﻿COLUMBELLA. 
  Panama 
  Shells. 
  309 
  

  

  In 
  Chenu, 
  the 
  figures 
  of 
  both 
  species 
  have 
  the 
  ribs 
  prolonged. 
  

   In 
  these 
  figures 
  the 
  ribs 
  are 
  more 
  distant 
  in 
  C. 
  costellata 
  than 
  in 
  

   G. 
  scalarina. 
  The 
  figure 
  of 
  the 
  former 
  very 
  exactly 
  represents 
  

   our 
  shells. 
  

  

  Station.' 
  — 
  A 
  single 
  specimen 
  was 
  found 
  at 
  the 
  depth 
  of 
  16 
  

   fathoms 
  : 
  Cumipg 
  ! 
  Sowerby. 
  Our 
  specimens 
  were 
  found 
  under 
  

   stones 
  near 
  low 
  water 
  mark. 
  

  

  Habitat. 
  — 
  Panama 
  ; 
  Cuming 
  ! 
  Sowerby 
  : 
  also 
  Miiller. 
  

  

  Panama 
  and 
  coast 
  of 
  Africa 
  ; 
  Gray. 
  

  

  Panama 
  ; 
  C. 
  B. 
  A. 
  ! 
  

   We 
  collected. 
  25 
  specimens 
  on 
  the 
  reef. 
  Mr. 
  Gray 
  must 
  be 
  

   in 
  error 
  when 
  he 
  includes 
  the 
  coast 
  of 
  Africa 
  in 
  the 
  habitat. 
  

  

  82. 
  Coliiiiibella 
  diniiniita. 
  Nov. 
  sp. 
  

  

  Shell 
  subfusiform 
  : 
  pale 
  yellowish 
  brown, 
  black 
  or 
  brownish 
  

   black 
  anteriorly 
  : 
  ribbed, 
  with 
  the 
  interstices 
  covered 
  with 
  spiral 
  

   striae, 
  which 
  are 
  coarser 
  anteriorly 
  where 
  the 
  ribs 
  are 
  obsolete 
  ; 
  

   apex 
  acute 
  : 
  spire 
  conic 
  : 
  whorls 
  seven, 
  scarcely 
  convex 
  : 
  with 
  

   the 
  suture 
  lightly 
  impressed 
  : 
  aperture 
  rather 
  narrow 
  : 
  labrum 
  

   variciform, 
  broadly 
  thickened, 
  sinuate 
  posteriorly, 
  crenulated 
  

   within 
  : 
  columellar 
  lip 
  with 
  the 
  granules 
  obsolete. 
  

  

  Mean 
  divergence 
  about 
  45° 
  ; 
  length, 
  .155 
  inch 
  ; 
  breadth, 
  .07 
  

   inch 
  ; 
  length 
  of 
  spire 
  .08 
  inch. 
  

  

  This 
  species 
  resembles 
  a 
  dwarfed 
  C. 
  nigrescens. 
  

  

  Station. 
  — 
  Under 
  stones 
  near 
  low 
  water 
  mark 
  we 
  found 
  this 
  

   shell. 
  

  

  Habitat. 
  — 
  Panama 
  ; 
  C. 
  B. 
  A. 
  ! 
  19 
  specimens 
  were 
  obtained. 
  

  

  83. 
  Coliitiibella 
  dorsata. 
  

  

  Synonymy. 
  

  

  Columbella 
  dorsata 
  Sowb. 
  in 
  Proc. 
  Zool.Soc. 
  Lond.p. 
  120. 
  June 
  1832. 
  

  

  Miiller 
  Synop. 
  Nov. 
  Test. 
  Viv. 
  p. 
  91. 
  May 
  1836. 
  

  

  Reeve 
  Conch. 
  Syst. 
  pi. 
  25 
  Y. 
  f. 
  Y. 
  1842. 
  

  

  