The  third  nuclei  are  occasionally  the  seat  of  hemorrhage,  of  softening,
and  of  morbid  growths.  They  are  said  to  be  sometimes  the  seat  of  acute
inflammation,  which  has  been  termed  "  acute  polio-encephalitis  superior."  *
The  most  frequent  lesion,  however,  is  slow,  progressive  degeneration.  It  is
this  that  is  the  cause  of  most  forms  of  progressive  ophthalmoplegia,  which  is
thus  a  synonym  for  nuclear  disease.  It  is,  indeed,  a  more  accurate  term,  for
we  do  not  yet  know  that  all  cases  which  seem  to  be  nuclear  are  really  so.f

Acute  Ophthalmoplegia  ;  Acute  Nuclear  Palsy. — Sudden  palsy  of  all  the
ocular  muscles  occurs  in  some  cases  of  hemorrhage  into  the  region  of  the
nuclei,  but  the  ocular  symptoms  are  usually  subordinate  to  those  of  apoplexy,
and  most  cases  are  quickly  fatal.  In  a  few  instances  recovery  has  taken
place,  and  palsy  of  the  third  nerves  has  usually  remained  partial.  It  is
probable  that  the  lesion  in  such  cases  has  generally  been  softening  from
disease  of  the  arteries  supplying  the  nuclei  with  blood.  J      It  has  been  con-

*By  Wernicke,  in  contradistinction  to  a  similar  affection  of  the  bulbar  »uclei,  which  has
been  termed  "polio-encephalitis  inferior."  It  is  an  inaccurate  name,  which'ought  not  to
come  into  use,  because,  if  any  meaning  is  attached  to  it,  it  should  be  that  of  inflammation  of
the  cortex.  As  a  matter  of  fact,  the  latter  has  been  termed  "  polio  encephalitis,"  and  yet  the
qualifying  "  superior  "  is  attached  to  a  lower  lesion.
•)-  An  able  summary  of  present  knowledge  on  the  subject  of  nuclear  palsy  has  been  published
by  Mauthner*  "  Vortrage,"  Heft  12,  1885.
