In  a  case  recorded  by  Pfliiger  there  were  periodical  attacks  of  paralysis  of  variable  seat ;
of  the  left  third  and  facial  nerves  at  eighteen,  of  the  nerves  on  the  right  side  at  twenty,  of
the  left  third  neive  again  at  twenty-two,  and  six  months  later  of  the  left  sixth  and  facial.
Each  attack  lasted  from  one  to  two  months,  and  was  preceded  by  pain,  which  before  the  last
was  about  the  left  mastoid  process.
616  CRANIAL   NERVES.
The  nerve  appeared  gray,  and  its  roots  were  surrounded  by  small  gray
granulations  which  contained  tubercular  bacilli,  which  did  not  extend  into
the  crus.  Some  fatty  degeneration  was  found  in  the  muscles  supplied  by  it,
the  other  muscles  being  normal.
.  NUCLEAR  OCULAR  PALSY.
Disease  of  the  nuclei,  third,  fourth  and  sixth,  are  frequent  causes  of
paralysis  of  the  eye  muscles,  internal  and  external.  The  symptoms  vary
much  according  to  the  position  and  character  of  the  disease.  The  nuclei
riiay  be  the  seat  of  various  lesions,  acute  and  chronic.  The  isolated  affection  of
the  sixth  nucleus  has  already  been  considered  in  the  account  of  the  conjugate
palsy  which  such  disease  produces.  The  nucleus  of  the  fourth  nerve  may  be
regarded  as  part  of  the  third.  We  have,  therefore,  only  now  to  consider  the
lesions  of  the  third  nucleus,  together  with  those  of  the  sixth  nucleus,  in  so
far  as  it  is  associated  with  the  third  in  primary  degeneration.  Some  of  the
symptoms  of  nuclear  disease  have  already  been  described,  and  need  only  be
enumerated  here  to  complete  the  account  of  the  subject.
