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  The 
  beet 
  leaf-beetles 
  vary 
  in 
  size 
  from 
  small 
  to 
  minute. 
  The 
  wing- 
  

   covers 
  are 
  often 
  longitudinally 
  striped, 
  or 
  in 
  a 
  very 
  few 
  cases 
  spotted, 
  

   and 
  still 
  other 
  species, 
  especially 
  the 
  smaller 
  forms, 
  have 
  a 
  uniform 
  

   metallic 
  luster 
  — 
  bronze, 
  green, 
  or 
  black. 
  The 
  leaf-beetles 
  should 
  be 
  

   carefully 
  distinguished 
  from 
  the 
  beneficial 
  ladybugs 
  i^Coccinellidcc), 
  of 
  

   similar 
  form 
  and 
  size 
  and 
  also 
  often 
  abundant 
  upon 
  the 
  beet 
  leaves. 
  

   The 
  latter 
  have 
  wing-covers 
  either 
  plain 
  yellowish 
  or 
  spotted 
  with 
  black, 
  

   or, 
  in 
  the 
  smaller 
  forms, 
  plain 
  black, 
  often 
  with 
  red 
  or 
  white 
  spots. 
  

  

  The 
  leaf-beetles 
  commonly 
  riddle 
  the 
  leaf 
  with 
  small 
  holes, 
  and 
  if 
  

   abundant 
  may 
  seriously 
  injure 
  the 
  plant 
  or 
  even 
  destroy 
  the 
  crop 
  when 
  

   it 
  is 
  still 
  young. 
  Often 
  the 
  injury 
  does 
  not 
  extend 
  at 
  first 
  entirely 
  

   through 
  the 
  leaf, 
  the 
  epidermis 
  of 
  the 
  opposite 
  side 
  being 
  left 
  unbroken, 
  

   but 
  this 
  soon 
  shrivels 
  and 
  breaks 
  away 
  and 
  a 
  perforation 
  results. 
  This 
  

   is 
  usually 
  the 
  case 
  with 
  young 
  larvae 
  or 
  with 
  the 
  smaller 
  flea-beetles. 
  

   The 
  holes 
  made 
  by 
  the 
  cucumber 
  beetles 
  and 
  their 
  allies 
  (^Diabrotica) 
  

   are 
  more 
  irregular 
  than 
  those 
  made 
  by 
  flea-beetles, 
  the 
  latter 
  being 
  

   small 
  and 
  approximately 
  circular. 
  If 
  the 
  injured 
  leaf 
  be 
  young 
  the 
  

   holes 
  increase 
  with 
  its 
  growth, 
  and 
  also 
  change 
  form, 
  becoming 
  longer 
  

   in 
  the 
  direction 
  of 
  its 
  length. 
  They 
  are 
  sometimes 
  so 
  numerous 
  as 
  to 
  

   pepper 
  the 
  leaf 
  thickly 
  as 
  if 
  it 
  had 
  been 
  riddled 
  by 
  fine 
  shot, 
  and 
  as 
  they 
  

   increase 
  in 
  size 
  the 
  substance 
  often 
  breaks 
  away 
  between 
  them, 
  making 
  

   large 
  irregular 
  openings. 
  

  

  The 
  numerous 
  species 
  of 
  this 
  family 
  which 
  breed 
  on 
  cultivated 
  

   plants 
  other 
  than 
  beets 
  are 
  not 
  likely 
  to 
  injure 
  beets 
  seriously 
  except 
  in 
  

   the 
  immediate 
  vicinity 
  of 
  such 
  plants. 
  Those 
  which 
  breed 
  on 
  weeds 
  

   are 
  more 
  likely 
  to 
  be 
  injurious, 
  especially 
  in 
  weedy 
  fields. 
  Those 
  which 
  

   breed 
  on 
  the 
  beet 
  leaf 
  itself 
  have 
  rarely 
  been 
  destructively 
  abundant 
  on 
  

   that 
  plant, 
  but 
  are 
  liable 
  to 
  become 
  so 
  at 
  any 
  time. 
  

  

  Since 
  all 
  these 
  insects, 
  in 
  both 
  the 
  adult 
  and 
  larval 
  stages, 
  feed 
  ex- 
  

   posed 
  upon 
  the 
  surface 
  of 
  the 
  leaf, 
  biting 
  and 
  devouring 
  the 
  substance 
  

   of 
  it, 
  they 
  may 
  be 
  destroyed 
  by 
  the 
  ordinary 
  insecticides, 
  especially 
  the 
  

   arsenical 
  sprays. 
  The 
  main 
  difiiculty 
  in 
  the 
  application 
  of 
  these 
  is 
  their 
  

   liability 
  to 
  run 
  off 
  the 
  smooth 
  surface 
  of 
  the 
  leaf, 
  but 
  this 
  may 
  be 
  pre- 
  

   vented 
  in 
  great 
  measure 
  and 
  the 
  efficiency 
  of 
  the 
  insecticide 
  increased 
  

   by 
  a 
  combination 
  with 
  the 
  Bordeaux 
  mixture, 
  as 
  described 
  on 
  another 
  

   page.* 
  Professor 
  Garman, 
  of 
  Kentucky, 
  has 
  found, 
  indeed, 
  that 
  Bor- 
  

   deaux 
  mixture 
  alone 
  is 
  an 
  efficient 
  insecticide 
  for 
  certain 
  of 
  the 
  flea- 
  

   beetles. 
  

  

  The 
  most 
  serious 
  damage 
  by 
  insects 
  of 
  this 
  class 
  is 
  done 
  when 
  the 
  

   beet 
  is 
  very 
  young. 
  Here 
  spraying 
  is 
  obviously 
  futile, 
  since 
  the 
  leaves 
  

   would 
  be 
  eaten 
  before 
  the 
  insects 
  were 
  thoroughly 
  poisoned. 
  This 
  crisis 
  

   may 
  often 
  be 
  avoided, 
  however, 
  by 
  early 
  planting 
  and 
  active 
  cultivation, 
  

   pushing 
  the 
  plant 
  rapidly 
  forward 
  before 
  the 
  attack 
  is 
  fully 
  developed. 
  

  

  *See 
  p. 
  40I. 
  

  

  