﻿CYRENA. 
  Panama 
  Shells. 
  499 
  

  

  449. 
  Artemis 
  saccata. 
  

  

  Synonymy. 
  

  

  Arthemis 
  saccata 
  Gould 
  in 
  Proc. 
  Bost. 
  Soc. 
  Nat. 
  Hist. 
  p. 
  91. 
  Nov. 
  1851. 
  

  

  Station. 
  — 
  Unknown. 
  

  

  Habitat. 
  — 
  Mazatlan 
  ; 
  Lt. 
  Green 
  ! 
  Gould. 
  

  

  Panama 
  ; 
  C. 
  B. 
  A. 
  ! 
  

   2 
  specimens 
  were 
  obtained. 
  

  

  450. 
  Oouldia 
  Pacifica. 
  Nov. 
  sp. 
  

  

  Shell 
  subtriangular, 
  but 
  with 
  the 
  ventral 
  margin 
  well 
  

   excurved 
  : 
  the 
  color 
  varying 
  in 
  different 
  specimens 
  from 
  dingy 
  

   white 
  to 
  pale 
  brown, 
  often 
  tinged 
  with 
  red 
  about 
  the 
  beaks, 
  

   with 
  some 
  narrow 
  rays 
  of 
  brown, 
  and 
  rarely 
  with 
  short 
  irregu- 
  

   lar 
  lines 
  of 
  brown 
  : 
  with 
  eight 
  to 
  twelve 
  stout 
  subequal 
  concen- 
  

   tric 
  ridges 
  : 
  sometimes 
  radiately 
  striated 
  : 
  beaks 
  very 
  acute 
  and 
  

   closely 
  approximate: 
  posterior 
  area 
  moderately 
  depressed: 
  

   lunule 
  defined 
  by 
  a 
  well 
  impressed 
  line, 
  rising 
  at 
  the 
  margin 
  of 
  

   the 
  valves 
  : 
  margin 
  of 
  the 
  interior 
  not 
  crenulate. 
  It 
  is 
  closely 
  

   allied 
  to 
  G. 
  parva 
  Ad. 
  

  

  Length 
  .22 
  inch 
  ; 
  height 
  .19 
  inch 
  ; 
  breadth 
  .09 
  inch. 
  

  

  Station 
  . 
  — 
  Unknown 
  . 
  

  

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

  

  We 
  collected 
  4 
  entire 
  shells 
  and 
  60 
  odd 
  valves. 
  

  

  451. 
  Cyrena 
  maritima. 
  Nov. 
  sp. 
  

  

  Shell 
  subtriangular, 
  but 
  with 
  the 
  ventral 
  margin 
  well 
  

   excurved, 
  ventricose, 
  thin 
  : 
  dingy 
  white, 
  more 
  or 
  less 
  viola- 
  

   ceous 
  in 
  the 
  posterior 
  half: 
  with 
  an 
  olivaceous 
  coarsely 
  striate 
  

   epidermis 
  : 
  with 
  well 
  impressed 
  strite 
  of 
  growth 
  : 
  beaks 
  very 
  

   prominent, 
  approximate 
  : 
  umbones 
  very 
  prominent 
  : 
  with 
  a 
  

   prominent 
  posterior 
  angle, 
  and 
  another 
  less 
  developed 
  posterior 
  

  

  