﻿394 
  R. 
  E. 
  Call 
  — 
  Silicified 
  Woods 
  of 
  Eastern 
  Arkansas. 
  

  

  Art. 
  XL. 
  — 
  The 
  Tertiary 
  Silicified 
  Woods 
  of 
  Eastern 
  

   Arkansas 
  ; 
  by 
  R. 
  Ellsworth 
  Call. 
  

  

  (Published 
  by 
  permission 
  of 
  the 
  State 
  Geologist 
  of 
  Arkansas.) 
  

  

  The 
  occurrence 
  of 
  silicified 
  wood 
  in 
  the 
  sands 
  and 
  gravels 
  

   of 
  the 
  Tertiary 
  of 
  the 
  Lower 
  Mississippi 
  Valley 
  has 
  long 
  been 
  

   known. 
  Aside, 
  however, 
  from 
  the 
  numerous 
  localities 
  men- 
  

   tioned 
  by 
  Hilgard,* 
  nearly 
  all 
  of 
  which 
  are 
  in 
  the 
  state 
  of 
  

   Mississippi, 
  little 
  attention 
  has 
  been 
  given 
  it. 
  Numerous 
  geolo- 
  

   gists 
  have 
  spoken 
  of 
  it 
  or 
  incidentally 
  studied 
  it 
  in 
  connection 
  

   with 
  other 
  investigations, 
  but 
  hitherto 
  no 
  attempt 
  has 
  been 
  

   made 
  to 
  recognize 
  the 
  species 
  and 
  fix 
  their 
  taxonomic 
  value, 
  

   if, 
  indeed, 
  they 
  possess 
  any 
  such 
  value. 
  Among 
  those 
  who 
  

   have 
  investigated 
  the 
  Orange 
  Sands 
  and 
  other 
  Tertiary 
  deposits 
  

   of 
  the 
  Mississippi 
  Valley 
  and 
  who 
  have 
  added 
  to 
  our 
  informa- 
  

   tion 
  as 
  to 
  the 
  occurrence 
  of 
  these 
  fossils 
  are 
  Hilgard,f 
  Pen- 
  

   rose,;}; 
  and 
  Knowlton.g 
  

  

  The 
  last 
  named 
  has 
  made 
  the 
  only 
  microscopic 
  study 
  of 
  

   these 
  fossils 
  which 
  is 
  on 
  record. 
  Since 
  his 
  investigations 
  are 
  

   based 
  upon 
  material 
  which, 
  for 
  the 
  most 
  part, 
  was 
  collected 
  by 
  

   the 
  writer, 
  it 
  is 
  thought 
  that 
  it 
  will 
  be 
  useful 
  to 
  place 
  on 
  

   record 
  in 
  this 
  form, 
  a 
  more 
  detailed 
  statement 
  of 
  the 
  conditions 
  

   of 
  the 
  occurrence 
  of 
  the 
  silicified 
  w^oods, 
  their 
  peculiarities, 
  

   their 
  structural 
  relations 
  and 
  their 
  stratigraphical 
  position, 
  in 
  

   the 
  hope 
  that 
  it 
  may 
  eventually 
  prove 
  to 
  be 
  of 
  use 
  in 
  correlat- 
  

   ing 
  the 
  deposits 
  in 
  which 
  they 
  are 
  found. 
  

  

  These 
  fossil 
  woods 
  occur 
  throughout 
  the 
  area 
  covered 
  by 
  

   Tertiary 
  sands 
  and 
  gravels 
  in 
  the 
  State 
  of 
  Arkansas. 
  When 
  

   in 
  large 
  masses 
  they 
  are 
  apparently 
  rarely 
  far 
  removed 
  from 
  

   beds 
  of 
  Tertiary 
  lignite 
  ; 
  if 
  in 
  small 
  masses 
  or 
  in 
  small 
  frag- 
  

   ments 
  they 
  occur 
  in 
  the 
  gravels 
  of 
  nearly 
  all 
  the 
  region 
  and 
  in 
  

   the 
  beds 
  of 
  the 
  streams 
  and 
  brooks 
  of 
  the 
  area 
  covered 
  by 
  the 
  

   Tertiary. 
  Occasionally 
  whole 
  trunks 
  of 
  trees 
  are 
  found, 
  often 
  

   partially 
  buried 
  in 
  the 
  sands 
  or 
  deeply 
  imbedded 
  in 
  the 
  

   gravels 
  which 
  cover 
  the 
  fiood 
  plains 
  of 
  the 
  creeks 
  and 
  ravines 
  

   within 
  the 
  Tertiary 
  area 
  and 
  especially 
  along 
  Crowley's 
  Ridge, 
  

   from 
  Helena 
  to 
  the 
  Missouri 
  line. 
  Specimens 
  have 
  been 
  

   obtained 
  from 
  logs 
  or 
  stumps 
  in 
  situ, 
  and 
  in 
  undisturbed 
  Ter- 
  

   tiary 
  beds 
  at 
  the 
  following 
  points: 
  Hope, 
  Hempstead 
  county; 
  

  

  ♦Agriculture 
  and 
  Geology 
  of 
  Mississippi, 
  1860, 
  pp. 
  20, 
  21, 
  et 
  seq. 
  

  

  f 
  Agriculture 
  and 
  Geology 
  of 
  Mississippi, 
  1860, 
  pp. 
  20, 
  21, 
  et 
  seq. 
  

  

  \ 
  First 
  Annual 
  Report 
  of 
  the 
  Geological 
  Survey 
  of 
  Texas, 
  1889; 
  " 
  A 
  Prelimi- 
  

   nary 
  Report 
  on 
  the 
  Geology 
  of 
  the 
  Gulf 
  Tertiary 
  of 
  Texas 
  from 
  Red 
  River 
  to 
  the 
  

   Rio 
  Grande." 
  By 
  R. 
  A. 
  F. 
  Penrose, 
  Jr., 
  pp. 
  1-101. 
  

  

  §See 
  Annual 
  Report 
  of 
  the 
  Arkansas 
  Geological 
  Survey 
  for 
  1889, 
  vol. 
  ii, 
  pp. 
  

   249-267, 
  Plates 
  IX-XI. 
  

  

  