﻿42 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  the 
  extension 
  of 
  the 
  Hoyt 
  lies 
  to 
  the 
  east 
  and 
  south 
  of 
  Saratoga, 
  

   buried 
  from 
  sight 
  beneath 
  the 
  younger 
  rocks 
  which 
  cover 
  it 
  in 
  those 
  

   directions. 
  The 
  waters 
  were 
  clearer, 
  less 
  subject 
  to 
  incursions 
  of 
  

   sand, 
  Cryptozoon 
  reefs 
  flourished 
  as 
  they 
  did 
  not 
  in 
  the 
  normal 
  

   Theresa, 
  and 
  trilobites 
  and 
  gastropods 
  lived 
  on 
  the 
  surface 
  of 
  the 
  

   reefs, 
  where 
  we 
  find 
  their 
  fossil 
  remains 
  abundantly 
  today. 
  

  

  To 
  the 
  thickness 
  of 
  the 
  Hoyt 
  limestone 
  as 
  here 
  measured 
  there 
  

   needs 
  to 
  be 
  added 
  an 
  unknown 
  amount 
  which 
  we 
  estimate 
  as 
  prob- 
  

   ably 
  not 
  over 
  25 
  feet, 
  in 
  order 
  to 
  reach 
  the 
  summit 
  of 
  the 
  

   formation. 
  

  

  From 
  the 
  Hoyt 
  limestone 
  we 
  collected 
  the 
  following 
  fauna: 
  

   Cryptozoon 
  proliferum, 
  Lingulella 
  (Lingule- 
  

   pis) 
  acuminata, 
  Triblidium 
  cornutaforme, 
  

   Matherella 
  saratogensis, 
  (Murchisonia) 
  sp. 
  

   indet., 
  Matthewia 
  variabilis, 
  Pelagiella 
  hoyti, 
  

   P. 
  minutissima, 
  Agraulos 
  saratogensis, 
  Lon- 
  

   chocephalus 
  calciferus, 
  Dicellocephalus 
  

  

  hartti, 
  D. 
  tribulis. 
  

  

  LITTLE 
  FALLS 
  DOLOMITE 
  

  

  General 
  statement. 
  The 
  name 
  " 
  Calcif 
  erous 
  " 
  was 
  originally 
  

   applied 
  to 
  the 
  considerable 
  thickness 
  of 
  dolomitic 
  rocks 
  which 
  over- 
  

   lies 
  the 
  Potsdam 
  sandstone 
  in 
  the 
  Champlain 
  and 
  Mohawk 
  valleys. 
  

   Later 
  on 
  Clarke 
  and 
  Schuchert 
  replaced 
  this 
  by 
  the 
  name 
  Beekman- 
  

   town, 
  and 
  to 
  the 
  rather 
  unfossiliferous 
  phase 
  of 
  the 
  formation 
  in 
  

   the 
  Mohawk 
  valley 
  gave 
  the 
  local 
  name 
  of 
  Little 
  Falls 
  dolomite. 
  

   Brainard 
  and 
  Seely 
  were 
  the 
  first 
  carefully 
  to 
  measure 
  and 
  sub- 
  

   divide 
  the 
  formation 
  in 
  the 
  Champlain 
  valley, 
  making 
  five 
  subdi- 
  

   visions 
  which 
  they 
  lettered 
  from 
  A 
  to 
  E. 
  1 
  Recent 
  work 
  of 
  Ulrich, 
  

   Ruedemann 
  and 
  Cushing 
  showed 
  that 
  the 
  Little 
  Falls 
  dolomite 
  of 
  

   the 
  Mohawk 
  valley 
  was 
  the 
  equivalent 
  of 
  division 
  A 
  and 
  the 
  lower 
  

   part 
  of 
  division 
  B 
  of 
  the 
  Champlain 
  Beekmantown, 
  and 
  that 
  divi- 
  

   sions 
  C, 
  D 
  and 
  E 
  were 
  absent 
  along 
  the 
  Mohawk; 
  furthermore 
  

   that 
  an 
  unconformity 
  everywhere 
  separated 
  the 
  Little 
  Falls 
  from 
  

   the 
  overlying 
  Beekmantown, 
  and 
  that 
  the 
  natural 
  affiliations 
  of 
  the 
  

   former 
  were 
  with 
  the 
  Potsdam 
  and 
  Theresa 
  beneath, 
  rather 
  than 
  

   with 
  the 
  Beekmantown 
  above, 
  both 
  structurally 
  and 
  faunally. 
  2 
  In 
  

   the 
  Saratoga 
  region 
  the 
  Little 
  Falls 
  is 
  present 
  and 
  the 
  Beekman- 
  

   town 
  wholly 
  absent. 
  The 
  lowest 
  division 
  of 
  the 
  Beekmantown, 
  

  

  

  1 
  Am. 
  Mus. 
  Nat. 
  Hist. 
  Bui. 
  3, 
  p. 
  1. 
  

  

  2 
  N. 
  Y. 
  State 
  Mus. 
  Bui. 
  140, 
  p. 
  97-140. 
  

  

  