﻿384 
  

  

  has 
  hatched, 
  and 
  the 
  time 
  between 
  oviposition 
  and 
  the 
  time 
  the 
  young 
  

   larva 
  was 
  first 
  seen 
  varied 
  from 
  two 
  days 
  to 
  about 
  a 
  week. 
  The 
  

   length 
  of 
  the 
  larval 
  stage 
  varies 
  with 
  climatic 
  conditions, 
  in 
  summer 
  

   being 
  5-7 
  days, 
  in 
  cooler 
  weather 
  10-12 
  days. 
  The 
  emergence 
  of 
  the 
  

   imago 
  occurs 
  at 
  night 
  in 
  warm 
  weather, 
  and 
  in 
  cooler 
  weather 
  during 
  

   the 
  day. 
  

  

  In 
  a 
  number 
  of 
  experiments 
  conducted 
  to 
  determine 
  the 
  relation 
  

   and 
  economy 
  of 
  the 
  sexes, 
  it 
  was 
  found 
  that 
  where 
  a 
  male 
  was 
  suppUed 
  

   to 
  each 
  female 
  a 
  higher 
  percentage 
  of 
  parasitism 
  was 
  obtained, 
  and 
  

   a 
  greater 
  number 
  of 
  parasites 
  reached 
  maturity. 
  It 
  was 
  not 
  possible 
  

   to 
  determine 
  with 
  any 
  degree 
  of 
  accuracy 
  the 
  number 
  of 
  eggs 
  a 
  female 
  

   could 
  deposit. 
  Nineteen 
  individuals 
  parasitised 
  an 
  average 
  of 
  6*2 
  

   eggs 
  ; 
  76 
  of 
  the 
  first 
  generation 
  parasitised 
  an 
  average 
  of 
  4*1 
  eggs 
  ; 
  

   63 
  of 
  the 
  second 
  generation 
  parasitised 
  an 
  average 
  of 
  3*7 
  eggs 
  ; 
  31 
  

   of 
  the 
  third 
  generation 
  parasitised 
  an 
  average 
  of 
  3*7 
  eggs. 
  The 
  largest 
  

   number 
  of 
  eggs 
  parasitised 
  by 
  a 
  single 
  female 
  was 
  13. 
  In 
  females, 
  

   before 
  oviposition, 
  the 
  smallest 
  number 
  of 
  eggs 
  in 
  the 
  ovary 
  was 
  13, 
  

   the 
  largest 
  29. 
  The 
  number 
  of 
  females 
  greatly 
  exceeds 
  the 
  number 
  of 
  

   males, 
  both 
  in 
  the 
  field 
  and 
  in 
  the 
  laboratory. 
  The 
  insect 
  can 
  breed 
  

   parthenogenetically, 
  but 
  the 
  number 
  of 
  eggs 
  parasitised 
  per 
  female 
  

   was 
  usually 
  low, 
  and 
  many 
  of 
  the 
  offspring 
  failed 
  to 
  develop. 
  

  

  The 
  short 
  existence 
  of 
  the 
  adult 
  is 
  directed 
  almost 
  entirely 
  towards 
  

   reproduction 
  ; 
  feeding, 
  if 
  any, 
  requires 
  a 
  very 
  short 
  time. 
  In 
  the 
  

   wheat 
  fields 
  the 
  parasites 
  were 
  always 
  moving 
  about 
  on 
  the 
  plants 
  

   near 
  and 
  below 
  the 
  surface 
  of 
  the 
  ground 
  and, 
  unless 
  disturbed, 
  seldom 
  

   take 
  to 
  wing. 
  Although 
  it 
  would 
  seem 
  that 
  they 
  spend 
  their 
  hves 
  in 
  

   comparatively 
  Hmited 
  areas, 
  they 
  range 
  to 
  a 
  greater 
  extent 
  than 
  might 
  

   be 
  expected 
  ; 
  the 
  wind 
  probably 
  helps 
  in 
  their 
  distribution. 
  In 
  all 
  

   experiments 
  in 
  which 
  hosts 
  other 
  than 
  the 
  chinch 
  bugs 
  were 
  offered 
  

   to 
  the 
  Chalcids, 
  parasitism 
  did 
  not 
  occur. 
  

  

  The 
  length 
  of 
  the 
  life 
  of 
  the 
  parasite 
  varies 
  greatly 
  with 
  factors 
  such 
  

   as 
  food, 
  temperature, 
  etc. 
  ; 
  it 
  has 
  been 
  found 
  to 
  range 
  from 
  a 
  few 
  

   hours 
  to 
  twenty-five 
  days. 
  The 
  first 
  parasitised 
  chinch 
  bug 
  eggs 
  were 
  

   found 
  at 
  the 
  end 
  of 
  April, 
  so 
  that 
  the 
  parasites 
  must 
  have 
  been 
  out 
  

   before 
  this 
  date. 
  There 
  are 
  about 
  nine 
  or 
  ten 
  generations 
  ; 
  the 
  last 
  

   parasite 
  was 
  observed 
  in 
  the 
  middle 
  of 
  October. 
  

  

  The 
  parasite 
  was 
  first 
  discovered 
  in 
  a 
  wheat 
  field 
  near 
  Manhattan. 
  

   Since 
  then 
  it 
  has 
  been 
  found 
  throughout 
  the 
  whole 
  State, 
  wherever 
  

   chinch 
  bug 
  infestations 
  occur. 
  The 
  eggs 
  of 
  one 
  brood 
  of 
  the 
  chinch 
  

   bug 
  are 
  exposed 
  to 
  the 
  attack 
  of 
  four 
  or 
  five 
  broods 
  of 
  the 
  parasite 
  ; 
  

   at 
  least 
  50 
  per 
  cent, 
  of 
  any 
  one 
  brood 
  of 
  chinch 
  bugs 
  appear 
  to 
  be 
  

   parasitised. 
  

  

  HoDGKiss 
  (H. 
  E.) 
  & 
  Pabrott 
  (p. 
  J.). 
  The 
  Parasites 
  of 
  the 
  San 
  Jos6 
  

   Scale 
  in 
  New 
  York. 
  — 
  Jl. 
  Econ. 
  Entom., 
  Concord, 
  vii, 
  no. 
  2, 
  April' 
  

   1914, 
  pp. 
  227-229. 
  

  

  Parasites 
  of 
  the 
  San 
  Jose 
  scale 
  {Aspidiotus 
  perniciosus) 
  were 
  numerous 
  

   during 
  1913 
  in 
  New 
  York. 
  To 
  determine 
  the 
  range 
  and 
  species 
  of 
  

   these 
  insects, 
  infested 
  wood 
  was 
  collected 
  from 
  unsprayed 
  trees 
  in 
  the 
  

   more 
  important 
  fruit-growing 
  districts 
  of 
  the 
  State. 
  From 
  the 
  

   material 
  the 
  authors 
  reared 
  the 
  following 
  species 
  : 
  — 
  Pwspaltella 
  

   jperniciosi, 
  Tower, 
  Aphelinus 
  fuscipennis, 
  Howard, 
  A. 
  diaspidis,. 
  

  

  