

   identifying 
  or 
  proving 
  the 
  existence 
  of 
  the 
  Lower 
  Lignitic, 
  in 
  

   this 
  State 
  by 
  means 
  of 
  fossil 
  remains, 
  and 
  being 
  able 
  to 
  say 
  pos- 
  

   itively 
  that 
  there 
  is 
  a 
  southern 
  peninsula-like 
  extension 
  of 
  this 
  

   stage 
  in 
  Louisiana 
  between 
  the 
  Red 
  and 
  Sabine 
  rivers. 
  

  

  Localities 
  

  

  Pendleton. 
  — 
  Along 
  the 
  Sabine 
  river 
  the 
  best 
  outcrops 
  are 
  seen 
  

   on 
  the 
  Texas 
  side. 
  Yet 
  since 
  they 
  throw 
  such 
  a 
  vast 
  amount 
  of 
  

   light 
  on 
  the 
  geology 
  of 
  Louisiana, 
  — 
  for 
  the 
  same 
  beds 
  must 
  

   occur 
  east 
  of 
  the 
  river 
  though 
  covered 
  by 
  detritus, 
  — 
  it 
  seems 
  

   highly 
  desirable 
  to 
  insert 
  them 
  here 
  in 
  detail 
  form. 
  

  

  The 
  following 
  section 
  may 
  be 
  seen 
  one-fourth 
  mile 
  above 
  the 
  

   ferry, 
  just 
  above 
  the 
  mouth 
  of 
  a 
  small 
  bayou. 
  

  

  9. 
  Light 
  gray 
  to 
  brownish 
  laminated 
  clay 
  7.5 
  ft. 
  

  

  8. 
  Ledge 
  of 
  impure 
  limestone 
  concretions 
  2.5 
  ft. 
  

  

  7. 
  Greenish 
  brown 
  and 
  light 
  blue 
  clayey 
  sand, 
  with 
  iron 
  

  

  concretions 
  and 
  fossils 
  4- 
  5 
  ft. 
  

  

  