﻿112 
  REPORT 
  OF 
  NEW 
  JERSEY 
  STATE 
  MUSEUM. 
  

  

  eggs, 
  from 
  which 
  in 
  spring 
  hatch 
  wingless 
  forms 
  which, 
  in 
  a 
  few 
  days, 
  

   give 
  birth 
  to 
  living 
  young 
  resembling 
  the 
  parents, 
  and, 
  like 
  them, 
  vivip- 
  

   arous, 
  i. 
  e., 
  giving 
  birth 
  to 
  live 
  young, 
  and 
  parthenogenetic, 
  i. 
  e., 
  neither 
  

   male 
  nor 
  female. 
  These 
  young 
  are 
  in 
  tuni 
  ready 
  to 
  reproduce 
  in 
  a 
  few 
  

   days, 
  and 
  give 
  birth 
  to 
  anywhere 
  from 
  4 
  to 
  8 
  daily, 
  according 
  to 
  condi- 
  

   tions. 
  Some 
  time 
  during 
  the 
  early 
  summer 
  winged 
  individuals 
  are 
  pro- 
  

   duced 
  and 
  these 
  fly 
  to 
  other 
  localities 
  or 
  other 
  food-plants, 
  thus 
  spread- 
  

   ing 
  the 
  species. 
  They 
  also 
  are 
  parthenogenetic 
  and 
  usually 
  viviparous, 
  

   and 
  found 
  colonies 
  wherever 
  they 
  alight, 
  the 
  progeny 
  being 
  winged 
  or 
  

   wingless 
  or 
  some 
  of 
  each 
  sort. 
  In 
  the 
  fall, 
  when 
  sap 
  ceases 
  to 
  run 
  and 
  

   ■ 
  food 
  becomes 
  scarce, 
  sexed 
  individuals, 
  male 
  and 
  female, 
  are 
  produced, 
  

   and 
  these 
  copulate, 
  the 
  female 
  laying 
  the 
  winter 
  eggs. 
  There 
  are 
  numer- 
  

   ous 
  modiiications 
  of 
  this 
  life 
  history; 
  but 
  in 
  a 
  general 
  way 
  it 
  applies 
  to 
  a 
  

   large 
  percentage 
  of 
  the 
  species. 
  

  

  Some 
  species 
  have 
  alternate 
  food-plants; 
  i. 
  e., 
  they 
  feed 
  upon 
  one 
  plant 
  

   late 
  in 
  fall 
  and 
  early 
  spring, 
  using 
  it 
  to 
  winter 
  upon, 
  while 
  in 
  summer 
  

   they 
  fly 
  to 
  some 
  annual 
  like 
  the 
  melon 
  or 
  hop 
  that 
  dies 
  down 
  completely 
  

   in 
  fall 
  and 
  renders 
  migration 
  to 
  the 
  winter 
  plants 
  necessary 
  again 
  in 
  late 
  

   summer 
  or 
  fall. 
  The 
  spring 
  migrations 
  usually 
  occur 
  in 
  June 
  and 
  the 
  air 
  

   is 
  then 
  sometimes 
  apparently 
  alive 
  with 
  these 
  minute 
  flying 
  lice. 
  

  

  The 
  rate 
  of 
  increase 
  among 
  these 
  insects 
  is 
  such 
  that, 
  were 
  it 
  not 
  for 
  

   the 
  numerous 
  natural 
  checks, 
  they 
  would 
  soon 
  destroy 
  every 
  particle 
  of 
  

   plant 
  life 
  which 
  they 
  are 
  able 
  to 
  feed 
  upon. 
  

  

  Remedial 
  measures 
  are, 
  winter 
  pruning 
  where 
  eggs 
  are 
  noticed 
  in 
  large 
  

   numbers, 
  the 
  cuttings 
  to 
  be 
  burnt; 
  application 
  of 
  contact 
  insecticides 
  

   early 
  in 
  the 
  season 
  to 
  destroy 
  the 
  stem-mothers; 
  application 
  of 
  contact 
  

   insecticides 
  at 
  any 
  time 
  when 
  the 
  insects 
  are 
  noticed, 
  keeping 
  in 
  mind 
  at 
  

   all 
  times 
  that 
  it 
  is 
  easier 
  to 
  kill 
  a 
  few 
  than 
  to 
  reach 
  a 
  great 
  many, 
  espe- 
  

   cially 
  if 
  they 
  feed 
  so 
  as 
  to 
  distort 
  the 
  leaves 
  or 
  curl 
  them 
  up 
  into 
  shelters 
  

   not 
  easily 
  penetrated 
  by 
  insecticides. 
  Indoors 
  the 
  pyrethrum, 
  dry 
  or 
  in 
  

   the 
  form 
  of 
  decoction, 
  is 
  a 
  favorite 
  and 
  effective 
  remedy. 
  In 
  the 
  field, 
  

   garden 
  or 
  greehouse, 
  tobacco 
  decoction, 
  whale-oil 
  soap 
  or 
  kerosene 
  emul- 
  

   sions 
  are 
  used. 
  Soluble 
  or 
  miscible 
  oils 
  are 
  not 
  safe 
  for 
  summer 
  use 
  at 
  

   effective 
  strengths. 
  Whale-oil 
  soaps 
  are 
  used 
  at 
  from 
  1 
  pound 
  to 
  4 
  to 
  6 
  

   gallons 
  of 
  water, 
  according 
  to 
  the 
  species 
  to 
  be 
  reached. 
  Kerosene 
  emul- 
  

   sion 
  is 
  used 
  diluted 
  with 
  from 
  10 
  to 
  15 
  times 
  its 
  bulk 
  of 
  water, 
  the 
  green 
  

   lice 
  being 
  most 
  easily 
  destroyed 
  in 
  all 
  cases 
  and 
  the 
  black 
  lice 
  the 
  most 
  

   resistant. 
  

  

  Tobacco 
  decoctions, 
  home-made 
  and 
  commercial, 
  are 
  also 
  used, 
  and 
  

   some 
  of 
  the 
  commercial 
  preparations 
  are 
  more 
  effective 
  than 
  the 
  home- 
  

   made 
  mixtures. 
  

  

  Whatever 
  mixtures 
  are 
  used 
  thoroughness 
  in 
  application 
  is 
  always 
  

   essential. 
  All 
  these 
  mentioned 
  are 
  contact 
  poisons 
  and 
  of 
  no 
  effect 
  unless 
  

   actually 
  brought 
  into 
  direct 
  touch 
  with 
  the 
  specimens. 
  Therefore 
  it 
  re- 
  

   quires 
  not 
  only 
  a 
  proper 
  nozzle 
  to 
  make 
  a 
  fine 
  spray, 
  but 
  also 
  a 
  sufficient 
  

   amount 
  of 
  force 
  to 
  drive 
  this 
  spray 
  to 
  the 
  specimens. 
  

  

  Under 
  some 
  circumstances 
  even 
  cold 
  water 
  will 
  kill 
  plant 
  lice, 
  and 
  a 
  

   cold 
  storm 
  in 
  middle 
  or 
  late 
  June 
  will 
  play 
  havoc 
  with 
  the 
  migrating 
  

  

  