﻿147 
  

  

  The 
  Relation 
  of 
  Spermatozoa 
  to 
  certain 
  Electrolytes. 
  — 
  II. 
  

   By 
  J. 
  Gray, 
  M.A., 
  Fellow 
  of 
  King's 
  College, 
  Cambridge. 
  

  

  (Communicated 
  by 
  Prof. 
  J. 
  Stanley 
  Gardiner, 
  F.E.S. 
  Eeceived 
  October 
  24, 
  1919.) 
  

  

  The 
  fact 
  that 
  living 
  spermatozoa 
  move 
  towards 
  the 
  positive 
  pole 
  of 
  an 
  

   electric 
  field 
  has 
  been 
  known 
  for 
  some 
  years. 
  In 
  a 
  note 
  published 
  in 
  1915, 
  

   the 
  writer 
  (8) 
  pointed 
  out 
  that 
  this 
  movement 
  is 
  dependent 
  upon 
  a 
  certain 
  

   concentration 
  of 
  hydroxyl 
  ions, 
  without 
  which 
  the 
  spermatozoa 
  neither 
  

   exhibit 
  their 
  normal 
  activity 
  nor 
  do 
  they 
  move 
  in 
  an 
  electric 
  field. 
  In 
  the 
  

   same 
  paper 
  the 
  behaviour 
  of 
  spermatozoa 
  to 
  such 
  trivalent 
  ions 
  as 
  cerium 
  was 
  

   briefly 
  described. 
  In 
  the 
  present 
  communication 
  these 
  results 
  are 
  enlarged, 
  

   and 
  the 
  problem 
  briefly 
  discussed 
  from 
  its 
  theoretical 
  aspect. 
  

  

  A 
  considerable 
  mass 
  of 
  evidence 
  now 
  exists 
  to 
  show 
  that 
  the 
  surface 
  

   charge 
  of 
  a 
  particle 
  or 
  membrane 
  is 
  profoundly 
  affected 
  by 
  the 
  nature 
  of 
  the 
  

   solution 
  with 
  which 
  it 
  is 
  in 
  contact. 
  Albumen 
  particles, 
  when 
  suspended 
  in 
  

   an 
  acid 
  medium, 
  are 
  positively 
  charged 
  ; 
  when 
  in 
  an 
  alkaline 
  medium 
  they 
  

   are 
  negatively 
  charged. 
  Perrin 
  (11) 
  has 
  shown 
  that, 
  if 
  a 
  diaphragm 
  separates 
  

   two 
  phases 
  between 
  which 
  a 
  potential 
  gradient 
  exists, 
  then 
  the 
  gradient 
  

   can 
  increase 
  or 
  decrease 
  by 
  treating 
  the 
  diaphragm 
  with 
  various 
  agents. 
  In 
  

   acid 
  solutions 
  a 
  negative 
  diaphragm 
  becomes 
  less 
  negative, 
  and 
  finally 
  

   positive 
  ; 
  in 
  an 
  alkaline 
  solution 
  the 
  negative 
  charge 
  is 
  increased. 
  

  

  Table 
  I. 
  

  

  Diaphragm. 
  

  

  Solution. 
  

  

  Kelative 
  Charge. 
  

  

  Carborundum 
  (negative) 
  ... 
  

  

  -02M 
  HCI 
  

  

  + 
  10 
  

  

  O-O08M 
  HCI 
  

  

  

  

  

  0-002M 
  HCI 
  

  

  - 
  15 
  

  

  

  Water 
  

  

  - 
  50 
  

  

  

  -0002M 
  KOH 
  

  

  - 
  60 
  

  

  

  -002M 
  KOH 
  

  

  -105 
  

  

  Naphthalene 
  (negative) 
  ... 
  

  

  0-02M 
  HCI 
  

  

  + 
  38 
  

  

  0-01 
  HCI 
  

  

  + 
  39 
  

  

  

  0-001 
  HCI 
  

  

  + 
  28 
  

  

  

  0-0002 
  HCI 
  

  

  + 
  3 
  

  

  

  -0002 
  KOH 
  

  

  -29 
  

  

  

  0-001 
  KOH 
  

  

  -60 
  

  

  

  02 
  KOH 
  

  

  -60 
  

  

  It 
  should 
  be 
  noted 
  that 
  the 
  greatest 
  change 
  takes 
  place 
  round 
  the 
  neutral 
  

   point. 
  Perrin 
  also 
  investigated 
  the 
  effects 
  of 
  lanthanum 
  nitrate 
  upon 
  a 
  

   carborundum 
  membrane. 
  

  

  