﻿NIAGARA 
  FALLS 
  AND 
  VICINITY 
  263 
  

  

  Glossary 
  

  

  aberrant 
  — 
  differing 
  from 
  the 
  type 
  

  

  acanthopores 
  — 
  hollow 
  spines 
  occurring 
  between 
  the 
  apertures, 
  on 
  the 
  frond 
  

  

  of 
  a 
  bryozoan 
  ' 
  

  

  acinus. 
  — 
  a 
  berry 
  

  

  adductor 
  muscles 
  — 
  closing 
  muscles 
  in 
  bivalve 
  shells 
  

   agglutinate 
  — 
  firmly 
  united 
  

   air-chambers 
  — 
  chambers 
  below 
  the 
  living 
  chamber 
  in 
  the 
  shells 
  of 
  

  

  cephalopods 
  

   alar 
  — 
  pertaining 
  to 
  "wings; 
  the 
  lateral 
  primary 
  septa 
  of 
  the 
  tetracoralla 
  

   alate 
  — 
  having 
  wing-like 
  expansions 
  

   ambulacral 
  areas 
  — 
  perforated 
  areas 
  in 
  the 
  test 
  of 
  an 
  echinoderm, 
  through 
  

  

  which 
  the 
  tubed 
  feet 
  project 
  

   anastomosing 
  — 
  uniting 
  to 
  form 
  a 
  net 
  work 
  

   angulated 
  — 
  with 
  angles 
  or 
  corners 
  

   ankylosed 
  — 
  firmly 
  united; 
  grown 
  together 
  

   annulations 
  — 
  rings, 
  or 
  ring-like 
  segments 
  

   annulus 
  — 
  a 
  ring; 
  a 
  segment 
  of 
  the 
  thorax 
  of 
  a 
  trilobite 
  

   antennae 
  — 
  paired 
  articulated 
  appendages 
  of 
  head 
  of 
  arthropod 
  — 
  trilobite 
  

   anterior 
  — 
  front 
  

  

  aperture 
  — 
  opening 
  of 
  shells, 
  cells, 
  etc. 
  

   apex 
  — 
  terminal 
  or 
  first-formed 
  portion 
  of 
  gastropod 
  shells 
  

   apophysis 
  — 
  a 
  calcareous 
  process 
  (in 
  interior 
  of 
  shells, 
  etc.) 
  

   appressed 
  — 
  pressed 
  closely 
  against 
  

   arcuate 
  — 
  arched; 
  bent 
  like 
  a 
  bow 
  

  

  articulated 
  — 
  joined 
  by 
  interlocking 
  processes, 
  or 
  by 
  teeth 
  and 
  sockets 
  

   asperate 
  — 
  rough 
  

  

  attenuated 
  — 
  tapering; 
  or 
  thinning 
  

  

  auricle 
  — 
  ear, 
  or 
  anterior 
  projection 
  of 
  the 
  hinge 
  of 
  many 
  pelecypods 
  

   auriculate 
  — 
  eared 
  

  

  aviculoid 
  — 
  resembling 
  Avicula, 
  winged 
  

   axial 
  canal 
  — 
  central 
  canal 
  of 
  crinoid 
  stem 
  

  

  axial 
  furrows 
  — 
  furrows 
  or 
  depressions 
  delimiting 
  the 
  axis 
  in 
  trilobites 
  

   axis 
  — 
  central 
  longitudinal 
  division 
  of 
  the 
  body 
  of 
  a 
  trilobite 
  

   azygous 
  — 
  unpaired; 
  the 
  azygous 
  side 
  of 
  the 
  calyx 
  of 
  a 
  crinoid 
  has 
  plates 
  

  

  differing 
  from 
  those 
  of 
  the 
  regular 
  sides 
  

  

  basals 
  — 
  lowest 
  cycle 
  or 
  cycles 
  (in 
  forms 
  with 
  dicyclic 
  base) 
  of 
  plates 
  in 
  tl^e 
  

  

  crinoidea 
  

   beak 
  — 
  area 
  of 
  the 
  apex 
  or 
  initial 
  point 
  of 
  a 
  shell 
  

   biconvex 
  — 
  both 
  valves 
  convex, 
  as 
  in 
  most 
  brachiopods 
  

   bifid 
  — 
  split 
  in 
  two 
  

   bifoliate 
  — 
  two-leaved 
  

   bifurcating 
  — 
  dividing 
  in 
  two, 
  forking 
  

  

  