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  underground 
  parts 
  of 
  a 
  great 
  variety 
  of 
  crops, 
  including 
  sugar 
  beets^ 
  

   being, 
  like 
  the 
  wireworms, 
  most 
  destructive 
  the 
  second 
  year 
  after 
  grass. 
  

   They 
  eat 
  the 
  smaller 
  roots, 
  destroy 
  the 
  tap-root 
  of 
  the 
  plant, 
  or 
  gnaw 
  

  

  Fig. 
  95. 
  A 
  June-bug 
  larva 
  

   or 
  White 
  Grub, 
  I.aclniosterna 
  

   rugosa. 
  

  

  97. 
  A 
  June-bug. 
  Laclinostcrita 
  rugosa, 
  adult; 
  

   <i, 
  last 
  segments 
  of 
  male, 
  from 
  beneath. 
  

  

  large 
  cavities 
  in 
  the 
  substance 
  of 
  the 
  beet 
  — 
  injuries 
  frequently 
  indicated 
  

   by 
  the 
  sudden' 
  wilting 
  of 
  the 
  leaves. 
  In 
  a 
  Nebraska 
  field 
  of 
  beets^ 
  

   planted 
  on 
  ground 
  which 
  had 
  lain 
  idle 
  for 
  a 
  few 
  years, 
  about 
  fifteen 
  per 
  

   cent, 
  of 
  the 
  plants 
  were 
  thus 
  destroyed.. 
  Grubs 
  of 
  Lacliiiosterna 
  nigosa 
  

   have 
  been 
  found 
  by 
  us 
  this 
  year 
  injuring 
  the 
  roots 
  of 
  beets 
  in 
  central 
  

   Illinois, 
  and 
  causing 
  the 
  plants 
  to 
  wilt. 
  

  

  The 
  white 
  grubs 
  common 
  in 
  this 
  state 
  are 
  elaborately 
  treated 
  in 
  

   the 
  Eighteenth 
  Report 
  of 
  the 
  State 
  Entomologist 
  of 
  Illinois, 
  to 
  which 
  

  

  reference 
  may 
  be 
  made 
  for 
  a 
  more 
  de- 
  

   tailed 
  account. 
  The 
  following 
  summary 
  

   of 
  the 
  life 
  history 
  will, 
  however, 
  be 
  useful 
  

   in 
  this 
  place. 
  

  

  The 
  eggs 
  are 
  transparent 
  white, 
  at 
  first 
  

   oblong-oval, 
  soon 
  becoming 
  nearly 
  spher- 
  

   ical. 
  They 
  are 
  deposited 
  in 
  the 
  earth, 
  

   one 
  to 
  three 
  inches 
  below 
  the 
  surface,^ 
  

   usually 
  some 
  time 
  in 
  June, 
  and 
  they 
  hatch 
  

   in 
  about 
  ten 
  to 
  eighteen 
  days. 
  The 
  young 
  

   larvee 
  feed 
  on 
  roots 
  during 
  the 
  remainder 
  of 
  the 
  season, 
  winter 
  over 
  

   deeper 
  in 
  the 
  ground, 
  and 
  come 
  up 
  and 
  resume 
  feeding 
  when 
  the 
  next 
  

   season 
  opens. 
  A 
  second 
  winter 
  is 
  passed 
  in 
  the 
  same 
  way, 
  and 
  in 
  June 
  

   and 
  July 
  of 
  the 
  third 
  season 
  they 
  form 
  oval 
  cells 
  in 
  the 
  earth, 
  and 
  in 
  

   late 
  summer 
  change 
  to 
  the 
  June 
  beetles. 
  These 
  beetles 
  do 
  not 
  usually 
  

   leave 
  their 
  cells 
  until 
  the 
  following 
  spring, 
  when 
  they 
  emerge, 
  pair 
  and 
  

   lay 
  their 
  eggs, 
  and 
  soon 
  die. 
  They 
  feed 
  during 
  their 
  short 
  life 
  on 
  the 
  

  

  Fig. 
  96. 
  A 
  June-bug 
  larva 
  or 
  White 
  

   Grub, 
  Lachnosterna 
  rugosa, 
  last 
  seg- 
  

   ment, 
  from 
  beneath. 
  

  

  