﻿The 
  Relation 
  of 
  Spermatozoa 
  to 
  Certain 
  Electrolytes. 
  149 
  

  

  spermatozoa 
  or 
  eggs 
  stain 
  bright 
  red 
  with 
  neutral 
  red, 
  whereas 
  sea 
  water 
  

   gives 
  an 
  orange 
  reaction 
  with 
  this 
  indicator. 
  Finally, 
  living 
  spermatozoa 
  

   migrate 
  to 
  the 
  positive 
  pole 
  of 
  an 
  electric 
  field. 
  We 
  therefore 
  start 
  from 
  the 
  

   assumption 
  that 
  spermatozoa 
  resemble 
  a 
  suspension 
  of 
  colloid 
  particles 
  in 
  an 
  

   alkaline 
  medium. 
  It 
  is 
  maintained 
  that 
  the 
  experiments 
  to 
  be 
  described 
  

   afford 
  strong 
  support 
  for 
  this 
  hypothesis. 
  

  

  The 
  Effects 
  of 
  Trivalent 
  Positive 
  Ions. 
  

  

  A 
  concentration 
  of 
  0*0005 
  M 
  CeCLj 
  or 
  La(N03)3 
  in 
  sea 
  water 
  quickly 
  

   causes 
  most 
  marked 
  agglutination 
  of 
  a 
  sperm 
  suspension. 
  The 
  spermatozoa 
  

   are 
  heaped 
  together 
  in 
  irregular 
  masses 
  clearly 
  visible 
  to 
  the 
  naked 
  eye. 
  

   These 
  masses 
  quickly 
  sink 
  to 
  the 
  bottom 
  of 
  the 
  tube 
  containing 
  the 
  

   suspension. 
  If 
  the 
  agglutinated 
  spermatozoa 
  are 
  gently 
  centrifuged 
  and 
  

   washed 
  with 
  normal 
  sea 
  water 
  little 
  or 
  no 
  change 
  takes 
  place 
  in 
  their 
  

   appearance 
  even 
  after 
  fairly 
  strong 
  agitation. 
  » 
  

  

  If, 
  however, 
  to 
  10 
  c.c. 
  of 
  sea 
  water 
  containing 
  agglutinated 
  spermatozoa 
  

   1 
  c.c. 
  of 
  0*8 
  M* 
  sodium 
  citrate 
  is 
  added, 
  all 
  trace 
  of 
  agglutination 
  rapidly 
  

   disappears, 
  and 
  the 
  fluid 
  again 
  resembles 
  the 
  original 
  dispersed 
  sperm 
  

   suspension. 
  The 
  phenomena 
  are 
  very 
  striking 
  with 
  both 
  cerium 
  and 
  sodium 
  

   -citrate 
  solutions. 
  Similar 
  experiments 
  were 
  performed 
  with 
  lanthanum 
  and 
  

   •thorium 
  nitrates. 
  

  

  Table 
  III. 
  

  

  Mol. 
  cone, 
  of 
  cerium. 
  

  

  Degree 
  of 
  flocculation. 
  

  

  

  

  

  

  -00025 
  

  

  + 
  + 
  

  

  0-0005 
  

  

  + 
  + 
  + 
  

  

  -00075 
  

  

  + 
  + 
  + 
  

  

  0010 
  

  

  + 
  + 
  + 
  

  

  -00125 
  

  

  + 
  + 
  + 
  

  

  Note. 
  — 
  In 
  the 
  above 
  and 
  subsequent 
  tables 
  the 
  following 
  symbols 
  will 
  be 
  used 
  : 
  — 
  

   represents 
  a 
  suspension 
  of 
  maximum 
  dispersal. 
  

  

  + 
  + 
  + 
  represents 
  a 
  suspension 
  of 
  maximum 
  agglutination 
  which 
  quickly 
  settles 
  to 
  the 
  

   bottom 
  of 
  the 
  fluid. 
  

  

  + 
  + 
  represents 
  a 
  suspension 
  in 
  which 
  the 
  agglutination 
  is 
  well 
  marked, 
  but 
  settles 
  

   somewhat 
  slowly. 
  

  

  + 
  represents 
  a 
  suspension 
  in 
  which 
  agglutination 
  is 
  still 
  visible 
  to 
  the 
  naked 
  eye, 
  but 
  

  

  which 
  settles 
  very 
  slowly. 
  

   very 
  faint 
  indication 
  of 
  agglutination. 
  

  

  It 
  will 
  be 
  noted 
  that 
  these 
  experiments 
  are 
  an 
  exact 
  parallel 
  to 
  those 
  which 
  

   can 
  be 
  performed 
  with 
  a 
  suspension 
  of 
  albumen 
  or 
  globulin 
  in 
  slightly 
  

  

  * 
  A 
  solution 
  of 
  this 
  strength 
  depresses 
  the 
  freezing 
  point 
  of 
  water 
  to 
  approximately 
  

   that 
  of 
  sea 
  water. 
  

  

  