﻿470 
  Panama 
  Shells. 
  ostr^id^. 
  

  

  the 
  incremental 
  striae 
  : 
  nacre 
  extremely 
  brilliant, 
  with 
  delicate 
  

   changeable 
  colors. 
  

  

  Attached 
  to 
  ledges 
  of 
  rock 
  by 
  the 
  greater 
  part 
  of 
  the 
  lower 
  

   valve. 
  It 
  occurs 
  near 
  half 
  tide 
  level. 
  

  

  It 
  is 
  not 
  common 
  : 
  we 
  collected 
  only 
  3 
  specimens 
  on 
  the 
  reef 
  

   at 
  Panama. 
  

  

  382. 
  Ostrea 
  . 
  Sp. 
  indet. 
  c. 
  

  

  Synonymy. 
  

   ? 
  0. 
  ColumUensis 
  Hanley, 
  P. 
  Z. 
  S. 
  Lond. 
  p. 
  107, 
  Oct. 
  1845. 
  

  

  Eather 
  small, 
  more 
  or 
  less 
  pentangular, 
  and 
  short 
  but 
  not 
  

   plicated. 
  

  

  Attached 
  to 
  stones, 
  rocks, 
  and 
  other 
  shells, 
  near 
  half 
  tide 
  

   level 
  : 
  the 
  lower 
  valve 
  is 
  attached 
  by 
  rather 
  more 
  than 
  half 
  of 
  

   its 
  surface, 
  and 
  then 
  abruptly 
  rises 
  from 
  the 
  attached 
  part 
  so 
  as 
  

   to 
  form 
  a 
  deep 
  cavity. 
  

  

  0. 
  Columhiensis 
  Hani, 
  was 
  found 
  by 
  Mr. 
  Cuming 
  attached 
  to 
  

   rocks 
  at 
  half 
  tide 
  at 
  St. 
  Elena. 
  At 
  Panama 
  our 
  shell 
  is 
  not 
  

   rare, 
  although 
  we 
  took 
  only 
  15 
  specimens. 
  

  

  383. 
  Ostrea 
  . 
  Sp. 
  indet. 
  d. 
  

  

  Like 
  0. 
  horealis. 
  

  

  Usually 
  occurs 
  in 
  clusters. 
  

  

  It 
  was 
  brought 
  from 
  some 
  place 
  near 
  Panama 
  which 
  Ave 
  did 
  

   not 
  visit. 
  "We 
  obtained 
  35 
  specimens. 
  The 
  flavor 
  is 
  superior 
  

   to 
  that 
  of 
  0. 
  virginica 
  or 
  0. 
  horealis. 
  They 
  were 
  sold 
  in 
  Pa- 
  

   nama 
  at 
  a 
  dime 
  each. 
  

  

  384. 
  Ostrea 
  . 
  Sp. 
  indet. 
  e. 
  

  

  A 
  small 
  plicated 
  species. 
  The 
  animal 
  has 
  a 
  bitter 
  flavor. 
  

   Attached 
  to 
  rocks 
  and 
  stones 
  from 
  three 
  quarters 
  to 
  one 
  quar- 
  

   ter 
  tide 
  level. 
  A 
  small 
  var. 
  grows 
  on 
  Nerita 
  scahricosta. 
  

  

  This 
  species 
  covers 
  many 
  parts 
  of 
  the 
  reef 
  at 
  Panama 
  in 
  great 
  

   profusion. 
  We 
  collected 
  330 
  specimens. 
  

  

  