﻿394 
  Panama 
  Shells. 
  littorinid^. 
  

  

  vex, 
  with 
  a 
  well 
  impressed 
  suture 
  ; 
  last 
  whorl 
  angular 
  at 
  the 
  

   periphery 
  : 
  aperture 
  subovate 
  : 
  labrum 
  thin 
  : 
  columella 
  straight 
  : 
  

   umbilicus 
  wanting. 
  

  

  Mean 
  divergence 
  about 
  23° 
  ; 
  length 
  .185 
  inch 
  ; 
  breadth 
  .055 
  

   inch 
  ; 
  length 
  of 
  spire 
  .14 
  inch. 
  

  

  Station. 
  — 
  Unknown. 
  

  

  Habitat. 
  — 
  Panama 
  ; 
  C. 
  B. 
  A. 
  ! 
  

  

  3 
  specimens 
  were 
  found 
  in 
  the 
  sand. 
  

  

  231. 
  liittorina 
  (I) 
  angiostoma. 
  Nov. 
  sp. 
  

  

  Shell 
  obliquely 
  ellipsoidal 
  : 
  dingy 
  white 
  : 
  surface 
  covered 
  

   with 
  deep 
  regular 
  spiral 
  striae 
  : 
  apex 
  obtuse 
  : 
  spire 
  rather 
  small 
  

   with 
  curvilinear 
  outlines 
  : 
  whorls 
  three 
  and 
  one 
  half, 
  very 
  con- 
  

   vex, 
  with 
  a 
  distinct 
  suture 
  : 
  aperture 
  subefiuse, 
  nearly 
  semi-ellip- 
  

   tical, 
  the 
  inner 
  lip 
  being 
  straight, 
  and 
  well 
  developed 
  : 
  umbilicus 
  

   conspicuous. 
  

  

  Mean 
  divergence 
  about 
  85° 
  ; 
  length 
  .13 
  inch 
  ; 
  breadth 
  .1 
  

   inch 
  ; 
  length 
  of 
  spire 
  .055 
  inch. 
  

  

  The 
  generic 
  character 
  of 
  this 
  species 
  is 
  doubtful. 
  The 
  shell 
  

   resembles 
  some 
  small 
  species 
  of 
  Narica. 
  

  

  Station. 
  — 
  Unknown. 
  

  

  Habitat. 
  — 
  Panama 
  ; 
  C. 
  B. 
  A. 
  ! 
  

  

  3 
  specimens 
  were 
  found 
  in 
  the 
  sand. 
  

  

  232. 
  liittorina 
  aispera. 
  

  

  Synonymy. 
  

  

  Littorina 
  aspera 
  Phil, 
  in 
  Proc. 
  Zool. 
  Soc. 
  Lond. 
  p. 
  139. 
  Dec. 
  1845. 
  

   Phil. 
  Abbild. 
  II. 
  pi. 
  4. 
  f. 
  13. 
  Mar. 
  1847. 
  

  

  The 
  young 
  are 
  very 
  commonly 
  much 
  angulated 
  near 
  the 
  

   periphery 
  of 
  the 
  last 
  whorl, 
  as 
  in 
  several 
  other 
  species. 
  They 
  

   are 
  also 
  more 
  vividly 
  colored. 
  Some 
  extreme 
  examples 
  of 
  this 
  

   kind 
  might 
  at 
  first 
  be 
  supposed 
  to 
  belong 
  to 
  a 
  distinct 
  species 
  ; 
  

   but 
  the 
  intermediate 
  examples 
  are 
  far 
  more 
  numerous, 
  showing 
  

  

  