﻿456 
  Panama 
  Shells. 
  calyptr^id^. 
  

  

  Deshayes 
  observes 
  that 
  he 
  can 
  hardly 
  tliink 
  that 
  the 
  shell 
  

   figured 
  as 
  Calyptrma 
  unguiformis 
  by 
  Broderip 
  in 
  ' 
  Trans. 
  Zool. 
  

   Soc.' 
  I. 
  pi. 
  29, 
  f. 
  4, 
  is 
  the 
  shell 
  of 
  Linnasus. 
  He 
  says 
  the 
  shell 
  

   of 
  Linnoeus 
  is 
  distinguished 
  by 
  a 
  profound 
  notch 
  at 
  one 
  

   extremity 
  of 
  the 
  partition, 
  and 
  a 
  feebler 
  one 
  at 
  the 
  other 
  ; 
  that 
  

   the 
  shell 
  described 
  by 
  Mr. 
  Say 
  as 
  Crejiidula 
  plana 
  wants 
  this 
  

   notch, 
  and 
  is 
  the 
  shell 
  figured 
  by 
  Broderip. 
  Now 
  it 
  so 
  happens 
  

   that 
  the 
  only 
  specimen 
  which 
  I 
  am 
  certain 
  is 
  entire, 
  has 
  this 
  

   notch 
  precisely 
  as 
  described, 
  and 
  the 
  tooth-like 
  process 
  which 
  

   separates 
  the 
  large 
  notch 
  from 
  the 
  rest 
  of 
  the 
  margin 
  is 
  such 
  as 
  

   would 
  be 
  likely 
  to 
  be 
  broken 
  in 
  almost 
  every 
  instance. 
  This 
  

   fact 
  leads 
  me 
  to 
  suppose 
  that 
  all 
  three 
  of 
  the 
  shells 
  in 
  question 
  

   are 
  of 
  the 
  same 
  species, 
  and 
  should 
  be 
  called 
  C. 
  unguiformis,^'' 
  

  

  jStation. 
  — 
  Dans 
  I'interieur 
  des 
  coquilles 
  univalves 
  abandonnees; 
  

   Defrance. 
  Espece 
  qui 
  a 
  1 
  'habitude 
  de 
  se 
  mettre 
  a 
  I'abri 
  dans 
  

   les 
  coquilles 
  abandonndes 
  ; 
  Deshayes. 
  Inside 
  of 
  dead 
  shells 
  of 
  

   Ranella 
  vexillum, 
  R. 
  ccdata^ 
  &c. 
  * 
  * 
  * 
  Dredged 
  from 
  sandy 
  mud 
  

   at 
  a 
  depth 
  ranging 
  from 
  4 
  to 
  10 
  fathoms 
  ; 
  Cuming 
  ! 
  Broderip. 
  In 
  

   the 
  aperture 
  of 
  other 
  shells 
  ; 
  Gould 
  ! 
  In 
  dead 
  shells, 
  whether 
  

   or 
  not 
  the 
  shells 
  are 
  occupied 
  by 
  Paguridag. 
  We 
  have 
  received 
  

   the 
  shell 
  from 
  Sicily 
  in 
  the 
  aperture 
  of 
  a 
  Murex 
  trunculus. 
  In 
  

   Massachusetts 
  we 
  have 
  found 
  it 
  in 
  the 
  aperture 
  of 
  Natica 
  dupli- 
  

   cata^ 
  of 
  Pyrula 
  canaliculata, 
  P. 
  carica.; 
  on 
  the 
  inside 
  of 
  Pecten 
  

   concentricits, 
  and 
  of 
  the 
  crustacean 
  Limulus 
  polyphemus^ 
  &c. 
  

   In 
  Jamaica, 
  we 
  found 
  it 
  in 
  Murex 
  hrevifrons^ 
  M. 
  funiculatus 
  (?), 
  

   Fasciolaria 
  tulipa, 
  Pyrula 
  melongena, 
  Turbo 
  crenulatus^ 
  &c. 
  

   In 
  Panama 
  we 
  found 
  it 
  in 
  Murex 
  radix^ 
  Fasciolaria 
  granosa^ 
  

   Turbo 
  saxosus, 
  Natica 
  sp. 
  indet., 
  &c. 
  It 
  occurs 
  more 
  frequently 
  

   near 
  half 
  tide 
  level, 
  but 
  is 
  not 
  very 
  narrowly 
  limited 
  in 
  its 
  ver- 
  

   tical 
  range. 
  

  

  Dr. 
  Gould 
  and 
  D'Orbigny 
  both 
  consider 
  the 
  peculiarities 
  of 
  

   this 
  shell 
  as 
  the 
  effect 
  of 
  its 
  position 
  ; 
  and 
  Orbigny 
  ascribes 
  the 
  

   flattened 
  form 
  to 
  the 
  pressure 
  of 
  the 
  organs 
  of 
  hermit 
  crabs, 
  

   one 
  of 
  which 
  usually 
  occupies 
  the 
  same 
  habitation. 
  If, 
  however, 
  

  

  