﻿308 
  Panama 
  Shells. 
  PURPURID^. 
  

  

  cute 
  ; 
  spire 
  with 
  the 
  outlines 
  nearly 
  rectilinear 
  ; 
  whorls 
  eight, 
  

   convex, 
  with 
  a 
  moderately 
  impressed 
  suture 
  ; 
  last 
  whorl 
  sub- 
  

   angular 
  ; 
  aperture 
  a 
  little 
  wider 
  above 
  ; 
  labrum 
  moderately 
  

   thickened, 
  with 
  a 
  few 
  wrinkles 
  on 
  the 
  inside 
  : 
  notch 
  wide 
  and 
  

   deep. 
  

  

  Mean 
  divergence 
  about 
  35° 
  : 
  length 
  .21 
  inch 
  ; 
  breadth, 
  .1 
  inch 
  ; 
  

   length 
  of 
  spire, 
  .12 
  inch. 
  

  

  Station. 
  — 
  Unknown, 
  

  

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

  

  Only 
  one 
  specimen 
  of 
  this 
  elegant 
  shell 
  was 
  found. 
  

  

  81. 
  Coliiuibella 
  costellata. 
  

  

  Synonymy. 
  

  

  Columbella 
  costellata 
  Brocl. 
  and 
  Sowb. 
  in 
  Zool. 
  Journ. 
  

  

  IV. 
  376. 
  - 
  - 
  - 
  1829. 
  

  

  Sowb. 
  in 
  Proc. 
  Zool. 
  Soc, 
  Lond. 
  

  

  p. 
  118. 
  -------- 
  June 
  1832. 
  

  

  Miill. 
  Synops. 
  Nov. 
  Test. 
  Viv. 
  p. 
  88. 
  May 
  1836. 
  

  

  Gray 
  in 
  Zool. 
  Beech. 
  Voy. 
  pi. 
  36. 
  

  

  f. 
  9 
  ? 
  - 
  - 
  - 
  1839. 
  

  

  Duel, 
  in 
  Chenu 
  111. 
  Conch, 
  pi. 
  25. 
  f. 
  

  

  11, 
  12. 
  -------- 
  - 
  1843. 
  

  

  Sowb. 
  Thes. 
  Conch, 
  p. 
  137. 
  No. 
  79. 
  

  

  pi. 
  39. 
  f. 
  147. 
  - 
  - 
  1844. 
  

  

  We 
  have 
  had 
  some 
  difficulty 
  in 
  determining 
  whether 
  our 
  

   shells 
  belong 
  to 
  this 
  species 
  or 
  to 
  C. 
  scalarina. 
  Taking 
  the 
  

   descriptions 
  and 
  figures 
  by 
  Mr. 
  Sowerby, 
  the 
  ribs 
  in 
  C. 
  costellata 
  

   are 
  said 
  to 
  fall 
  far 
  short 
  of 
  the 
  anterior 
  extremity, 
  but 
  to 
  be 
  pro- 
  

   longed 
  in 
  G. 
  scalarina^ 
  although 
  the 
  figures 
  of 
  these 
  species 
  ex- 
  

   hibit 
  no 
  difference 
  in 
  this 
  respect 
  : 
  most 
  of 
  our 
  specimens 
  have 
  

   them 
  prolonged, 
  but 
  the 
  character 
  is 
  not 
  constant. 
  In 
  other 
  

   respects 
  the 
  figures 
  of 
  the 
  two 
  species 
  are 
  very 
  different, 
  and 
  

   that 
  of 
  C. 
  costellata 
  well 
  represents 
  our 
  shells. 
  Many 
  of 
  the 
  

   specimens 
  are 
  larger 
  than 
  this 
  figure. 
  

  

  