﻿NIAGARA 
  FALLS 
  AND 
  VICINITY 
  l8l 
  

  

  Stropheodonta 
  corrugata 
  (Conrad) 
  (Fig. 
  85) 
  (Hall 
  1852. 
  

   Pal. 
  N. 
  Y. 
  2:59, 
  pi. 
  21) 
  

  

  Distinguishing 
  characters. 
  Semioval, 
  nearly 
  flat; 
  small, 
  acute 
  

   lateral 
  extensions 
  of 
  hinge; 
  fine, 
  prominent 
  striae 
  sometimes 
  bifur- 
  

  

  >^ 
  

  

  Fig, 
  85 
  Stropheodonta 
  corrugata; 
  with 
  surface 
  enlarged 
  

  

  eating 
  or 
  alternating 
  with 
  finer 
  ones; 
  oblique 
  folds 
  on 
  hinge 
  

   margin. 
  

  

  Found 
  in 
  the 
  Clinton 
  limestone 
  (?) 
  and 
  the 
  Clinton 
  lenses 
  at 
  Ni- 
  

   agara. 
  Rare. 
  

  

  Stropheodonta 
  profunda 
  Hall 
  (Fig. 
  86) 
  (1852. 
  Pal. 
  N. 
  Y. 
  

   2:61, 
  pi 
  21) 
  

  

  Distinguishing 
  characters. 
  Large, 
  semioval, 
  much 
  wider 
  than 
  

   high; 
  auriculate 
  hinge; 
  profoundly 
  concave 
  brachial 
  valve; 
  abruptly 
  

  

  Fig. 
  86 
  Stropheodonta 
  profunda 
  with 
  enlargement 
  of 
  striae 
  

  

  deflected 
  margins; 
  fine, 
  unequal 
  surface 
  striae; 
  papillose 
  or 
  punctate 
  

   interior. 
  

  

  Found 
  in 
  the 
  lower 
  and 
  upper 
  Clinton 
  limestone 
  at 
  Niagara. 
  Also 
  

   in 
  the 
  latter 
  bed 
  at 
  Lockport 
  (Hall). 
  

  

  I 
  

  

  