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  in 
  its 
  control, 
  for 
  it 
  breeds 
  at 
  about 
  40° 
  F., 
  while 
  Aphidius 
  

   testaceipes, 
  Cress., 
  its 
  chief 
  parasite, 
  is 
  hardly 
  active 
  below 
  56° 
  F. 
  ; 
  

   consequently 
  mild 
  winters 
  and 
  cool 
  springs 
  allow 
  the 
  aphis 
  to 
  multiply 
  

   unchecked 
  by 
  A. 
  testaceipes. 
  Spring 
  colonies 
  originate 
  either 
  from 
  

   viviparous 
  females, 
  which 
  have 
  wintered 
  on 
  wheat, 
  grasses, 
  etc., 
  or 
  

   from 
  migrants, 
  which 
  are 
  the 
  progeny 
  of 
  sexual 
  forms, 
  from 
  apple 
  

   and 
  related 
  trees. 
  With 
  the 
  approach 
  of 
  winter, 
  the 
  aphids 
  seek 
  the 
  

   lower 
  parts 
  or 
  roots 
  of 
  the 
  wheat 
  or 
  grasses, 
  where 
  the 
  viviparous 
  

   females 
  pass 
  the 
  winter, 
  while 
  the 
  winged 
  forms 
  migrate 
  to 
  apples 
  or 
  

   allied 
  trees. 
  Experiments 
  show, 
  however, 
  that 
  the 
  apple 
  is 
  not 
  

   necessary 
  as 
  an 
  alternative 
  host, 
  especially 
  in 
  the 
  Southern 
  states. 
  

   A. 
  avenae 
  has 
  been 
  reared 
  through 
  more 
  than 
  60 
  consecutive 
  viviparous 
  

   generations, 
  with 
  the 
  aid 
  of 
  a 
  greenhouse 
  in 
  winter. 
  The 
  period 
  from 
  

   birth 
  to 
  maturity 
  varies 
  from 
  6-15 
  days, 
  and 
  four 
  moults 
  occur. 
  

   Other 
  experiments 
  show 
  that 
  this 
  species 
  can 
  survive 
  somewhat 
  

   severe 
  winters 
  as 
  viviparous 
  females. 
  Natural 
  agencies 
  which 
  check 
  

   A. 
  avenae 
  include 
  the 
  following 
  parasites: 
  Pachyneuron 
  micans, 
  

   How., 
  Aphidius 
  testaceipes, 
  Cress., 
  (tritici, 
  Ashm.) 
  ; 
  A. 
  nigriceps, 
  

   Ashm., 
  and 
  the 
  following 
  predaceous 
  insects 
  : 
  Syrphus 
  americanus, 
  

   Wied,, 
  Aphidoletes 
  sp., 
  Hippodamia 
  parenthesis, 
  Say, 
  Coccinella 
  

   9-notata, 
  Herbst, 
  C. 
  6-notata, 
  Kirby, 
  Cycloneda 
  munda. 
  Say, 
  Megilla 
  

   maculata, 
  De 
  G., 
  Scymnus 
  sp., 
  and 
  most 
  important 
  of 
  all, 
  the 
  

   Coccinellid, 
  Hippodamia 
  convergens, 
  Guer. 
  ; 
  many 
  Chrysoptdae 
  are 
  

   also 
  known 
  to 
  feed 
  on 
  A. 
  avenae. 
  Gonatocerus 
  brunneus, 
  Ashm. 
  [M.S.] 
  

   and 
  Polynema 
  longipes, 
  Ashm. 
  (Cosmocena 
  citripes, 
  Ashm.) 
  are 
  also 
  

   believed 
  to 
  prey 
  on 
  it. 
  

  

  Preventive 
  measures 
  recommended 
  include 
  destroying 
  all 
  rank- 
  

   growing 
  wheat 
  near 
  straw-stacks, 
  in 
  early 
  or 
  late 
  autumn 
  ; 
  allowing 
  

   cattle 
  to 
  pasture 
  in 
  wheat 
  and 
  oat-fields 
  in 
  late 
  autumn 
  and 
  early 
  

   winter 
  ; 
  planting 
  wheat 
  as 
  far 
  as 
  possible 
  from 
  the 
  previous 
  year's 
  

   fields, 
  from 
  standing 
  straw-stacks 
  or 
  from 
  apple 
  or 
  other 
  host-plants. 
  

   Where 
  only 
  small 
  areas 
  are 
  badly 
  infested, 
  spray 
  with 
  " 
  black 
  leaf 
  40," 
  

   1 
  part 
  to 
  900 
  parts 
  of 
  water, 
  and 
  1 
  lb. 
  soap 
  to 
  100 
  gallons 
  of 
  spray 
  

   liquid 
  ; 
  where 
  the 
  aphids 
  migrate 
  freely 
  to 
  apple, 
  spray 
  the 
  trees, 
  

   just 
  before 
  the 
  eggs 
  hatch, 
  with 
  commercial 
  lime-sulphur 
  mixture, 
  

   1 
  part 
  to 
  8 
  parts 
  water. 
  

  

  Surface 
  (B. 
  A.). 
  Borers 
  in 
  Hickory 
  Trees. 
  — 
  Zool 
  Press 
  Bull, 
  Penns. 
  

   Dept. 
  Agric., 
  Harrisburg, 
  no. 
  278, 
  24th 
  August 
  1914. 
  

  

  The 
  following 
  note 
  on 
  the 
  sawfly, 
  Tremex 
  columba, 
  is 
  given 
  in 
  answer 
  

   to 
  an 
  inquiry 
  from 
  W. 
  Pennsylvania, 
  where 
  50-60 
  per 
  cent, 
  of 
  Carya 
  

   alba 
  trees 
  have 
  been 
  killed 
  in 
  the 
  last 
  four 
  years 
  by 
  this 
  borer 
  : 
  The 
  

   females 
  lay 
  their 
  eggs 
  beneath 
  the 
  bark 
  of 
  various 
  trees 
  ; 
  their 
  natural 
  

   enemies, 
  which 
  include 
  woodpeckers 
  and 
  Thalessa, 
  are 
  their 
  most 
  

   effective 
  checks 
  ; 
  it 
  is 
  advised, 
  wherever 
  possible, 
  to 
  inject 
  carbon 
  

   bisulphide 
  into 
  the 
  holes 
  and 
  to 
  close 
  these 
  with 
  clay. 
  

  

  ParanaphandScalo. 
  — 
  Agric. 
  News, 
  Barbados, 
  -Km, 
  no. 
  322, 
  29th 
  August 
  

   1914, 
  pp. 
  282-283. 
  

  

  Paranaphisa 
  saturated 
  solution 
  of 
  naphthalin 
  in 
  parafl&n 
  oil, 
  combined 
  

   with 
  soft 
  soap. 
  Combination 
  is 
  easy 
  when 
  the 
  soft 
  soap 
  is 
  boiling 
  and 
  

  

  