ME.  HAJfCOCK  ON  THE  OEOANIZATION  OF  THE  BEACHIOPODA. 
809 
Fig.  3.  Side  view  of  the  same ; the  dorsal  pallial  lobe  divided  longitudinally,  and  one 
half  of  it  turned  back,  so  as  to  expose  the  pallial  chamber;  the  marginal 
setee  are  not  represented : — «,  «,  pallial  sinuses ; marginal  fold ; c,  liver  seen 
through  the  wall  of  the  perivisceral  chamber ; cl,  dorsal  ovaries ; e,  e,  intestine ; 
f,  lateral  wall  of  the  body,  or  perivisceral  chamber ; g,  anal  nipple ; h,  bra- 
chial apparatus ; ^,  cirri ; j,  adjustor  muscles ; Jc,  divaricators ; I,  anterior  wall 
of  body. 
Fig.  4.  View  of  the  walls  of  the  perhisceral  chamber  of  L.  anatma : — a,  posterior  parie- 
tal muscles ; h,  anterior  ditto ; c,  muscular  lining  of  anterior  wall ; d,  muscles 
in  connexion  with  the  gastro-parietal  bands ; e,  divaricators ; f,  root  of  (Eso- 
phagus ; g,  fold  of  anterior  wall  to  which  the  occlusors  are  adherent ; h,  two 
orifices  leading  from  the  permsceral  chamber  to  a cavity  situated  between 
the  bases  of  the  arms ; ^,  external  arteries  or  blood-channels  entering  ante- 
rior wall. 
Fig.  5.  Transverse  section  of  pallial  lobe  of  the  same : — ci,  marginal  fold ; h,  one  of  the 
setse ; c,  extreme  pallial  margin ; cl,  circumpallial  lacune ; e,  e,  peripheral  or 
outer  pallial  lacunes ; f,  ties  binding  the  walls  of  ditto  together ; g,  eg,  channels 
of  the  lateral  branches  of  the  great  pallial  sinus ; li,  channels  of  intermediate 
small  branches  of  ditto. 
Fig.  6.  Proximal  extremity  of  peduncle : — ci,  horny  sheath ; h,  muscular  cylinder  seen 
through  ditto ; c,  extremity  of  muscular  cylinder  or  peduncular  muscle ; 
d,  triangular  process  of  horny  sheath,  fitting  into  a corresponding  depression 
in  the  umbo  of  the  ventral  valve. 
Fig.  7.  The  same  extremity  of  peduncle,  with  the  horny  sheath  laid  open : — cl,  horny 
sheath ; h,  muscular  cylinder ; c,  c,  delicate  membrane  coating  ditto. 
Fig.  8.  Portion  of  the  wall  of  the  permsceral  chamber,  with  part  of  the  testis  adhering : 
— a,  wall  of  chamber ; h,  testis,  exhibiting  spermatophora  in  various  stages  of 
development. 
Fig.  9.  Three  spermatophora,  highly  magnified : — a,  a,  two  of  ditto,  apparently  fully 
developed,  containing  spermatozoa;  h,  one,  immature,  exhibiting  a double 
line  in  the  interior. 
Fig.  10.  Two  spermatophora,  in  an  early  state  of  development. 
