306 
MR.  BRODERIP  ON  THE  GENUS  CHAMA. 
Chama  spinosa. 
Tab.  XXXVIII.  Fig.  8  (Junior)  ;  9  (Senior). 
Chama  testa  alba  interdum  roseo  vel  purpurea  umbonem  versus  valves  superioris  pictd,  spinis 
fornicatis  creberrimis  horridd ;  intus  albd,  limbo  integro. 
Hob.  in  Oceano  Pacifico.    (Lord  Hood's  Island.) 
This  pretty  species  was  dredged  up  by  Mr.  Cuming  attached  to  corals  and  Aviculm  at 
a  depth  ranging  from  three  to  seven  fathoms. 
The  younger  specimens  are  tinged  towards  the  umbo  of  the  upper  valve  with  a  deU- 
cate  rose-colour.  The  umbo  of  the  lower  valve  is  often  produced  after  the  manner  of 
that  of  Chama  unicornis,  Lam. 
Chama  sordida. 
Tab.  XXXIX.  Fig.  8  (Junior) ;  9  (Senior). 
Chama  testa  albidd  subroseo  varid,  vel  totd  subrosed,  creberrime  striata,  hinc  et  hinc  foliaced ; 
intus  albd,  limbo  crenulato. 
Hab.  in  America  Centrali.    (Isle  of  Cuna.) 
This  species,  which  varies  much  according  to  its  age,  but  never  appears  to  grow  to  a 
large  size,  was  dredged  up  by  Mr.  Cuming  from  a  depth  of  eighteen  fathoms,  attached 
to  rocks. 
Old  specimens  have  the  lower  valve  often  very  much  produced. 
