﻿VITRINELLA. 
  Panama 
  Shells. 
  411 
  

  

  more 
  than 
  three, 
  convex 
  above 
  and 
  concave 
  below 
  the 
  middle, 
  

   with 
  a 
  distinct 
  suture 
  : 
  aperture 
  orbicular 
  : 
  labrum 
  angulated 
  

   externally 
  by 
  the 
  spiral 
  ridges, 
  a 
  little 
  thickened 
  : 
  umbilicus 
  

   deep, 
  narrow. 
  A 
  variety 
  has 
  the 
  ridge 
  around 
  the 
  umbilicus 
  

   well 
  developed. 
  

  

  Mean 
  divergence 
  about 
  160° 
  ; 
  greatest 
  breadth 
  .07 
  inch 
  ; 
  

   least 
  breadth 
  .06 
  inch 
  ; 
  height 
  .04 
  inch. 
  

  

  Station. 
  — 
  Unknown. 
  

  

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

  

  24 
  specimens 
  were 
  found 
  in 
  the 
  calcareous 
  sand, 
  

  

  264, 
  Vitriiiella 
  parTa. 
  Nov. 
  sp. 
  

  

  Shell 
  subdiscoidal 
  : 
  white 
  : 
  with 
  numerous 
  stout 
  prominent 
  

   transverse 
  ribs 
  ; 
  with, 
  on 
  each 
  side 
  of 
  the 
  periphery 
  of 
  the 
  last 
  

   whorl, 
  a 
  not 
  very 
  prominent 
  keel, 
  of 
  which 
  the 
  upper 
  one 
  is 
  

   visible 
  on 
  the 
  spire 
  : 
  apex 
  very 
  obtuse 
  : 
  spire 
  convex, 
  slightly 
  

   elevated 
  : 
  whorls 
  three 
  and 
  a 
  half, 
  angular 
  above, 
  concave 
  

   between 
  the 
  angle 
  and 
  the 
  keel, 
  with 
  the 
  suture 
  not 
  very 
  dis- 
  

   tinct 
  ; 
  last 
  whorl 
  very 
  large 
  : 
  aperture 
  orbicular, 
  very 
  oblique 
  

   in 
  consequence 
  of 
  the 
  advance 
  of 
  the 
  labrum 
  above 
  : 
  lip 
  

   slightly 
  thickened 
  : 
  umbilicus 
  deep, 
  narrow. 
  This 
  species 
  

   resembles 
  V. 
  Panamensis. 
  

  

  Mean 
  divergence 
  about 
  160° 
  ; 
  greatest 
  breadth 
  .047 
  inch 
  ; 
  

   least 
  breadth 
  .04 
  inch 
  ; 
  height 
  .026 
  inch. 
  

  

  Station, 
  — 
  Unknown. 
  

  

  Habitat 
  — 
  Panama 
  ; 
  C. 
  B. 
  A. 
  ! 
  

  

  13 
  specimens 
  were 
  found 
  in 
  the 
  calcareous 
  sand, 
  

  

  265. 
  Vitrinella 
  pcrparva. 
  Nov. 
  sp. 
  

  

  Shell 
  subdiscoidal 
  : 
  white 
  : 
  with 
  a 
  very 
  prominent 
  acute 
  

   spiral 
  keel 
  on 
  each 
  side 
  of 
  the 
  periphery 
  of 
  the 
  last 
  whorl, 
  and 
  

   a 
  less 
  prominent 
  one 
  around 
  the 
  umbilicus; 
  with 
  transverse 
  

  

  