﻿428 
  Dr. 
  D. 
  Ferrier 
  on 
  the 
  Brain 
  of 
  Monkeys. 
  

  

  their 
  being 
  on 
  the 
  same 
  side 
  as 
  the 
  stimulation, 
  is 
  explained 
  by 
  the 
  origin 
  

   of 
  the 
  olfactory 
  tract 
  from 
  the 
  subiculum 
  cornu 
  ammonis, 
  and 
  which 
  passes 
  

   on 
  to 
  the 
  olfactory 
  bulb 
  without 
  decussation. 
  

  

  The 
  results 
  plainly 
  indicate 
  a 
  perception 
  or 
  subjective 
  sensation 
  of 
  

   odours, 
  and 
  point 
  to 
  this 
  as 
  the 
  central 
  seat 
  of 
  the 
  sense 
  of 
  smell. 
  

  

  Occipital 
  lobes 
  (superior 
  and 
  middle 
  convolutions). 
  

  

  These 
  were 
  experimented 
  on 
  in 
  I., 
  III., 
  V., 
  VII., 
  VIII., 
  IX., 
  X., 
  XI., 
  

   and 
  XII. 
  ; 
  also 
  in 
  another, 
  not 
  numbered, 
  on 
  November 
  21. 
  

  

  The 
  results, 
  except 
  in 
  the 
  case 
  of 
  X., 
  to 
  be 
  afterwards 
  mentioned, 
  

   were 
  altogether 
  negative 
  as 
  far 
  as 
  outward 
  phenomena 
  were 
  concerned. 
  

  

  The 
  negative 
  results 
  are 
  not 
  to 
  be 
  attributed 
  to 
  exhaustion 
  of 
  the 
  

   excitability 
  of 
  the 
  brain, 
  for 
  the 
  other 
  centres 
  at 
  the 
  same 
  time 
  gave 
  the 
  

   usual 
  results. 
  

  

  In 
  the 
  case 
  of 
  X. 
  it 
  was 
  observed 
  that 
  stimulation 
  of 
  the 
  inferior 
  occi- 
  

   pital 
  convolution 
  towards 
  its 
  inner 
  aspect 
  caused 
  uneasy 
  movements 
  in 
  

   the 
  hind 
  legs 
  and 
  tail, 
  the 
  head 
  being 
  turned 
  to 
  the 
  left 
  (opposite 
  side) 
  

   and 
  backwards. 
  Occasionally 
  also 
  a 
  plaintive 
  cry, 
  as 
  if 
  from 
  annoyance, 
  

   was 
  uttered. 
  On 
  cessation 
  of 
  the 
  irritation 
  the 
  animal 
  subsided 
  into 
  its 
  

   dozing 
  state. 
  

  

  Possibly 
  the 
  result 
  may 
  be 
  attributed 
  to 
  conduction 
  of 
  the 
  current 
  to 
  

   the 
  tentorium 
  or 
  other 
  part 
  of 
  the 
  dura 
  mater 
  ; 
  but, 
  owing 
  to 
  the 
  diffi- 
  

   culty 
  of 
  reaching 
  this 
  part 
  of 
  the 
  brain, 
  it 
  is 
  not 
  easy 
  to 
  avoid 
  all 
  sources 
  

   of 
  fallacy. 
  

  

  Marginal 
  convolution. 
  

  

  In 
  the 
  case 
  of 
  IX., 
  the 
  only 
  one 
  explored, 
  it 
  was 
  found 
  that 
  irritation 
  

   of 
  the 
  median 
  aspects 
  of 
  the 
  frontal 
  and 
  parietal 
  convolutions 
  caused 
  

   movements 
  of 
  the 
  head 
  and 
  limbs 
  similar 
  to 
  those 
  caused 
  by 
  stimulation 
  

   of 
  the 
  centres 
  on 
  the 
  outer 
  aspect 
  of 
  the 
  hemisphere. 
  

  

  Gyrus 
  fornicatus. 
  

  

  No 
  results 
  were 
  made 
  out 
  on 
  slipping 
  the 
  electrodes 
  deeply 
  between 
  

   the 
  hemispheres. 
  

  

  Corpus 
  callosum. 
  

  

  Stimulation 
  of 
  this 
  was 
  likewise 
  unattended 
  by 
  any 
  outward 
  result. 
  

  

  These 
  complete 
  the 
  regions 
  which 
  I 
  have 
  as 
  yet 
  been 
  able 
  to 
  succeed 
  in 
  

   experimenting 
  on. 
  

  

  I 
  now 
  pass 
  from 
  experiments 
  on 
  the 
  hemispheres 
  to 
  similar 
  experiments 
  

   on 
  the 
  basal 
  ganglia. 
  These 
  were 
  reached 
  in 
  a 
  few 
  cases 
  by 
  division 
  of 
  

   the 
  corpus 
  callosum, 
  turning 
  out 
  the 
  hemisphere 
  partially, 
  and 
  thus 
  lay- 
  

   ing 
  open 
  the 
  interior 
  of 
  the 
  lateral 
  ventricle. 
  

  

  Corpus 
  striatum. 
  

  

  The 
  corpus 
  striatum 
  was 
  laid 
  bare 
  and 
  stimulated 
  in 
  VIII. 
  and 
  XIII. 
  

  

  