﻿OCT. 
  4, 
  1922 
  STEINER 
  andheinly: 
  control 
  of 
  injurious 
  nemas 
  

  

  377 
  

  

  into 
  a 
  brownish, 
  or 
  even 
  apparently 
  black 
  organ. 
  To 
  this 
  end 
  the 
  

   presence 
  of 
  soil 
  was 
  absolutely 
  necessary. 
  In 
  water, 
  but 
  with 
  plenty 
  

   of 
  food 
  (other 
  small 
  larv^al 
  nematodes) 
  the 
  mononch 
  larv'ae 
  remained 
  

   transparent 
  and 
  died 
  in 
  a 
  short 
  time. 
  We 
  were 
  not 
  able 
  to 
  determine 
  

   exactly 
  what 
  kind 
  of 
  food 
  the 
  newly 
  hatched 
  and 
  very 
  young 
  larvae 
  

   ate. 
  They 
  moved 
  through 
  the 
  soil, 
  sucking 
  here 
  and 
  there 
  on 
  soil 
  

   fragments, 
  and 
  particles 
  of 
  an 
  organic 
  nature 
  were 
  probably 
  consumed. 
  

   But 
  the 
  mononch 
  larvae 
  soon 
  began 
  to 
  feed 
  on 
  other 
  nematodes. 
  

   We 
  observed 
  three-day 
  old 
  larvae 
  feeding 
  on 
  Rhabditis 
  larvae, 
  and 
  their 
  

   voracity 
  increased 
  with 
  their 
  age. 
  

  

  Our 
  records 
  showed 
  that 
  the 
  number 
  of 
  nematodes 
  killed 
  daily 
  in- 
  

  

  Fig. 
  3. 
  Photograph 
  of 
  the 
  dead 
  bodies 
  of 
  Rhabditis 
  elegans 
  Maupas 
  as 
  

   they 
  appeared 
  after 
  their 
  slaughter 
  by 
  mononchs. 
  The 
  picture 
  

   shows 
  well 
  the 
  common 
  method 
  of 
  destruction, 
  that 
  of 
  piercing 
  the 
  

   cuticle 
  and 
  sucking 
  the 
  contents 
  of 
  the 
  body 
  in 
  the 
  manner 
  of 
  a 
  

   weasel. 
  

  

  creased 
  as 
  the 
  mononch 
  developed, 
  beginning 
  with 
  one 
  or 
  two 
  destroyed 
  

   during 
  the 
  third 
  or 
  fourth 
  day 
  of 
  larval 
  life, 
  and 
  attaining 
  a 
  maximal 
  

   number 
  of 
  sixty 
  -five. 
  In 
  one 
  case 
  as 
  many 
  as 
  eighty- 
  three 
  Heterodera 
  

   radicicola 
  were 
  killed 
  (either 
  swallowed 
  wholly 
  or 
  partly 
  sucked 
  out) 
  

   by 
  one 
  mononch 
  in 
  one 
  day. 
  The 
  largest 
  amount 
  of 
  food 
  was 
  con- 
  

   sumed 
  at 
  the 
  time 
  the 
  maximal 
  number 
  of 
  eggs 
  was 
  produced, 
  and 
  

   then 
  it 
  decreased 
  during 
  the 
  senile 
  stage 
  of 
  life. 
  During 
  a 
  life 
  time 
  of 
  

   about 
  twelve 
  weeks 
  one 
  animal 
  killed 
  1332 
  nematodes. 
  We 
  are 
  certain 
  

  

  