﻿402 
  Forty-seventh 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  chert 
  in 
  courses 
  and 
  irregularly 
  disseminated. 
  Darker 
  colors 
  

   occur 
  locally, 
  notably 
  in 
  the 
  upper 
  beds 
  about 
  Peoria 
  (West 
  

   Berne), 
  which 
  are 
  very 
  dark 
  and 
  coarsely 
  crystalline. 
  The 
  chert 
  

   is 
  predominant 
  in 
  the 
  upper 
  beds 
  but 
  it 
  is 
  usually 
  present 
  also 
  in 
  

   the 
  lower 
  beds. 
  In 
  places 
  it 
  is 
  an 
  inconspicuous 
  feature 
  but 
  this 
  

   is 
  not 
  often 
  the 
  case. 
  

  

  Thin 
  partings 
  of 
  shale 
  occur 
  rarely. 
  About 
  Saugerties 
  the 
  

   lower 
  portion 
  of 
  the 
  limestone 
  is 
  impure 
  and 
  weathers 
  buff. 
  

   About 
  Clarksville 
  the 
  lower 
  members 
  are 
  very 
  pure, 
  free 
  from 
  

   chert 
  and 
  regularly 
  bedded. 
  

  

  Fossils 
  have 
  been 
  found 
  by 
  me 
  very 
  sparingly 
  south 
  of 
  Albany 
  

   county, 
  but 
  about 
  the 
  Helderbergs, 
  Schoharie 
  and 
  westward 
  the 
  

   lower 
  members 
  are 
  often 
  very 
  fossiliferous, 
  notably 
  from 
  Thomp- 
  

   son's 
  lake 
  to 
  Peoria 
  where 
  the 
  formation 
  comprises 
  many 
  fossil 
  

   coral 
  reefs, 
  some 
  of 
  large 
  size. 
  

  

  In 
  Greene 
  and 
  Ulster 
  counties 
  particularly, 
  the 
  outcropping 
  

   edge 
  of 
  the 
  formation 
  is 
  characterized 
  by 
  a 
  fringe 
  of 
  very 
  large 
  

   disconnected 
  blocks 
  occurring 
  at 
  various 
  intervals. 
  In 
  some 
  

   cases 
  these 
  blocks 
  lie 
  several 
  hundred 
  yards 
  from 
  the 
  main 
  out- 
  

   crop 
  of 
  the 
  formation 
  and 
  appear 
  to 
  be 
  glacial 
  erratics. 
  No 
  

   doubt 
  some 
  are, 
  but 
  I 
  have 
  found 
  that 
  many 
  are 
  undoubtedly 
  in 
  

   place, 
  having 
  resisted 
  the 
  erosion 
  which 
  has 
  removed 
  the 
  sur- 
  

   rounding 
  mass 
  of 
  limestone. 
  Notable 
  examples 
  of 
  these 
  blocks 
  

   may 
  be 
  seen 
  in 
  the 
  Kaaterskill 
  creek 
  region, 
  as 
  recorded 
  by 
  

   Davis, 
  on 
  the 
  road 
  from 
  Katshaan 
  southward, 
  on 
  the 
  road 
  north 
  

   from 
  Aquetuck 
  creek, 
  northeast 
  of 
  Coeymans 
  Hollow, 
  and 
  north 
  

   of 
  Cottekill. 
  

  

  Schoharie 
  grit. 
  — 
  This 
  is 
  a 
  local 
  deposit 
  which 
  is 
  characterized 
  

   in 
  the 
  vicinity 
  of 
  Schoharie, 
  and 
  extends 
  through 
  Schoharie 
  and 
  

   Albany 
  counties, 
  and 
  along 
  the 
  oastern 
  outcrop 
  to 
  Ulster 
  county. 
  

   It 
  is 
  a 
  very 
  arenaceous 
  limestone, 
  which 
  weathers 
  at 
  the 
  surface 
  

   to 
  a 
  dark 
  buff 
  or 
  brown, 
  porous, 
  massive, 
  rather 
  tough 
  sandrock. 
  

   It 
  merges 
  into 
  the 
  Onondaga 
  limestone 
  above, 
  but 
  is 
  more 
  

   sharply 
  separated 
  from 
  the 
  underlying 
  formation. 
  It 
  is 
  charac 
  

   terized 
  by 
  an 
  extensive 
  fauna, 
  of 
  which 
  the 
  members 
  appear 
  in 
  

   great 
  profusion 
  as 
  casts 
  in 
  the 
  weathered 
  sandrock. 
  East 
  from 
  

   Schoharie 
  the 
  formation 
  was 
  not 
  again 
  seen 
  until 
  reaching 
  the 
  

   eastern 
  face 
  of 
  the 
  Ilelderberg 
  mountains, 
  and 
  near 
  Clarksville, 
  

   where 
  it 
  is 
  well 
  exposed. 
  It 
  appears 
  to 
  be 
  absent 
  for 
  sor 
  i 
  miles 
  

  

  