﻿NIAGARA 
  FALLS 
  AND 
  VICINITY 
  229 
  

  

  progressively 
  increasing 
  in 
  length 
  backward, 
  the 
  anterior 
  pair 
  with 
  

   pincers 
  or 
  chelae; 
  second, 
  third 
  and 
  fourth 
  pair 
  six 
  to 
  seven-jointed, 
  

   and 
  covered 
  with 
  fine 
  spines; 
  fifth 
  pair 
  eight-jointed; 
  posterior 
  pair 
  

   consisting 
  of 
  eight 
  segments, 
  large 
  and 
  powerful, 
  with 
  a 
  large, 
  sub- 
  

   quadrate 
  basal 
  joint 
  in 
  each, 
  and 
  a 
  broad 
  terminal 
  " 
  paddle 
  ". 
  An- 
  

   terior 
  six 
  abdominal 
  segments 
  occupying 
  together 
  about 
  one 
  fourth 
  

   of 
  the 
  entire 
  body 
  length, 
  short, 
  broad 
  and 
  nearly 
  uniform 
  in 
  shape. 
  

   Succeeding 
  six 
  segments 
  are 
  ring-like, 
  progressively 
  decreasing 
  in 
  

   diameter, 
  thus 
  causing 
  a 
  tapering 
  of 
  the 
  body. 
  Telson 
  long 
  and 
  

   slender. 
  

  

  Eurypterus 
  lacustris 
  Harlan 
  (Hall. 
  1859. 
  Pal. 
  AL 
  Y. 
  3:407"^', 
  

   pi. 
  81, 
  81A, 
  81B, 
  83B) 
  

  

  Distinguishing 
  characters. 
  Animal 
  stout; 
  anterior 
  portion 
  of 
  the 
  

   abdomen 
  very 
  broad, 
  abruptly 
  tapering 
  beyond 
  the 
  sixth 
  segment; 
  

   penultimate 
  segment 
  quadrate, 
  without 
  lateral 
  flanges. 
  

  

  Very 
  abundant 
  in 
  the 
  Waterlime 
  of 
  North 
  Bufifalo. 
  

  

  Eurypterus 
  remipes 
  De 
  Kay 
  (Plate 
  18) 
  (Hall. 
  1859. 
  Pal. 
  

   N. 
  Y. 
  3:404^, 
  pi. 
  80, 
  80A, 
  83B) 
  

  

  Distinguishing 
  characters. 
  Animal 
  small, 
  with 
  lateral 
  body 
  mar- 
  

   gins 
  making 
  broad 
  outward 
  curves 
  and 
  tapering 
  very 
  gradually 
  

   backward. 
  Penultimate 
  segment 
  slightly 
  if 
  at 
  all 
  flanged. 
  

  

  Occasionally 
  in 
  the 
  Waterlime 
  of 
  North 
  Buffalo. 
  

  

  Eurypterus 
  pustulosus 
  Hall 
  (1859. 
  Pal. 
  N. 
  Y. 
  3:413*, 
  pi. 
  83B), 
  

   Eurypterus 
  giganteus 
  Pohlman 
  {Buffalo 
  soc. 
  nat. 
  sci. 
  Bui. 
  

   4:41) 
  

  

  Distinguishing 
  characters. 
  Cephalothorax 
  large, 
  short 
  and 
  very 
  

   broad; 
  eyes 
  on 
  the 
  median 
  transverse 
  line; 
  surface 
  strongly 
  pus- 
  

   tulose. 
  

  

  A 
  single 
  specimen 
  has 
  been 
  recorded 
  from 
  the 
  Waterlime 
  of 
  

   North 
  Buffalo. 
  

  

  Eurypterus 
  robustus 
  Hall, 
  Eurypterus 
  lacustis 
  var. 
  r 
  o 
  - 
  

   bust 
  us 
  Hall 
  (1859. 
  Pal. 
  N. 
  Y. 
  3:410*, 
  pi. 
  81C) 
  

  

  Distinguishing 
  characters. 
  Like 
  E. 
  lacustris, 
  but 
  larger 
  and 
  

   more 
  robust, 
  and 
  proportionately 
  narrower 
  over 
  the 
  anterior 
  ab- 
  

   dominal 
  region. 
  

  

  Common 
  in 
  the 
  Waterlime 
  at 
  North 
  Buffalo. 
  

  

  