﻿NIAGARA 
  FALLS 
  AND 
  VICINITY 
  2^5 
  

  

  umbilicus 
  — 
  external 
  opening 
  of 
  the 
  hollow 
  axis 
  of 
  a 
  loose 
  coiled 
  shell 
  

   umbo 
  — 
  area 
  about 
  and 
  including 
  the 
  beak 
  in 
  pelecypods 
  and 
  brachiopods 
  

   unconformity 
  — 
  irregularity 
  in 
  the 
  succession 
  of 
  rock 
  beds 
  indicating 
  an 
  in- 
  

   tervening 
  period 
  of 
  erosion 
  

  

  valvular 
  — 
  pertaining 
  to 
  a 
  valve 
  

  

  varix 
  — 
  row 
  of 
  spines, 
  a 
  ridge 
  or 
  other 
  mark, 
  denoting 
  the 
  former 
  position 
  of 
  

  

  the 
  lip 
  on 
  the 
  shell 
  of 
  a 
  gastropod 
  (plural 
  varices) 
  

   vaulted 
  — 
  arched 
  

  

  ventral 
  — 
  pertaining 
  to 
  the 
  lower 
  side, 
  or 
  venter 
  

   ventricose 
  — 
  strongly 
  swollen, 
  or 
  bulging 
  

   vesicular 
  — 
  bearing 
  vesicles, 
  or 
  hollow 
  cavities 
  

   vestibular 
  area 
  — 
  area 
  surrounding 
  the 
  cell 
  apertures 
  of 
  some 
  bryozoa; 
  often 
  

  

  depressed 
  

   viscera 
  — 
  the 
  internal 
  organs 
  of 
  the 
  body 
  

  

  whorl 
  — 
  single 
  volution 
  of 
  a 
  coiled 
  shell 
  

  

  wing 
  — 
  posterior 
  larger 
  expansion 
  along 
  the 
  hinge-line 
  of 
  a 
  pelecypod 
  

  

  zoarlum 
  — 
  aggregates 
  of 
  the 
  polypites 
  of 
  a 
  bryozoan 
  colony 
  

  

  zooecium 
  — 
  the 
  bryozoan 
  cell 
  

  

  zooid 
  — 
  one 
  of 
  the 
  " 
  persons 
  " 
  or 
  individuals 
  of 
  a 
  zoarium 
  

  

  