The  author  considers  historically  the  questlou  of  the  origin  of  nerfor-
atloK  ulcer  of  the  tout,  and  of  the  three  theories  as  tolls  oii^o,  the
mechanical,  iht^  vaitcular.  and  the  nervous  theories,  he  favors  the  Utter,
claiutlug  thkt  the  nervous  lesion  ia  always  pre«out,  while  the  Ta»cii)ar
(dianees  may  be  ahsenc.  Perforating  ulct^r  is  usually  considered  a  rare
complication  In  Keoeral  paralysis,  but  Bcrth*'leuiy  claims  that  It  is  not
so  rare  as  Is  supposed,  and  that  pohilnhM  observations  are  so  tew  be-
cause att<:utioD  luis  Qut  been  i^ultlcit-utly  tailed  to  tlic  condition,  and  he
U  able  to  present  eighteen  observations,  »11  from  French  sources,  foar
being  personal.  Id  two  cases  the  pHiicnlf  liad  autlcred  from  a  preced-
ing ^comotor  ataxia,  and  the  cniiibini-d  action  of  the  tabes  and  tbft
general  pamlyvis  producing  the  ulcer  is  admitted,  while  in  two  other
cases  alcnliollfni  waf>  doubttpi^s  a  Himilar  causal  factor,  but  In  the  re-
malnLus  fourteen  there  was  no  compHratlou,  and  the  general  paralysis
was  looked  on  as  the  tlircct  cnuee  of  the  ulcer,  A  striking  fact  brought
ont  In  the  ''tudy  ot  the  cafcs  wa^  tluit  In  eight  of  tlic  eighteen  caaes  It
was  noticed  that  under  the  evldc-nt  indueiicc  of  tlie  uk'er  andoubted
remission  occurred  to  the  counte  of  the  general  paralysis.  The
tame  tact  was  noted  by  Christian  In  publishing  his  observations  on
mat  ptr/orajU  la  188:2.  and  be  claimed  lliat  almost  all  reml»-
6lon«  In  general  paralysis  came  as  a  sequel  of  prolonged  suppura-
tions. I^rth^Iemy  suggests  that  such  remUiduus  followiog  ^up-
purationa  give  a  basUiorthe  ihcrapeutic  cniplnyment  ot  revulsive
uiea^ure^  puch  .ts  setons  In  the  neck  or  the  actual  cauterv.  The  author
reaches  the  same  general  conclusions  af  Maraudon  de  !UoDtyel  in  his
tbesla  of  1888:—].  I'rogres^ve  general  paralysis  is  as Jostly  a  c-aose  of
perforating  ulcer  »^  other  tUsoasei  of  the  nervous  system.  3.  Tlie
uifrequency  of  published  observations  on  perforating  ulcer  point  to
the  fact  that  the  compllcatioD  should  be  carefully  looked  for  to  be  dis-
covered, «nd  that  attention  has  not  been  sotn'cienilr  called  to  It.  3.
