﻿HUDSON 
  RIVER 
  BEDS 
  NEAR 
  ALBANY 
  585 
  

  

  EXPLANATIONS 
  OF 
  FIGURES 
  

   Plate 
  1 
  

  

  Pig. 
  

  

  1 
  A 
  pebble 
  of 
  Trenton 
  limestone 
  with 
  Pterygometopus 
  

  

  callicephalus, 
  A 
  m 
  p 
  y 
  x 
  hastatus 
  sp. 
  n. 
  and 
  

   Climacograptus 
  scharenbergi. 
  x2 
  

   Lower 
  Trenton 
  conglomerate, 
  Rysedorph 
  hill, 
  Rensselaer 
  co. 
  

   N. 
  Y. 
  

  

  Paterula 
  amii 
  Schuchert 
  

  

  2 
  A 
  partial 
  cast 
  of 
  a 
  pedicle-valve. 
  x6 
  

  

  Normans 
  kill 
  shale 
  of 
  Mt 
  Moreno 
  near 
  Hudson 
  N. 
  Y. 
  

  

  Schizotreta 
  papilliformis 
  sp. 
  n. 
  

  

  3 
  A 
  pedicle-valve. 
  x4 
  

  

  4 
  Profile 
  of 
  the 
  same. 
  x4 
  

  

  5 
  A 
  supposed 
  brachial 
  valve. 
  x6 
  

  

  Normans 
  kill 
  shale 
  of 
  Mt 
  Moreno 
  near 
  Hudson 
  N. 
  Y. 
  

  

  Leptobolus 
  walcotti 
  sp. 
  n. 
  

  

  '6 
  A 
  small 
  perfect 
  specimen; 
  showing 
  fine 
  concentric 
  striation. 
  

   Somewhat 
  compressed. 
  x6 
  

  

  7 
  An 
  internal 
  cast 
  of 
  a 
  brachial 
  valve; 
  showing 
  pedicle-groove, 
  

  

  median 
  septum 
  and 
  lateral 
  scars. 
  x4 
  

  

  8 
  The 
  interior 
  of 
  a 
  brachial 
  valve, 
  showing 
  median 
  septum 
  and 
  

  

  lateral 
  scars. 
  x6 
  

  

  9 
  A 
  very 
  young 
  specimen, 
  partially 
  exfoliated; 
  showing 
  radiat- 
  

  

  ing 
  striation 
  of 
  internal 
  surface 
  and 
  pedicle-groove. 
  xlO 
  

  

  10 
  A 
  strongly 
  concentrically 
  and 
  radially 
  corrugated 
  specimen; 
  

  

  the 
  usual 
  mode 
  of 
  preservation. 
  x4 
  

  

  11 
  The 
  interior 
  of 
  a 
  similar 
  specimen, 
  showing 
  pedicle-groove. 
  

  

  x4 
  

  

  12 
  A 
  shell, 
  which 
  instead 
  of 
  becoming 
  corrugated, 
  burst 
  on 
  com- 
  

  

  pression. 
  x4 
  

   Normans 
  kill 
  shale 
  of 
  Mt 
  Moreno 
  near 
  Hudson 
  N. 
  Y. 
  

  

  