﻿GEOLOGY 
  OF 
  SARATOGA 
  SPRINGS 
  AND 
  VICINITY 
  39 
  

  

  while 
  the 
  Little 
  Falls 
  dolomite 
  at 
  Saratoga 
  has 
  about 
  the 
  same 
  thick- 
  

   ness 
  as 
  it 
  has 
  to 
  the 
  west 
  and 
  north. 
  Miller 
  has 
  already 
  made 
  a 
  

   similar 
  suggestion. 
  1 
  

  

  The 
  Hoyt 
  limestone 
  is 
  composed 
  of 
  alternating 
  beds 
  of 
  dolomite 
  

   and 
  of 
  limestone, 
  and 
  is 
  comparatively 
  thick 
  bedded. 
  The 
  color 
  

   is 
  usually 
  dark 
  and 
  often 
  black. 
  Several 
  beds 
  of 
  black 
  oolite 
  occur, 
  

   chiefly 
  in 
  the 
  lower 
  portion 
  of 
  the 
  formation. 
  Many 
  of 
  the 
  lime- 
  

   stone 
  beds 
  furnish 
  abundant 
  fossils, 
  chiefly 
  trilobites 
  in 
  very 
  frag- 
  

   mentary 
  condition. 
  Along 
  with 
  these 
  are 
  small 
  gastropods, 
  which 
  

   are 
  much 
  less 
  abundant. 
  Lingulella 
  acuminata 
  occurs 
  

   everywhere. 
  Perhaps 
  the 
  most 
  striking 
  fossils 
  of 
  the 
  formation 
  are 
  

   the 
  big, 
  reeflike 
  masses 
  of 
  the 
  organism 
  of 
  unknown 
  nature, 
  known 
  

   as 
  Cryptozoon. 
  The 
  genus 
  was 
  originally 
  described 
  by 
  Hall 
  from 
  the 
  

   exposures 
  by 
  the 
  roadside 
  just 
  north 
  of 
  the 
  Hoyt 
  quarry 
  (plates 
  

   3 
  and 
  4), 
  where 
  a 
  bared 
  and 
  glaciated 
  surface 
  of 
  the 
  rock 
  is 
  

   splendidly 
  exposed 
  over 
  a 
  considerable 
  area. 
  Reefs 
  and 
  masses 
  

   of 
  more 
  than 
  one 
  species 
  of 
  this 
  genus 
  are 
  of 
  common 
  occurrence 
  

   in 
  both 
  the 
  Hoyt 
  limestone 
  and 
  the 
  overlying 
  Little 
  Falls 
  dolomite, 
  

   in 
  the 
  latter 
  ranging 
  throughout 
  the 
  Mohawk 
  and 
  Champlain 
  val- 
  

   leys. 
  The 
  reeflike 
  nature 
  of 
  the 
  masses 
  is 
  well 
  shown 
  in 
  many 
  

   places 
  in 
  the 
  district, 
  notably 
  so 
  perhaps 
  in 
  the 
  railroad 
  cut 
  just 
  

   east 
  of 
  Greenfield 
  depot. 
  Midway 
  of 
  this 
  cut 
  is 
  shown 
  a 
  Crypto- 
  

   zoon 
  reef 
  of 
  massive 
  limestone 
  (6 
  feet 
  thick). 
  Toward 
  the 
  west 
  

   this 
  bed 
  breaks 
  up 
  into 
  thinner 
  bedded 
  material 
  which 
  at 
  the 
  same 
  

   time 
  becomes 
  very 
  sandy 
  and 
  with 
  layers 
  of 
  nearly 
  pure 
  quartz 
  

   sand, 
  while 
  to 
  the 
  east 
  it 
  remains 
  pure 
  limestone, 
  though 
  the 
  Cryp- 
  

   tozoon 
  gives 
  out. 
  The 
  east 
  is 
  taken 
  to 
  be 
  the 
  seaward 
  and 
  the 
  

   west 
  the 
  landward 
  side 
  of 
  the 
  old 
  reef. 
  • 
  

  

  The 
  Hoyt 
  limestone 
  is 
  well 
  shown 
  in 
  the 
  so-called 
  railroad 
  

   quarry, 
  i 
  mile 
  north 
  of 
  Saratoga 
  (plates 
  5 
  and 
  6). 
  But 
  neither 
  

   base 
  nor 
  summit 
  shows 
  there 
  and 
  the 
  outcrop 
  is 
  an 
  isolated 
  one 
  

   lying 
  between 
  two 
  branches 
  of 
  a 
  fault, 
  so 
  that 
  it 
  tells 
  nothing 
  what- 
  

   ever 
  in 
  regard 
  to 
  the 
  stratigraphic 
  relations 
  of 
  the 
  formation. 
  It 
  

   has 
  a 
  local 
  high 
  dip 
  to 
  the 
  southwest 
  due 
  to 
  proximity 
  to 
  a 
  fault, 
  

   shows 
  a 
  thickness 
  of 
  some 
  20 
  feet 
  of 
  the 
  formation 
  including 
  a 
  

   • 
  splendid 
  Cryptozoon 
  reef, 
  and 
  is 
  an 
  excellent 
  locality 
  for 
  fossils. 
  

   But 
  for 
  the 
  stratigraphy 
  we 
  must 
  go 
  to 
  the 
  exposures 
  in 
  the 
  railroad 
  

   cuts 
  and 
  the 
  vicinity 
  of 
  the 
  Hoyt 
  quarry. 
  Here 
  an 
  excellent 
  section 
  

   of 
  the 
  greater 
  part 
  of 
  the 
  formation 
  is 
  obtained, 
  overlying 
  the 
  

   Theresa 
  formation, 
  hence 
  making 
  certain 
  its 
  stratigraphic 
  position. 
  

   The 
  summit, 
  however, 
  is 
  not 
  seen, 
  though 
  if 
  we 
  are 
  correct 
  in 
  

  

  1 
  N. 
  Y. 
  State 
  Mus. 
  Bui. 
  153, 
  P- 
  3°- 
  

  

  