[    195  ] 
XXII.  Descriptions  of  some  new  Species  of  Calyptrseidse,    By  W.  J.  Broderip,  Esq., 
Vice-Pres.  of  the  Geological  and  Zoological  Societies,  F.R.S.,  L.S.,  ^c. 
Communicated  February  25  and  May  13,  1834. 
After  an  inspection  of  perhaps  the  largest  collection  of  Calyptraida  ever  brought 
together,  I  am  inclined  to  think  that  the  best  specific  characters  are  to  be  found  in  the 
markings  or  sculpture  of  the  external  shell,  in  the  shape  of  the  delicate  internal  chamber 
or  cup  {cyathus,  as  I  have  designated  it  in  Calyptrcea  and  Calypeopsis) ,  and  in  the  mode 
of  its  adhesion  to  the  inside  of  the  limpet-like  shell  which  contains  and  protects  it. 
External  form,  the  character  solely  relied  on  by  Lamarck,  varies  so  much,  according  to 
the  accidents  of  locality,  that  very  little  reliance  is  to  be  placed  upon  it ;  for  the  animal 
seems  to  accommodate  the  shell  entirely  to  the  circumstances  under  which  it  is  placed. 
I  have  before  me  specimens  taken  from  under  the  same  stone,  evidently  of  the  same 
species,  varying  in  shape  from  a  regular  high  cone  to  an  almost  flat  surface,  with  nearly 
every  intervening  irregularity  of  circumference  that  can  be  imagined.  Thus  much  I 
have  ventured  as  an  apology  for  not  laying  great  stress  on  that  which  satisfied  Lamarck, 
who  did  so  much  for  the  science  ;  but  when  it  is  remembered  that  he  has  only  described 
four  recent  and  two  fossil  species  of  Calyptraa  and  but  six  species  of  Crepidula,  it  will 
readily  occur  to  the  reader  that  he  had  not  the  opportunities  of  judging  of  the  value  of 
external  shape  which  the  rich  collection  brought  home  by  Mr.  Cuming  has  afforded  me. 
That  collection  contains  all  the  species  that  are  described  in  the  present  communication. 
M.  Deshayes  has  given  the  anatomy  of  Calyptrcea  Sinensis,  Lam.,  with  his  usual  ac- 
curacy; and  M.  Lesson,  in  the  '  Zoologie  de  la  Coquille,'  has  divided  the  Calyptraa;  and 
Crepidula  into  several  subgenera,  observing  that  it  is  immaterial  by  which  of  the  above- 
mentioned  names  the  leading  genus  is  known.  M.  Lesson  chooses  Calyptraa,  and  the 
following  arrangement  will  be  very  nearly  the  same  as  his,  though  it  may  be  necessary 
to  make  some  slight  alterations,  and  to  extend  the  definition  of  his  subgenus  Ca- 
lyptraa. 
M.  Lesson  has  founded  his  arrangement  upon  the  following  observations.  "  L'animal 
des  calyptrees  et  des  crepidules  nous  parait  ne  differer  en  rien  d'essentiel ;  et  quant  k 
la  cloison  du  test,  soit  que  cette  cloison  soit  transversale,  soit  qu'elle  ne  consiste  qu'en 
lamelles  annexees  au  fond  de  la  coquille,  elle  presente  des  passages  de  ces  deux  etats 
et  ne  pent  servir  qu'a  etablir  de  simples  sous-genres  au  grand  genre  calyptraa  ou  cre- 
pidula comme  on  voudra  I'appeler.  Voici  ce  que  nous  pensons  qu'on  pourrait  admettre 
dans  I'etat  actuel  de  nos  connaissances."^ 
VOL.  I. 
'  Zoologie  de  la  Coquille,  torn.  ii.  p.  388.  et  seq. 
2  D 
