﻿344 
  

  

  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  20 
  Onondaga 
  limestone 
  

  

  19 
  Oriskany 
  sandstone 
  

  

  18 
  Sandstone 
  of 
  Clarksville, 
  

   Helderberg 
  

  

  17 
  Limestone 
  of 
  Clarksville 
  

  

  16 
  Sandstone 
  

  

  15 
  Blue 
  limestone 
  

  

  14 
  Shaly 
  limestone, 
  

   Catskill 
  creek 
  

  

  13 
  2d 
  Pentamerus 
  limestone 
  

  

  12' 
  Water 
  limestone 
  

  

  A 
  try 
  pa 
  nasnta, 
  

   Delthyris, 
  two 
  species 
  (new), 
  

   Asaphas 
  selenurus. 
  

   Atrypa 
  elongata, 
  

   Delthyris 
  arenosa 
  ; 
  . 
  

   other 
  large 
  bivalves. 
  

   A 
  large 
  Orthoceras, 
  

   Pterinea 
  (bilobite), 
  

   Calymene 
  platys. 
  

   Pileopsis 
  tubifer. 
  

   Fucoides 
  canda-galli. 
  

   Delthyris 
  (new). 
  

   Trilobites 
  (two 
  new 
  genera), 
  

   Delthyris 
  macropleura, 
  

   Pileopsis 
  ? 
  (ventricose) 
  

   Atrypa 
  (two 
  species), 
  

   Strophomena 
  costellata. 
  

   Pentamerus 
  (Atrypa) 
  galeatus 
  

   Atrypa 
  lacunosa. 
  

   Tentaculites 
  annulatus, 
  

   Delthyris 
  (new), 
  Orthis 
  (new), 
  

   Various 
  univalves 
  unnamed 
  

   Cytherina, 
  a 
  large 
  species. 
  a 
  

  

  4 
  

  

  CD 
  

  

  u 
  

   a 
  

  

  7? 
  

  

  By 
  the 
  foregoing 
  quotation 
  it 
  will 
  be 
  seen 
  that 
  the 
  geological 
  

   formations 
  near 
  Clarksville 
  were 
  studied 
  at 
  least 
  as 
  early 
  as 
  1840. 
  

  

  It 
  is 
  rather 
  difficult 
  to 
  understand 
  to 
  which 
  formations 
  Mr 
  

   Conrad 
  ascribed 
  the 
  names 
  " 
  Limestones 
  and 
  sandstones 
  of 
  

   Clarksville," 
  or 
  how 
  he 
  came 
  to 
  repeat 
  his 
  formations 
  in 
  a 
  country 
  

   where 
  the 
  stratigraphy 
  is 
  so 
  clear. 
  The 
  fossil 
  Pentamerus 
  gale- 
  

   atus 
  establishes 
  no. 
  13 
  as 
  Lower 
  Pentamerus 
  and 
  Delthyris 
  macro- 
  

   pleura=Spirifer 
  macropleurus 
  determines 
  no. 
  14 
  as 
  Shaly 
  limestone. 
  

   That 
  the 
  " 
  Blue 
  limestone," 
  no. 
  15, 
  is 
  Bee-raft 
  or 
  Upper 
  Pentam- 
  

   erus 
  is 
  proven 
  by 
  the 
  following 
  quotation 
  from 
  Mr 
  Conrad 
  : 
  

   " 
  1) 
  a 
  blue 
  limestone 
  w 
  r 
  ell 
  marked 
  by 
  the 
  remains 
  of 
  a 
  large 
  spe- 
  

   cies 
  of 
  crinoidea 
  resembling 
  a 
  Scutella 
  in 
  form. 
  2) 
  Oriskany 
  

  

  oAmer. 
  jour. 
  sci. 
  April 
  1840. 
  38:89, 
  

  

  