t  A  view  of  the  Ileo-coecal  valve  as  it  appears  in  the  dried  intestine,  b,  The
upper  segment  of  the  valve,  orilio-colic  as  it  might  be  called,  which  is  horizon-
tal, a,  The  lower  or  ileo-ccecal  forms  an  inclined  plane  of  about  45°,  and  both
are  parabolic,  c,  The  closed  end  of  the  cascum,  d,  Ascending  colon  tied  and
cut  off  near  its  middle,  e.  Ilium  opening  into  the  colon,  through  the  valve.
/,  Appendicula  vermiformis.
POSITION   OF    THE    RECTUM.  57

tines  at  their  place  of  junction,  and  this  structure  is  then
examined  from  withoxit,  it  appears  as  if  a  transverse  or  half
circular  indentation  had  been  formed  by  the  villous  coat  of  the
great  intestine,  and  that  the  internal  coat  of  the  extremity  of
the  ileum  was  pressed  into  this  indentation,  and  united  to  the
internal  coat  of  the  great  intestine  which  formed  it ;  while  there
was  a  slit  both  in  the  indentation  and  in  the  end  of  the  ileum,
which  formed  a  communication  between  the  cavity  of  the  great
intestine  and  the  ileum.  The  longitudinal  fibres  of  both  intes-
tines, as  well  as  their  external  coats,  seemed  to  be  united,  so  as
to  form  a  common  cover  for  them  ;  while  the  circular  fibres
were  blended  in  the  two  portions  of  the  indentation  which  form
the  lips  of  the  orifice.
