﻿292 
  Geological 
  Survey 
  of 
  Louisiana 
  [Sect. 
  

  

  Cretaceous 
  

   Explanatory 
  Remarks 
  

  

  We 
  have 
  seen 
  how, 
  early 
  in 
  the 
  century, 
  several 
  fictitious 
  Cre- 
  

   taceous 
  localities 
  and 
  fossils 
  were 
  mentioned 
  from 
  eastern 
  Louis- 
  

   sana 
  and 
  how 
  Hilgard, 
  Hopkins, 
  Learch 
  and 
  others 
  have 
  since 
  

   mentioned 
  Exogyra 
  cosiata 
  and 
  Grypha^a 
  pitcheri 
  irotath.e 
  salt 
  licks 
  

   of 
  northern 
  Louisiana. 
  The 
  latter 
  fossil 
  having 
  been 
  proven 
  by 
  

   Vaughan 
  to 
  have 
  been 
  improperly 
  identified, 
  Exogyra 
  costata 
  has 
  

   remained 
  the 
  only 
  well 
  authenticated 
  Cretaceous 
  species 
  in 
  Louis- 
  

   iana, 
  It 
  is 
  owing 
  to 
  Mr. 
  Veatch's 
  energy 
  that 
  we 
  have 
  now 
  a 
  

   fairly 
  good 
  representation 
  of 
  the 
  Cretaceous 
  fauna 
  of 
  this 
  State. 
  

  

  Mr. 
  T. 
  W. 
  Stanton 
  of 
  the 
  U. 
  S. 
  Geological 
  Survey 
  has 
  kindly 
  

   looked 
  over 
  and 
  labeled 
  themajority 
  of 
  the 
  more 
  perfect 
  specimens; 
  

   and 
  hence 
  the 
  names 
  which 
  follow 
  may 
  be 
  regarded 
  as 
  his 
  iden- 
  

   tifications, 
  

  

  PELECYPODA 
  

   Exogyra 
  costata, 
  . 
  Plate 
  49, 
  fig. 
  i. 
  

  

  Syn. 
  — 
  E. 
  costata 
  Sb.y, 
  Jour. 
  Acad. 
  Nat. 
  Sci. 
  Phila., 
  vol. 
  2, 
  p. 
  43, 
  

   1820. 
  

   E. 
  costata 
  White, 
  U. 
  S. 
  G. 
  S., 
  4th 
  Ann. 
  Rept., 
  p. 
  304, 
  pis. 
  

  

  56-57. 
  figs. 
  I 
  and 
  2, 
  1884. 
  

   E. 
  costata 
  Whitfield, 
  U. 
  S. 
  G. 
  S.,Mon. 
  9, 
  p. 
  39, 
  pi. 
  6, 
  figs. 
  

  

  I 
  and 
  2, 
  1885. 
  

   E. 
  costata 
  Say, 
  Bull. 
  Am. 
  Pal., 
  vol. 
  i, 
  p. 
  291, 
  1896. 
  

   This 
  is 
  one 
  of 
  the 
  most 
  abundant 
  and 
  characteristic 
  moUuscan 
  

   species 
  in 
  the 
  Cretaceous 
  of 
  the 
  Atlantic 
  and 
  Gulf 
  States. 
  The 
  

   smaller 
  or 
  operculated 
  valve 
  only 
  is 
  herewith 
  figured 
  since 
  our 
  

   collections 
  have 
  not 
  as 
  yet 
  furnished 
  any 
  of 
  the 
  larger 
  valves. 
  

  

  Localities. 
  — 
  Ray 
  burn's 
  salt 
  work, 
  Bienville 
  parish, 
  La. 
  — 
  Veatch 
  

   (specimen 
  figured). 
  King's 
  salt 
  work. 
  — 
  Hilgard. 
  

   Gryphsea 
  vesicularis, 
  Plate 
  49, 
  fig. 
  2 
  ; 
  PI. 
  50, 
  figs, 
  i 
  and 
  2. 
  

  

  Syn. 
  — 
  O. 
  vesicularis 
  Lam., 
  Am. 
  du 
  Mus. 
  vol. 
  8, 
  p. 
  160, 
  pi. 
  22, 
  fig. 
  

   3, 
  1808. 
  

   GryphcBa 
  convexa 
  Morton, 
  Jour. 
  Acad. 
  Nat. 
  Sci. 
  Phila., 
  

   vol. 
  6, 
  pp. 
  79-80, 
  pi. 
  4, 
  figs. 
  I, 
  2, 
  1828-31. 
  

  

  