﻿94 
  H. 
  S. 
  Williams 
  — 
  Recurrence 
  of 
  Devonian 
  

  

  3d. 
  On 
  the 
  other 
  hand, 
  it 
  is 
  pretty 
  evident 
  that 
  in 
  Labrador 
  

   and 
  Newfoundland 
  all 
  the 
  mountains 
  were 
  completely 
  covered 
  

   with 
  glacial 
  ice, 
  which 
  extended 
  far 
  out 
  over 
  the 
  bordering 
  

   continental 
  plateau. 
  But 
  this 
  was 
  at 
  that 
  time 
  probably 
  ele- 
  

   vated 
  above 
  the 
  sea-level, 
  so 
  that 
  it 
  is 
  doubtful 
  if 
  the 
  ice 
  ever 
  

   extended 
  far 
  into 
  the 
  sea. 
  The 
  facts 
  point 
  to 
  considerable 
  

   preglacial 
  elevations 
  of 
  land 
  followed 
  in 
  Labrador, 
  at 
  least, 
  by 
  

   a 
  period 
  of 
  extensive 
  depression 
  below 
  the 
  present 
  level, 
  and 
  

   subsequent 
  partial 
  elevation. 
  

  

  4th. 
  The 
  freshness 
  of 
  the 
  glacial 
  striae 
  in 
  exposed 
  places 
  and 
  

   the 
  small 
  amount 
  of 
  modification 
  which 
  has 
  taken 
  place 
  in 
  the 
  

   topography 
  since 
  the 
  retreat 
  of 
  the 
  ice 
  sustains 
  the 
  abundant 
  

   evidence 
  elsewhere 
  found 
  of 
  the 
  recent 
  date 
  of 
  the 
  glacial 
  

   period 
  ; 
  while 
  the 
  indications 
  of 
  recent 
  changes 
  of 
  level 
  point 
  

   to 
  terrestrial 
  rather 
  than 
  astronomical 
  causes 
  to 
  account 
  for 
  the 
  

   vicissitudes 
  of 
  the 
  glacial 
  period. 
  

  

  Art. 
  VIII. 
  — 
  On 
  the 
  Recurrence 
  of 
  Devonian 
  Fossils 
  in 
  

   strata 
  of 
  Carboniferous 
  Age 
  ; 
  by 
  Henry 
  S. 
  Williams. 
  

  

  [Read 
  before 
  the 
  Geological 
  Society 
  of 
  Ameiica 
  at 
  Baltimore, 
  December, 
  1894.] 
  

  

  The 
  fossils 
  which 
  form 
  the 
  subject 
  of 
  the 
  following 
  remarks 
  

   were 
  brought 
  to 
  my 
  notice 
  by 
  Dr. 
  J. 
  C. 
  Branner 
  during 
  the 
  

   progress 
  of 
  the 
  Geological 
  Survey 
  of 
  Arkansas. 
  They 
  were 
  

   collected 
  by 
  various 
  members 
  of 
  the 
  survey 
  from 
  a 
  dark 
  

   colored 
  limestone 
  and 
  associated 
  calcareous 
  shales 
  at 
  Spring 
  

   Creek, 
  a 
  few 
  miles 
  west 
  of 
  Batesville. 
  The 
  first 
  batch 
  of 
  fos- 
  

   sils 
  sent 
  me 
  were 
  in 
  a 
  rotten-stone, 
  originally 
  a 
  sandy 
  lime- 
  

   stone, 
  and 
  seemed 
  to 
  be 
  identical 
  with 
  the 
  Leiorhynchus 
  

   quadricostatum 
  of 
  the 
  Devonian 
  rocks 
  of 
  ]N"ew 
  York, 
  which 
  led 
  

   to 
  my 
  reporting 
  them 
  to 
  be 
  of 
  Devonian 
  age. 
  Afterwards 
  

   fossils 
  from 
  the 
  same 
  ledge 
  were 
  sent 
  which 
  were 
  reported 
  in 
  

   my 
  correspondence 
  to 
  be 
  of 
  undoubted 
  Carboniferous 
  age. 
  As 
  

   the 
  presence 
  of 
  Devonian 
  rocks 
  w 
  r 
  as 
  looked 
  for 
  but 
  had 
  not 
  

   been 
  definitely 
  proven 
  the 
  find 
  was 
  of 
  considerable 
  interest, 
  

   but 
  the 
  confusion 
  in 
  my 
  identifications 
  led 
  naturally 
  to 
  sus- 
  

   picion 
  of 
  either 
  mixing 
  of 
  the 
  evidence 
  or 
  error 
  in 
  the 
  identi- 
  

   fications. 
  

  

  McChesney* 
  had 
  previously 
  described 
  a 
  few 
  fossils 
  as 
  com- 
  

   ing 
  from 
  dark 
  shales 
  near 
  Batesville, 
  Ark., 
  and 
  probably 
  of 
  Ham- 
  

   ilton 
  (Devonian) 
  age 
  {Nucula 
  Vaseya?ia, 
  Nucula 
  f 
  rectangula 
  

   and 
  Pleurotomaria 
  nodomarginata). 
  And 
  the 
  black 
  shales 
  

   met 
  with 
  in 
  the 
  same 
  part 
  of 
  the 
  State 
  and 
  farther 
  west, 
  have 
  

  

  * 
  Descriptions 
  of 
  fossils, 
  Chicago 
  Acad. 
  Sci., 
  vol. 
  i, 
  pp. 
  37, 
  40 
  and 
  47. 
  

  

  