﻿KISSOA. 
  Panama 
  Shells. 
  401 
  

  

  remote 
  a 
  latitude 
  as 
  Chiloe. 
  Dr. 
  Pliilippi 
  has, 
  therefore, 
  with 
  

   much 
  reason, 
  quoted 
  with 
  doubt 
  the 
  statement 
  of 
  M. 
  Petit. 
  

  

  243. 
  Rissoa 
  claiiclestina. 
  Nov. 
  sp. 
  

  

  Shell 
  long, 
  ovate 
  conic 
  : 
  dingy 
  white 
  : 
  with, 
  on 
  each 
  whorl, 
  

   about 
  eighteen 
  or 
  nineteen 
  stout 
  prominent 
  compressed 
  ribs, 
  

   which 
  are 
  continued 
  to 
  the 
  anterior 
  extremity 
  : 
  apex 
  acute 
  : 
  

   spire 
  with 
  the 
  outlines 
  moderately 
  curvilinear 
  : 
  whorls 
  seven, 
  

   moderately 
  convex 
  : 
  with 
  a 
  well 
  impressed 
  suture 
  : 
  last 
  whorl 
  

   rather 
  large 
  : 
  aperture 
  large, 
  oblique, 
  moderately 
  effuse 
  at 
  both 
  

   extremities 
  : 
  labrum 
  much 
  advanced 
  along 
  the 
  middle, 
  much 
  

   thickened 
  with 
  a 
  broad 
  varix 
  : 
  umbilicus 
  wanting. 
  

  

  Mean 
  divergence 
  about 
  30° 
  ; 
  length 
  .115 
  inch 
  ; 
  breadth 
  .05 
  

   inch 
  ; 
  length 
  of 
  spire 
  .07 
  inch. 
  

  

  Station. 
  — 
  Unknown. 
  

  

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

   2 
  specimens 
  were 
  found. 
  

  

  244. 
  Ri^^soa 
  firoiata. 
  Nov. 
  sp. 
  

  

  Shell 
  long, 
  ovate 
  conic 
  : 
  dingy 
  white 
  : 
  with, 
  on 
  each 
  whorl, 
  

   about 
  twelve 
  very 
  stout, 
  prominent, 
  rather 
  acute 
  ribs, 
  which 
  

   are 
  continued 
  to 
  the 
  anterior 
  extremity 
  : 
  apex 
  acute 
  : 
  spire 
  with 
  

   the 
  outlines 
  curvilinear: 
  whorls 
  seven, 
  convex, 
  with 
  a 
  well 
  

   impressed 
  suture 
  : 
  last 
  whorl 
  rather 
  large 
  : 
  aperture 
  oblique, 
  

   subovate, 
  effuse 
  at 
  both 
  extremities 
  : 
  labrum 
  well 
  advanced 
  

   along 
  the 
  middle, 
  thickened 
  with 
  a 
  broad 
  stout 
  rib 
  : 
  umbilicus 
  

   wanting. 
  

  

  Mean 
  divergence 
  about 
  30° 
  ; 
  length 
  .185 
  inch 
  ; 
  breadth 
  .075 
  

   inch 
  ; 
  length 
  of 
  spire 
  .13 
  inch. 
  

  

  Station. 
  — 
  Unknown. 
  

  

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

  

  1 
  specimen 
  was 
  found 
  in 
  the 
  sand. 
  

  

  