﻿HUDSON 
  RIVER 
  BEDS 
  NEAR 
  ALBANY 
  535 
  

  

  Ctenobolbina 
  subrotunda 
  sp. 
  n. 
  

  

  Lepidoeoleus 
  janiesi, 
  Hall 
  & 
  Whitfield 
  sp. 
  

   In 
  the 
  more 
  argillaceous 
  rock 
  were 
  found: 
  

  

  Diplograptus 
  (Glyptograptus) 
  amplexicaulis 
  Hall 
  

  

  D. 
  foliaeeus, 
  Murchison 
  

  

  Proetus 
  of. 
  parviusculus, 
  Hall 
  

  

  The 
  combination 
  of 
  Diplograptus 
  amplexicaulis 
  

   with 
  S-chizocrinus 
  nodoeus 
  and 
  Proetus 
  cf 
  . 
  par- 
  

   viusculus 
  is 
  fairly 
  sufficient 
  evidence 
  of 
  the 
  Trenton 
  age 
  

   of 
  the 
  shales 
  and 
  sandstones 
  in 
  Fitzgerald's 
  quarry; 
  for 
  D. 
  

   amplexicaulis 
  occurs 
  typically 
  in 
  the 
  lower 
  and 
  middle 
  

   Trenton 
  and 
  Schizocrinus 
  nodosus 
  and 
  Proetus 
  

   parviusculus 
  (see 
  next 
  station) 
  are 
  known 
  from 
  the 
  Tren- 
  

   ton 
  only. 
  Ctenobolbina 
  subrotunda 
  is 
  nearest 
  re- 
  

   lated 
  to 
  the 
  Trenton 
  species 
  (Ct. 
  fulcrata 
  and 
  Ct. 
  crassa, 
  

   Ulrich) 
  of 
  that 
  genus 
  (see 
  description, 
  p. 
  576). 
  

  

  Station 
  24. 
  Brothers's 
  quarry, 
  south 
  Troy 
  

   The 
  outcrop 
  south 
  of 
  Troy 
  where 
  Whitfield 
  26 
  years 
  ago 
  col- 
  

   lected 
  the 
  Trenton 
  graptolite, 
  could 
  not 
  be 
  precisely 
  located; 
  at 
  

   least 
  no 
  information 
  of 
  the 
  former 
  occurrence 
  of 
  limestone 
  in 
  that 
  

   neighborhood 
  could 
  be 
  obtained. 
  There 
  were, 
  however, 
  several 
  

   localities 
  found 
  which 
  furnished 
  ample 
  evidence 
  of 
  the 
  presence 
  

   of 
  Trenton 
  fossils 
  and 
  which, 
  as 
  they 
  contain 
  calcareous 
  sand- 
  

   stone 
  banks 
  with 
  intercalated 
  impure 
  limestone 
  banks 
  and 
  shales, 
  

   may 
  be 
  identical 
  with 
  Mr 
  Whitfield's 
  collecting 
  ground. 
  

  

  The 
  most 
  important 
  locality 
  is 
  the 
  Brothers's 
  or 
  Laverys 
  quarry 
  

   station 
  24), 
  at 
  the 
  brow 
  of 
  the 
  hills 
  east 
  of 
  south 
  Troy. 
  Diplo- 
  

   graptus 
  amplexicaulis 
  is 
  found 
  here 
  in 
  great 
  numbers 
  

   in 
  black, 
  argillaceous 
  shale 
  at 
  the 
  east 
  side 
  of 
  the 
  quarry 
  and 
  

   more 
  sparingly 
  in 
  association 
  with 
  Corynoides 
  calicu- 
  

   1 
  a 
  r 
  i 
  s 
  in 
  similar 
  beds 
  at 
  the 
  opposite 
  side 
  of 
  the 
  quarry. 
  

  

  In 
  calcareous 
  sandstone 
  beds 
  which 
  contain 
  dark 
  impure 
  lime- 
  

   stone 
  banks 
  consisting 
  of 
  brachiopod 
  shells, 
  in 
  the 
  middle 
  part 
  

   of 
  the 
  quarry, 
  occur 
  brachiopods, 
  a 
  number 
  of 
  which 
  were 
  first 
  

   collected 
  by 
  Gilbert 
  Van 
  Ingen 
  of 
  Columbia 
  university 
  and 
  kindly 
  

   left 
  with 
  the 
  writer; 
  and 
  one 
  bed 
  is 
  filled 
  with 
  bryozoans. 
  The 
  

   beds 
  yielded: 
  

  

  