﻿HABITS. 
  13 
  

  

  carefully 
  removed 
  from 
  each 
  leaf. 
  When 
  mature 
  the 
  two 
  females 
  

  

  that 
  survived 
  upon 
  the 
  isolated 
  leaves 
  were 
  carefully 
  watched 
  to 
  

  

  be 
  sure 
  that 
  no 
  male 
  mite 
  reached 
  them. 
  Thirty-three 
  eggs 
  were 
  

  

  deposited 
  by 
  these 
  virgin 
  mites 
  and 
  all 
  of 
  the 
  26 
  that 
  hatched 
  were 
  

  

  males. 
  

  

  HABITS. 
  

  

  HABITATION. 
  

  

  Small 
  numbers 
  of 
  mites 
  were 
  observed 
  during 
  the 
  early 
  summer 
  on 
  

   the 
  underside 
  of 
  hop 
  leaves. 
  A 
  few 
  strands 
  of 
  web 
  were 
  usually 
  pres- 
  

   ent 
  to 
  begin 
  with, 
  and 
  as 
  the 
  number 
  of 
  mites 
  increased 
  the 
  web 
  

   became 
  more 
  extensive 
  and 
  was 
  observed 
  frequently 
  to 
  cover, 
  in 
  an 
  

   irregular 
  manner, 
  the 
  entire 
  underside 
  of 
  the 
  infested 
  foliage. 
  The 
  

   lower 
  leaves 
  were 
  first 
  attacked, 
  but 
  as 
  infestation 
  increased 
  these 
  

   leaves, 
  which 
  were 
  severely 
  injured, 
  began 
  to 
  dry 
  and 
  thus 
  forced 
  an 
  

   upward 
  migration 
  of 
  the 
  mites. 
  By 
  August 
  the 
  entire 
  vines 
  were 
  

   infested 
  and 
  in 
  severe 
  cases 
  mites 
  were 
  observed 
  upon 
  the 
  surface 
  

   as 
  well 
  as 
  the 
  underside 
  of 
  the 
  leaves. 
  

  

  PROTECTION. 
  

  

  Inhabiting 
  as 
  they 
  do 
  the 
  underside 
  of 
  the 
  leaves, 
  the 
  mites 
  are 
  

   well 
  protected 
  from 
  wind 
  and 
  other 
  climatic 
  conditions. 
  Further 
  

   than 
  this, 
  the 
  web 
  which 
  is 
  spun 
  indiscriminately 
  across 
  the 
  under- 
  

   side 
  of 
  the 
  infested 
  foliage 
  affords 
  the 
  mites 
  much 
  protection. 
  Where 
  

   the 
  finer 
  mist 
  sprays 
  were 
  used 
  the 
  webs 
  were 
  frequently 
  not 
  pene- 
  

   trated 
  and 
  the 
  mites 
  beneath 
  remained 
  uninjured. 
  This 
  combina- 
  

   tion 
  of 
  web 
  and 
  leaf 
  affords 
  the 
  mites 
  great 
  freedom 
  from 
  injury. 
  The 
  

   web 
  of 
  the 
  red 
  spider 
  is 
  spun 
  by 
  either 
  sex, 
  and 
  is 
  at 
  all 
  times 
  carried 
  

   about 
  by 
  the 
  mite 
  as 
  a 
  guard 
  against 
  falling. 
  It 
  thus 
  becomes 
  scat- 
  

   tered 
  over 
  the 
  underside 
  of 
  infested 
  leaves 
  and 
  other 
  objects 
  over 
  

   which 
  the 
  mites 
  may 
  crawl. 
  

  

  HIBERNATION. 
  

  

  A 
  careful 
  examination, 
  during 
  February 
  and 
  March, 
  1911, 
  of 
  soil 
  

   and 
  hop 
  roots 
  taken 
  from 
  fields 
  which 
  were 
  badly 
  injured 
  by 
  the 
  red 
  

   spider 
  in 
  1910 
  failed 
  to 
  reveal 
  any 
  hibernating 
  mites 
  or 
  overwintering 
  

   eggs. 
  During 
  1911 
  the 
  mites 
  were 
  found 
  only 
  upon 
  violets 
  and 
  mal- 
  

   low 
  ( 
  Malva 
  parviflora) 
  which 
  grew 
  in 
  a 
  flower 
  garden 
  half 
  a 
  mile 
  from 
  

   the 
  hopyards, 
  but 
  they 
  were 
  observed 
  in 
  considerable 
  numbers 
  the 
  

   following 
  fall, 
  winter, 
  and 
  spring 
  upon 
  wild 
  morning-glory 
  and 
  mallow 
  

   in 
  all 
  parts 
  of 
  the 
  hopyards. 
  

  

  It 
  is 
  evident, 
  therefore, 
  that 
  the 
  mites 
  pass 
  the 
  winter 
  upon 
  wild 
  

   plants 
  in 
  and 
  around 
  the 
  hopyards, 
  as 
  has 
  been 
  found 
  true 
  of 
  the 
  red 
  

   spider 
  attacking 
  cotton 
  in 
  the 
  Southern 
  States, 
  by 
  Mr. 
  E. 
  A. 
  McGregor 
  

   of 
  this 
  bureau. 
  

  

  