﻿NIAGARA 
  FALLS 
  AND 
  ViCiNlTY 
  213 
  

  

  Pleurotomaria 
  pervetusta 
  (Conrad) 
  (Fig. 
  143) 
  (1852. 
  Pal 
  

   N. 
  F. 
  2:12, 
  pi. 
  4 
  (bis)) 
  

  

  Distinguishing 
  characters. 
  Small 
  size; 
  depressed 
  conic 
  spire, 
  the 
  

   volutions 
  strongly 
  embracing; 
  whorls 
  

   about 
  four, 
  gradually 
  enlarging; 
  large 
  um- 
  

   bilicus 
  extending 
  to 
  the 
  apex. 
  

  

  Found 
  in 
  the 
  upper 
  Medina 
  sandstones 
  

   of 
  the 
  Niagara 
  sections. 
  Also 
  at 
  Lockport 
  

   (Hall). 
  

  

  Genus 
  bucania 
  Hall 
  

   [Ety. 
  : 
  bucina, 
  a 
  trumpet] 
  

   (1847. 
  Pal' 
  A', 
  y- 
  I 
  -32) 
  

  

  Shells 
  coiled, 
  a 
  single 
  plane, 
  with 
  the 
  

   spire 
  equally 
  concave 
  on 
  either 
  side 
  and 
  

  

  11 
  ^1 
  1 
  . 
  -Ml 
  1 
  , 
  Fig. 
  143 
  Pleurotomaria 
  pervetusta 
  

  

  all 
  the 
  volutions 
  visible; 
  outer 
  whorl 
  ven- 
  

  

  tricose; 
  all 
  whorls 
  embracing 
  to 
  some 
  extent, 
  having 
  an 
  inner 
  con- 
  

   cavity; 
  aperture 
  rounded, 
  oval, 
  somewhat 
  compressed 
  on 
  the 
  inner 
  

   side 
  from 
  contact 
  with 
  preceding 
  whorl. 
  

  

  Bucania 
  trilobata 
  (Conrad) 
  (Fig. 
  144) 
  (Hall. 
  1852. 
  

   Pal. 
  N. 
  Y. 
  2:13, 
  Pl- 
  4 
  (bis)) 
  

  

  Distinguishing 
  characters. 
  Suborbicular 
  form; 
  three- 
  

   Pig. 
  144 
  Bucania 
  lobcd 
  volutious, 
  all 
  of 
  which 
  are 
  visible 
  ; 
  last 
  whorl 
  

  

  trilobata 
  

  

  greatly 
  expanded; 
  aperture 
  wider 
  than 
  long. 
  

   Found 
  at 
  Medina 
  and 
  Lockport 
  and 
  fragments 
  in 
  the 
  upper 
  

   Medina 
  of 
  Niagara 
  indicate 
  its 
  presence 
  there. 
  

  

  Class 
  CONULARIDA 
  

  

  Paleozoic 
  mollusks 
  of 
  doubtful 
  systematic 
  position, 
  resembhng 
  

   some 
  modern 
  Pteropoda, 
  but 
  only 
  distantly 
  and 
  ancestrally 
  related 
  

   to 
  them. 
  Shells 
  conic 
  or 
  tubular, 
  elongate, 
  septate 
  and 
  variously 
  

   ornamented. 
  

  

  Genus 
  conularia 
  Miller 
  

  

  [Ety.: 
  diminutive 
  of 
  conus, 
  a 
  cone] 
  

  

  (182 
  1. 
  Sowerby. 
  Mineral 
  conchology, 
  3:107) 
  

  

  Shell 
  elongated, 
  pyramidal, 
  with 
  the 
  transverse 
  section 
  varying 
  

   from 
  quadrangular 
  to 
  octagonal; 
  angles 
  indented 
  by 
  longitudinal 
  

   grooves. 
  The 
  surface 
  is 
  variously 
  ornamented 
  by 
  transverse 
  or 
  

  

  Q 
  

  

  