﻿HUDSON 
  RIVER 
  BEDS 
  NEAR 
  ALBANY 
  493 
  

  

  James 
  Hall 
  

  

  Hall, 
  in 
  his 
  report 
  on 
  the 
  fourth 
  geological 
  district 
  (6), 
  also 
  

   accepted 
  the 
  term 
  Hudson 
  river 
  group, 
  but 
  remarked 
  that 
  along 
  

   the 
  Hudson 
  river, 
  where 
  disturbance 
  has 
  prevailed, 
  the 
  Utica 
  

   shale 
  and 
  Hudson 
  river 
  group 
  are 
  not 
  easily 
  separable 
  (6:30). 
  

   He, 
  hence, 
  assumed 
  the 
  presence 
  of 
  Utica 
  shale 
  in 
  the 
  Hudson 
  

   valley. 
  

  

  In 
  1847 
  the 
  same 
  author 
  furnished 
  the 
  means 
  of 
  separating 
  the 
  

   two 
  formations 
  by 
  describing 
  the 
  fossils 
  of 
  the 
  Hudson 
  river 
  

   group 
  (7). 
  The 
  fossils 
  described 
  under 
  the 
  caption 
  " 
  Hudson 
  

   river 
  group 
  " 
  are 
  components 
  of 
  two 
  entirely 
  different 
  faunas, 
  

   the 
  mollusk 
  fauna 
  of 
  the 
  Lorraine 
  beds 
  of 
  northwestern 
  New 
  

   York 
  and 
  the 
  graptolite 
  fauna 
  of 
  Normans 
  kill. 
  That 
  Hall 
  re- 
  

   tained 
  Mather's 
  and 
  Vanuxem's 
  views 
  of 
  the 
  homotaxy 
  of 
  the 
  

   Hudson 
  river 
  beds 
  with 
  the 
  Frankfort 
  beds 
  seems 
  to 
  the 
  writer 
  to 
  

   have 
  been 
  caused 
  principally 
  by 
  the 
  finding 
  of 
  Frankfort 
  slate 
  

   fossils 
  (Modiolopsis 
  nuculiformis, 
  Cleidopho- 
  

   rus 
  planulatus, 
  Lyrodesma 
  pulchella, 
  Mur- 
  

   chisonia 
  gracilis, 
  Carinaropsis 
  patelli- 
  

   formis, 
  C. 
  orbiculatus, 
  Belle 
  rophon 
  cancel- 
  

   1 
  a 
  t 
  u 
  s 
  ) 
  , 
  and 
  of 
  A 
  m 
  b 
  o 
  n 
  y 
  c 
  h 
  i 
  a 
  radiata, 
  which 
  is 
  

   characteristic 
  of 
  Vanuxem's 
  upper 
  division, 
  in 
  the 
  Hud- 
  

   son 
  river 
  shales 
  of 
  Waterford 
  {see 
  localities 
  of 
  these 
  

   fossils 
  in 
  v. 
  1, 
  Pal. 
  N. 
  T.) 
  These 
  fossils 
  seem, 
  indeed, 
  to 
  

   -connect 
  the 
  western 
  fauna 
  with 
  that 
  of 
  the 
  Normans 
  kill 
  beds, 
  

   but 
  it 
  may 
  be 
  remarked 
  here 
  that 
  the 
  writer 
  has 
  obtained 
  evi- 
  

   dence 
  showing 
  that 
  these 
  mollusks 
  nowhere 
  occur 
  in 
  the 
  same 
  

   beds 
  with 
  the 
  Normans 
  kill 
  graptolites, 
  but 
  in 
  actual 
  Lorraine 
  

   beds 
  which 
  are 
  stratigraphically 
  widely 
  separated 
  from 
  the 
  grap- 
  

   tolite 
  beds. 
  That 
  Hall 
  himself 
  did 
  not 
  feel 
  sure 
  of 
  his 
  correla- 
  

   tion 
  becomes 
  evident 
  from 
  an 
  interesting 
  footnote 
  on 
  page 
  329 
  

   of 
  the 
  above 
  cited 
  fundamental 
  work. 
  

  

  This 
  uncertainty 
  may 
  also 
  explain 
  why 
  in 
  the 
  third 
  volume 
  

   of 
  the 
  Paleontology 
  of 
  Neiv 
  Yorlc 
  (8: 
  14), 
  Hall 
  extended 
  the 
  term 
  

   Hudson 
  river 
  group 
  to 
  " 
  all 
  the 
  beds 
  from 
  the 
  Trenton 
  limestone 
  

   to 
  the 
  Shawangunk 
  conglomerate," 
  an 
  extension 
  of 
  the 
  term 
  

  

  