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XXXIV.  On  the  Organization  of  the  Brachiopoda. 
By  Albany  Hancock,  Esq.  Communicated  hy  T.  H.  Huxley,  Esg.^  F.R.S. 
Eeceived  April  24, — Bead  May  14,  1857. 
Having  been  engaged  for  some  time  past  in  the  investigation  of  the  anatomy  of  the 
Brachiopods,  I beg  to  lay  before  the  Boyal  Society  the  results  of  my  labours ; and  I am 
the  more  anxious  to  do  so  as  some  differences  of  opinion  have  arisen  among  naturalists 
respecting  the  structure  of  these  interesting  animals. 
Four  years  ago  I had  occasion  to  dissect  Waldheimia  australis,  Terehratulina  caput- 
serpentis  and  Lingula  anatina,  and  was  then  struck  with  the  peculiar  appearance  of 
the  organs  denominated  hearts  by  Baron  Cuvier,  Professor  Owen,  and  all  subsequent 
vwiters  on  the  subject.  These  so-called  hearts  seemed  to  me  very  unlike  any  molluscan 
heart  that  had  ever  come  under  my  observation ; and  on  attentive  examination  it  became 
evident  that  they  give  off  no  arteries  as  they  had  been  described  to  do ; and  moreover 
that  their  apices,  from  which  the  arteries  were  stated  to  pass,  appeared  to  open  exter- 
nally. For  these,  and  for  other  reasons,  I rras  inclined  to  disbelieve  in  their  cardiac 
nature,  and  to  regard  them  rather  as  oHducts. 
I examined  at  the  same  time,  with,  considerable  care,  the  alimentary  tube  of  the  Tere- 
bratulidce,  my  attention  having  been  particularly  drawn  to  this  matter  by  Mr.  Wood- 
ward, who  pointed  out  that  the  intestine  appeared  to  him  to  terminate,  not  as  described 
by  Professor  Owen,  but  within  the  visceral  chamber.  I found  this  to  be  the  case  ; and 
though  I failed  to  demonstrate  an  anal  outlet,  yet  was  disposed  to  believe  in  the  exist- 
ence of  a minute  anal  puncture,  and  thought  the  refuse  of  digestion  might  possibly 
make  its  escape  by  the  foramen  of  the  peduncle.  However  this  might  be,  it  was  quite 
ob\ious  that  no  anal  aperture  was  situated  in  the  palhal  chamber  in  the  two  species 
examined.  In  Lingula,  indeed,  the  anus  was  easily  observed,  placed  at  the  right  side, 
between  the  margins  of  the  mantle.  I also  examined  the  muscular  apparatus,  and  like- 
wise the  nervous  system;  and  the  complicated  structure  of  the  mantle  was  found  to 
inHte  further  investigation. 
Other  and  more  urgent  matters,  however,  at  that  time  claimed  my  attention,  and  all 
further  inquiry  into  the  structure  of  the  Brachiopods  was  necessarily  deferred.  The 
results  obtained  were  nevertheless  partially  made  known,  and  have  to  a considerable 
extent  been  substantiated  by  the  more  recent  investigations  of  Professor  Huxley,  who 
in  1864  published  a very  important  paper  on  the  anatomy  of  the  Brachiopods,  in  the 
‘ Proceedings  of  the  Boyal  Society.’  In  this  paper  the  author  arrives  at  the  conclusion 
that  in  Waldheimia  and  Rhynchonella  there  is  no  anus  at  all ; but  that  the  intestine 
MDCCCLVIII.  5 L 
