﻿c) 
  Genus 
  

  

  Mso 
  Ri 
  sso 
  

   (Niso 
  , 
  

  

  1826, 
  (Niso, 
  one 
  of 
  

   the 
  fifty 
  Nereids, 
  

   writes 
  Risso, 
  Fern.) 
  

  

  117 
  ; 
  

  

  ITiso 
  he 
  n 
  dersoni 
  Bartsch 
  (named 
  for 
  John 
  j 
  

   Brooks 
  Henderson, 
  an 
  American 
  malacolo- 
  , 
  

   gist 
  and 
  Regent 
  of 
  the 
  Smithsonian 
  Ins- 
  ! 
  

   titution, 
  1870-1923.) 
  j 
  

  

  Mso 
  interru 
  pta 
  Sowerby 
  (inter 
  rupted; 
  j 
  

   with 
  continuity 
  Toroken; 
  each 
  whorl 
  is 
  i 
  

   defined 
  by 
  a 
  reddish-brown 
  line,) 
  ; 
  

  

  Niso 
  int 
  errupta 
  a 
  eglees 
  Bush 
  ( 
  Gr 
  , 
  gl 
  i 
  1 
  1 
  e 
  i|- 
  

   ing; 
  shell 
  semi-transparent, 
  smooth, 
  • 
  

   shining; 
  brown 
  more 
  or 
  less 
  suffused 
  i 
  

   with 
  purple; 
  brown 
  band; 
  no 
  white 
  bands,)! 
  

  

  ITiso 
  in 
  terru 
  pta 
  tricolor 
  P 
  all 
  (three- 
  ; 
  

  

  brown 
  with 
  brown 
  band 
  be- 
  : 
  ■ 
  

  

  colored; 
  pale 
  

  

  tween 
  two 
  v/hite 
  bands 
  at 
  

  

  Niso 
  m 
  ic 
  rof 
  oris 
  Dall 
  (v/ith 
  a 
  

   limbilicus 
  minute, 
  "This 
  has 
  

   umbilicus 
  than 
  any 
  other 
  figured 
  

   cies," 
  v/rites 
  Dall,) 
  

  

  IsTiso 
  splendidula 
  Sowe 
  r 
  by 
  (bright, 
  splen- 
  

   did; 
  this 
  is 
  a 
  magnificent 
  shell; 
  color 
  

   a. 
  handsome 
  yellow 
  brown 
  with 
  white 
  

  

  the 
  periphery,)! 
  

  

  small 
  door; 
  ^ 
  

  

  a 
  smaller 
  - 
  

  

  s-oe- 
  ' 
  

  

  I 
  

  

  I 
  

  

  a 
  ) 
  Genus 
  Stil 
  if 
  er 
  Br 
  o 
  - 
  

   derip 
  1852 
  , 
  T^a 
  s 
  c 
  7T 
  

  

  :_ 
  bands; 
  highly 
  polished,) 
  

  

  4. 
  F 
  amily 
  Stilif 
  eri 
  d 
  ae 
  , 
  (Lat. 
  stilus, 
  anything 
  long 
  and 
  pointed 
  like 
  ' 
  

   a 
  post, 
  a 
  style 
  -•- 
  fero, 
  to 
  carry. 
  Style-like 
  apex. 
  Apex 
  is 
  sharp} 
  

  

  Sti 
  li 
  fer 
  cu 
  rt 
  us 
  V 
  e 
  rri 
  ll 
  ( 
  shortened, 
  short 
  ;j 
  

   shell 
  broader 
  than 
  high; 
  with 
  a 
  very 
  i 
  

   low 
  spire.) 
  i 
  

  

  Stilifer 
  minimus 
  Dall 
  (very 
  small; 
  lengthl 
  

   3 
  ram. 
  ) 
  

  

  Stili 
  fer 
  m 
  in 
  utus 
  Dal 
  l 
  (minute; 
  smaller 
  

   than 
  minimus; 
  length 
  2 
  mm.) 
  \ 
  

  

  Sti 
  lif 
  er 
  stimpsoni 
  Verrill 
  ( 
  named 
  in 
  ho- 
  I 
  

   nor 
  of 
  ''/illi.am 
  Stirapson, 
  an 
  American 
  

   zoologist, 
  1832-1872.) 
  

  

  Stili 
  fer 
  verrilli 
  Da 
  ll 
  (named 
  for 
  Addisor 
  

   Emery 
  Verrill, 
  professor 
  of 
  Zoology 
  in 
  

   Yale 
  University, 
  1839-1927.) 
  

  

  Mucr 
  ona 
  l 
  ia 
  bulim 
  u 
  loides 
  Dal 
  l 
  (res 
  emb 
  ling 
  

   a 
  Bulimulus 
  or 
  Lymnaea; 
  "shell 
  much 
  the 
  j 
  

   shape 
  of 
  a 
  slender 
  Bulimulus 
  or 
  Lymnaea'' 
  

   writes 
  Dall. 
  ) 
  

  

  Mucronal 
  ia 
  m 
  a 
  mmillata 
  Da 
  ll 
  ( 
  rounded 
  like 
  i 
  

   a 
  nipple; 
  with 
  a 
  minute 
  subcylindrical 
  

   initial 
  whorl.) 
  : 
  

  

  Mucronalia 
  s 
  ua-"-a 
  Dal 
  l 
  (pleas 
  an 
  t, 
  deli 
  ght 
  -I 
  

   ful, 
  soft; 
  transition 
  from 
  mucro 
  to 
  I 
  

   v;horls 
  less 
  abrupt 
  than 
  in 
  M. 
  mammillata) 
  

  

  b 
  ) 
  G 
  enus 
  Mucronalia 
  A. 
  

   Adams 
  1860 
  . 
  (Lat.mu 
  - 
  

   cro, 
  raucronis, 
  a 
  

  

  sharp 
  point. 
  Fern. 
  

  

  ] 
  

  

  I 
  C. 
  ORDER 
  PTEROPODA 
  ! 
  

  

  ! 
  

  

  ! 
  (Gr. 
  pteron, 
  a 
  feather, 
  v/ing 
  -<- 
  pous, 
  podos, 
  foot. 
  So 
  named 
  because 
  

   t 
  the 
  anterior 
  lobes 
  of 
  the 
  foot 
  are 
  developed 
  in 
  the 
  form 
  of 
  winglike 
  

   j 
  organs. 
  7/ing-f 
  ooted. 
  ) 
  

   I 
  SUBORDER 
  THECGSG^IATA 
  

  

  (Gr, 
  theca, 
  a 
  case, 
  box 
  -(- 
  soma, 
  somat-, 
  iDody, 
  Species 
  having 
  a 
  shell,) 
  

  

  