﻿38 
  

  

  NOTE 
  ON 
  THE 
  OLIGOCENE 
  OF 
  TAMPA, 
  FLOKIDA, 
  THE 
  PANAMA 
  

   CANAL 
  ZONE, 
  AND 
  THE 
  ANTILLIAN 
  REGION. 
  

  

  By 
  William 
  H. 
  Ball, 
  Sc.T)., 
  LL.D. 
  

  

  Bead 
  10th 
  December, 
  1915. 
  

  

  The 
  line 
  dividing 
  the 
  Oligocene 
  from 
  tlie 
  Miocene 
  in 
  Europe 
  is 
  less 
  

   distinct 
  than 
  in 
  America, 
  and 
  the 
  particuhir 
  horizon 
  at 
  which 
  it 
  

   should 
  he 
  drawn 
  has 
  long 
  heen 
  a 
  subject 
  of 
  controversy 
  between 
  

   Continental 
  palaeontologists. 
  In 
  his 
  comparative 
  study 
  of 
  the 
  fossils 
  

   of 
  Martinique 
  and 
  Panama,' 
  M. 
  Cossmann, 
  in 
  referring 
  them 
  to 
  the 
  

   Miocene, 
  acknowledges 
  (p. 
  3) 
  that 
  this 
  conclusion 
  is 
  not 
  final, 
  and 
  that 
  

   it 
  is 
  possible 
  that 
  his 
  views 
  might 
  be 
  modified. 
  Nevertheless, 
  in 
  

   a 
  recent 
  criticism 
  of 
  ray 
  monograph 
  of 
  the 
  Tampa 
  fauna,- 
  in 
  the 
  

   Revue 
  Critique 
  de 
  PaUozoologie, 
  1915, 
  p. 
  119, 
  he 
  takes 
  me 
  severely 
  

   to 
  task 
  for 
  adopting 
  a 
  different 
  view. 
  In 
  general 
  it 
  is 
  of 
  very 
  

   slight 
  importance 
  by 
  what 
  name 
  we 
  call 
  a 
  fauna 
  provided 
  that 
  

   it 
  is 
  clear 
  how 
  we 
  define 
  it, 
  and 
  in 
  my 
  introduction 
  to 
  the 
  Miocene 
  

   volume 
  of 
  the 
  Maryland 
  Geological 
  Survey 
  I 
  have 
  shown 
  that 
  the 
  

   typical 
  Miocene 
  (Chesapeake) 
  of 
  Eastern 
  America 
  is 
  to 
  be 
  correlated 
  

   with 
  the 
  Miocene 
  of 
  North 
  Germany 
  and 
  Denmark, 
  and 
  not 
  with 
  the 
  

   warm-water 
  Miocene 
  of 
  South 
  Europe. 
  Our 
  warm-water 
  Miocene 
  of 
  

   Virginia 
  and 
  the 
  Carolinas 
  (Yorktown) 
  may 
  be 
  the 
  equivalent 
  of 
  the 
  

   latter, 
  but 
  it 
  is 
  absent 
  in 
  Florida, 
  wliere 
  a 
  faunal 
  abyss 
  separates 
  the 
  

   typical 
  Chesapeake 
  Miocene 
  from 
  the 
  uppermost 
  Oligocene 
  of 
  the 
  Alum 
  

   Eluff 
  and 
  Oak 
  Grove 
  horizon. 
  

  

  Oi'dinarily 
  I 
  do 
  not 
  consider 
  that 
  it 
  is 
  well 
  to 
  enter 
  into 
  controversy 
  

   upon 
  matters 
  of 
  opinion, 
  as 
  time 
  usually 
  settles 
  such 
  questions 
  to 
  the 
  

   general 
  satisfaction, 
  but 
  when 
  statements 
  of 
  fact 
  are 
  concerned 
  it 
  is 
  

   not 
  advisable 
  to 
  leave 
  errors 
  uncorrected 
  lest 
  the 
  reader 
  of 
  them 
  may 
  

   be 
  misled. 
  In 
  the 
  review 
  in 
  question 
  certain 
  statements 
  are 
  made 
  

   which 
  require 
  correction. 
  

  

  The 
  geological 
  Tertiary 
  column 
  in 
  the 
  Eloridian 
  region 
  is 
  very 
  

   complete, 
  and 
  ties 
  up 
  with 
  the 
  Panama 
  and 
  Antillian 
  Tertiary 
  

   absolutely, 
  so 
  far 
  as 
  the 
  correlation 
  between 
  the 
  horizon 
  represented 
  

   by 
  the 
  Orthaulax 
  pugnax 
  zone 
  of 
  Tam])a 
  is 
  concerned. 
  There 
  is 
  no 
  

   doubt 
  whatever 
  of 
  their 
  equivalence 
  in 
  fauna. 
  Both 
  M. 
  Cossmann 
  and 
  

   myself 
  agree 
  in 
  regarding 
  this 
  horizon 
  as 
  probably 
  equivalent 
  with 
  at 
  

   least 
  the 
  lower 
  part 
  of 
  the 
  Aquitanian 
  of 
  France. 
  Whether 
  this 
  be 
  

   called 
  Miocene 
  or 
  Oligocene 
  is 
  of 
  little 
  consequence, 
  provided 
  we 
  

   understand 
  clearly 
  how 
  these 
  terms 
  are 
  defined. 
  M. 
  Cossmann 
  considers 
  

   that 
  Megatylotus 
  is 
  characteristic 
  of 
  the 
  Oligocene, 
  and 
  states 
  that 
  it 
  is 
  

   absent 
  from 
  the 
  Tampa 
  fauna, 
  which 
  therefore 
  from 
  his 
  point 
  of 
  view 
  

   cannot 
  be 
  Oligocene. 
  Now 
  the 
  name 
  Meg 
  at 
  glottis 
  is 
  based 
  on 
  the 
  

   Natica 
  ormsatina 
  of 
  Deshayes, 
  which 
  is 
  an 
  Eocene 
  species 
  in 
  both 
  

   Europe 
  and 
  America, 
  but 
  reaches 
  up 
  to 
  the 
  lower 
  bed 
  at 
  Vicksburg, 
  

  

  1 
  Journ. 
  de 
  Conch., 
  vol. 
  Ixi, 
  1913, 
  pp. 
  1-64. 
  

   - 
  Bull. 
  U.S. 
  Nat. 
  Mus., 
  No. 
  90, 
  1915. 
  

  

  