﻿12 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  name 
  Pamelia 
  formation 
  is 
  suggested 
  by 
  Professor 
  Cushing 
  for 
  this 
  

   series. 
  The 
  invasion 
  of 
  the 
  sea 
  during 
  this 
  stage 
  was 
  from 
  the 
  west, 
  

   and 
  this 
  district 
  marks 
  the 
  easternmost 
  edge 
  of 
  its 
  extent. 
  Here 
  

   alone 
  in 
  the 
  State 
  is 
  the 
  formation 
  well 
  exposed. 
  A 
  name 
  for 
  the 
  

   New 
  York 
  expression 
  of 
  the 
  series 
  seems 
  therefore 
  called 
  for. 
  It 
  

   overlapped 
  an 
  old 
  land 
  surface, 
  thins 
  rapidly 
  eastward 
  and 
  thickens 
  

   to 
  the 
  west, 
  and 
  its 
  presence 
  furnishes 
  for 
  the 
  first 
  time 
  an 
  adequate 
  

   explanation 
  of 
  the 
  great 
  thickness 
  of 
  limestone 
  reported 
  by 
  the 
  drill 
  

   in 
  the 
  deep 
  wells 
  of 
  northwestern 
  New 
  York. 
  

  

  On 
  reaching 
  the 
  base 
  of 
  the 
  Pamelia 
  formation 
  it 
  was 
  found 
  to 
  

   rest 
  everywhere 
  on 
  the 
  beds 
  which 
  had 
  been 
  referred 
  to 
  as 
  passage 
  

   beds 
  during 
  the 
  work 
  of 
  the 
  previous 
  season, 
  and 
  to 
  rest 
  on 
  them 
  

   with 
  the 
  most 
  prominent 
  unconformity 
  noted 
  among 
  the 
  sedimenta- 
  

   ries 
  in 
  northern 
  New 
  York. 
  The 
  basal 
  beds 
  of 
  the 
  Pamelia 
  forma- 
  

   tion 
  are 
  weak 
  and 
  therefore 
  seldom 
  exposed 
  but 
  when 
  seen 
  show 
  

   everywhere 
  a 
  thin 
  basal 
  conglomerate 
  and 
  sandstone. 
  The 
  under- 
  

   lying 
  formation 
  had 
  suffered 
  considerable 
  erosion 
  as 
  evinced 
  by 
  its 
  

   varying 
  thickness 
  and 
  the 
  varying 
  thickness 
  of 
  the 
  beds 
  of 
  the 
  

   Pamelia 
  formation 
  beneath 
  the 
  heavy 
  fossiliferous 
  limestone 
  bed, 
  

   as 
  shown 
  in 
  numerous 
  sections 
  in 
  small 
  areas. 
  The 
  time 
  interval 
  

   in 
  this 
  unconformity 
  seems 
  to 
  represent 
  the 
  whole, 
  or 
  the 
  major 
  

   part 
  of 
  Beekmantown 
  and 
  Chazy 
  time. 
  Nothing 
  that 
  can 
  be 
  corre- 
  

   lated 
  with 
  the 
  Beekmantown 
  formation 
  is 
  represented 
  in 
  the 
  section. 
  

  

  For 
  the 
  so 
  called 
  passage 
  beds 
  beneath, 
  the 
  name 
  Theresa 
  forma- 
  

   tion 
  is 
  proposed, 
  their 
  entire 
  thickness 
  being 
  well 
  exposed 
  in 
  the 
  

   township 
  of 
  that 
  name. 
  This 
  formation 
  seems 
  also 
  to 
  hold 
  a 
  fauna 
  

   not 
  before 
  noted" 
  in 
  the 
  State. 
  

  

  The 
  absence 
  of 
  the 
  Beekmantown 
  limestone, 
  the 
  great 
  unconform- 
  

   ity 
  between 
  the 
  Theresa 
  and 
  Pamelia 
  formations, 
  and 
  the 
  close 
  con- 
  

   nection 
  cf 
  the 
  former 
  with 
  the 
  Potsdam 
  into 
  which 
  it 
  grades, 
  and 
  

   of 
  the 
  latter 
  with 
  the 
  Lowville, 
  seems 
  to 
  add 
  weight 
  to 
  the 
  view 
  

   previously 
  urged, 
  that 
  the 
  Potsdam-Beekmantown 
  passage 
  beds 
  of 
  

   northern 
  New 
  York, 
  with 
  possibly 
  a 
  portion 
  of 
  the 
  Beekmantown, 
  

   are 
  so 
  closely 
  connected 
  with 
  the 
  Potsdam 
  that 
  they 
  must 
  of 
  neces- 
  

   sity 
  be 
  classed 
  with 
  them, 
  and 
  that, 
  since 
  the 
  normal 
  fauna 
  of 
  the 
  

   middle 
  and 
  upper 
  Beekmantown 
  is 
  plainly 
  a 
  Lower 
  Siluric 
  fauna, 
  

   the 
  line 
  of 
  division 
  between 
  the 
  two 
  great 
  rock 
  groups 
  is 
  to 
  be 
  found 
  

   somewhere 
  within 
  the 
  limits 
  of 
  what 
  has 
  heretofore 
  been 
  considered 
  

   as 
  Beekmantown. 
  In 
  this 
  connection 
  the 
  discovery 
  of 
  an 
  uncon- 
  

   formity 
  between 
  Brainerd 
  and 
  Seely's 
  group 
  A 
  and 
  group 
  B 
  of 
  the 
  

   Beekmantown, 
  made 
  by 
  Messrs 
  Ruedemann 
  and 
  Ulrich 
  in 
  the 
  Ticon- 
  

   deroga 
  region 
  the 
  past 
  summer, 
  comes 
  to 
  have 
  large 
  significance. 
  

  

  