﻿HUDSON 
  RIVER 
  BEDS 
  NEAR 
  ALBANY 
  505 
  

  

  Walden, 
  on 
  the 
  banks 
  of 
  the 
  Wallkill, 
  11 
  miles 
  northwest 
  of 
  New- 
  

   burgh 
  on 
  the 
  Hudson, 
  two 
  localities 
  in 
  Orange 
  county 
  which 
  were 
  

   mentioned 
  by 
  Mather. 
  The 
  following 
  fossils 
  (according 
  to 
  Whit- 
  

   field's 
  identification) 
  were 
  collected 
  : 
  Orthis 
  pectinella, 
  

   O. 
  testudinaria, 
  O. 
  plica 
  tell 
  a, 
  Leptaena 
  seri- 
  

   cea, 
  Camarella 
  hemiplicata, 
  Strophomena 
  al- 
  

   ternata, 
  StreptorhynchuiS 
  planumbona 
  or 
  Str. 
  

   filitexta? 
  and 
  a 
  Tri 
  nucleus 
  concentricus. 
  Be- 
  

   sides 
  fragments 
  of 
  Chaetetes 
  or 
  F 
  a 
  vo 
  s 
  i 
  t 
  es, 
  a 
  crinoidal 
  

   column 
  and 
  a 
  fragment 
  of 
  C 
  o 
  n 
  u 
  1 
  a 
  r 
  i 
  a 
  (probably 
  trenton- 
  

   en 
  s 
  i 
  s). 
  

  

  The 
  greatest 
  interest 
  attaches 
  to 
  Orthispectinella, 
  

   and. 
  S 
  t 
  r 
  e 
  p 
  t 
  o 
  r 
  h 
  y 
  n 
  c 
  h 
  u 
  s 
  planumbona 
  or 
  filitexta, 
  

   as 
  these 
  forms 
  indicate 
  the 
  Trenton 
  age 
  of 
  that 
  shale. 
  

  

  I. 
  P. 
  Bishop 
  

  

  While 
  thus 
  the 
  fortunate 
  discoveries 
  of 
  fossils 
  other 
  than 
  grap- 
  

   tolites 
  in 
  the 
  " 
  Hudson 
  river 
  shales 
  " 
  began 
  to 
  furnish 
  evidence 
  

   of 
  the 
  Trenton 
  age 
  of 
  part 
  of 
  the 
  shales, 
  other 
  investigations, 
  

   notably 
  those 
  of 
  I. 
  P. 
  Bishop 
  (33) 
  tended 
  to 
  demonstrate 
  the 
  close 
  

   stratigraphic 
  relationship 
  of 
  the 
  Trenton 
  limestone 
  and 
  the 
  grap- 
  

   tolite-bearing 
  Hudson 
  river 
  shales; 
  for, 
  in 
  Columbia, 
  county, 
  it 
  

   was 
  established 
  by 
  Bishop 
  that 
  " 
  the 
  limestone 
  containing 
  Tren- 
  

   ton 
  fossils 
  immediately 
  underlies 
  the 
  graptolite 
  shales 
  of 
  the 
  Hud- 
  

   son 
  river 
  group 
  ". 
  

  

  Charles 
  Lapworth 
  , 
  

  

  An 
  entirely 
  new 
  course 
  to 
  the 
  (Solution 
  of 
  the 
  problem 
  of 
  the 
  

   age 
  of 
  the 
  Normans 
  kill 
  fauna 
  was 
  entered 
  on 
  by 
  Charles 
  Lap- 
  

   worth 
  (34), 
  who 
  studied 
  the 
  graptolite 
  faunas 
  from 
  numerous 
  

   localities 
  in 
  Canada,, 
  and 
  sought 
  to 
  determine 
  their 
  age 
  by 
  com- 
  

   paring 
  them 
  with 
  the 
  faunas 
  of 
  the 
  detailed 
  graptolite 
  zones 
  which 
  

   he 
  had 
  so 
  well 
  succeeded 
  in 
  establishing 
  in 
  Great 
  Britain. 
  A 
  

   farther 
  innovation 
  in 
  the 
  mode 
  of 
  viewing 
  the 
  problem 
  is 
  implied 
  

   in 
  Lapworth's 
  suggestion 
  that 
  the 
  Normans 
  kill 
  graptolite 
  beds 
  

   do 
  not 
  necessarily 
  represent 
  a 
  separate 
  stage 
  in 
  the 
  series 
  of 
  forma- 
  

   tions 
  but 
  are 
  probably 
  equivalent 
  with 
  certain 
  calcareous 
  strata 
  

  

  