﻿

  m:\\ 
  i'ORK 
  STATE 
  M 
  I 
  si;i 
  m 
  

  

  with 
  - 
  concentric 
  and 
  apparently 
  regular, 
  radiafcmg 
  corru- 
  

  

  "«>• 
  becoi 
  bsolete 
  toward 
  the 
  lateral 
  margins. 
  

  

  The 
  extreme 
  thinness 
  of 
  these 
  corrugated 
  shells 
  suggests 
  that 
  

   ,h, 
  '. 
  v 
  ; 
  '"' 
  much 
  macerated, 
  and 
  only 
  one 
  shell 
  layer 
  preserved. 
  

   Av 
  similar 
  corrugations 
  occur 
  in 
  exfoliated 
  and 
  torn] 
  

  

  "" 
  s 
  '*' 
  '•• 
  M 
  t>bol 
  ns 
  insignia, 
  where 
  the 
  chai 
  

  

  - 
  i 
  . 
  flne 
  radiating 
  striae 
  of 
  the 
  inner 
  layer 
  develop 
  under 
  like 
  

   conditions 
  into 
  a 
  system 
  of 
  wrinkles, 
  the 
  supposition 
  seems 
  legiti- 
  

   mate 
  thai 
  il 
  irrugations 
  are 
  only 
  the 
  result 
  of 
  maceration 
  

   and 
  com 
  F 
  ; 
  an 
  originally 
  more 
  convex 
  shell. 
  This 
  sup- 
  

   position 
  is 
  strengthened 
  by 
  the 
  occurrence 
  <>i 
  less 
  corrugated 
  

   shells, 
  furnishing 
  various 
  transitions 
  to 
  thicker, 
  smooth, 
  unex- 
  

   toliated 
  rah 
  The 
  latter, 
  instead 
  of 
  becoming 
  corrugated, 
  

   yielded 
  to 
  the 
  pressure 
  by 
  breaking 
  radially 
  in 
  two 
  or 
  more 
  seg- 
  

   iii- 
  fig, 
  12). 
  

  

  The 
  presence 
  of 
  a 
  strong 
  median 
  septum, 
  a 
  pedicle-groove, 
  

   traces 
  of 
  curving 
  laterals 
  and 
  a 
  posteriorly 
  Bituated 
  median 
  d 
  

   cular 
  scar 
  in 
  the 
  brachial 
  valve, 
  as 
  well 
  as 
  of 
  a 
  narrow 
  pedicle- 
  

  

  "' 
  N 
  '- 
  below 
  the 
  beak 
  of 
  the 
  pedicle-valve, 
  indicate 
  its 
  posil 
  

   in 
  the 
  genus 
  Le 
  p 
  i 
  o 
  b 
  o 
  1 
  o 
  

  

  ii 
  differs 
  from 
  all 
  other 
  species 
  of 
  Leptobolus 
  by 
  its 
  

   larger 
  sise. 
  SToung 
  valves 
  closely 
  resemble 
  specimens 
  of 
  Lep- 
  

   1 
  ° 
  b 
  ° 
  ' 
  » 
  B 
  insi 
  gni 
  s, 
  bu1 
  differ 
  in 
  being 
  less 
  convex, 
  having 
  

   a 
  less 
  prominent 
  beak, 
  a 
  thinner 
  shell 
  and 
  specially 
  a 
  more 
  regu- 
  

   lar 
  and 
  finer 
  concentric 
  striation. 
  

  

  Dimensions. 
  The 
  largest 
  specimen 
  observed 
  attains 
  a 
  width 
  

   °f 
  10.2 
  mm 
  and 
  a 
  length 
  (not 
  fully 
  preserved) 
  of 
  8 
  mm. 
  

  

  '■ 
  Trenton. 
  Normans 
  kill 
  shales. 
  Kenwood 
  and 
  Glen- 
  

   mont, 
  Dear 
  Albany, 
  Ml 
  Moreno, 
  Dear 
  Hudson. 
  

  

  - 
  h 
  ' 
  ■ 
  " 
  ' 
  M 
  - 
  ' 
  ;l 
  l 
  ,;1 
  pillifor 
  in 
  i 
  s 
  gp. 
  n. 
  (see 
  i»l 
  1 
  fie 
  

  

  A 
  ,,,iHl 
  v,] 
  > 
  rare 
  form 
  among 
  the 
  brachiopods 
  of 
  the 
  Normans 
  

   Ul 
  " 
  Bh 
  ales 
  bas 
  been 
  recognized 
  as 
  a 
  new 
  species 
  of 
  Schizo- 
  

  

  Pedicle 
  ralve 
  Bubcircular, 
  depressed 
  conical, 
  slop- 
  

   pqnally 
  in 
  all 
  directions, 
  beak 
  abruptly 
  projecting 
  just 
  benind 
  

  

  