﻿the 
  Hessian 
  Fly. 
  349 
  

  

  These 
  and 
  other 
  experiments 
  proved 
  that 
  one 
  male 
  is 
  

   capable 
  of 
  impregnating 
  from 
  one 
  to 
  six 
  females. 
  I 
  have 
  

   noticed 
  females 
  ovipositing 
  at 
  6 
  a.m., 
  and 
  as 
  late 
  as 
  

   7 
  p.m. 
  

  

  Dm-ing 
  July 
  and 
  August 
  I 
  bred 
  a 
  great 
  number 
  of 
  

   females, 
  so 
  determined 
  to 
  see 
  whether 
  they 
  were 
  parthe- 
  

   nogenetic. 
  I 
  placed 
  half-a-dozen 
  of 
  these 
  virgin 
  females 
  

   in 
  separate 
  phials, 
  upon 
  the 
  sides 
  and 
  corks 
  of 
  which 
  all 
  

   oviposited 
  after 
  a 
  few 
  days, 
  but 
  all 
  these 
  dried 
  up 
  in 
  less 
  

   than 
  a 
  week. 
  

  

  On 
  May 
  21st, 
  1889, 
  five 
  virgin 
  flies 
  were 
  "calling," 
  

   and 
  all 
  laid 
  a 
  number 
  of 
  eggs, 
  which 
  I 
  examined 
  most 
  

   carefully 
  under 
  my 
  microscope, 
  but 
  could 
  not 
  see 
  any 
  

   change. 
  I 
  examined 
  them 
  each 
  day 
  until 
  June 
  5th, 
  

   when 
  all 
  were 
  shrivelled 
  up, 
  

  

  I 
  isolated 
  a 
  great 
  many 
  virgin 
  females, 
  but 
  not 
  one 
  of 
  

   the 
  many 
  hundreds 
  of 
  eggs 
  laid 
  ever 
  hatched, 
  so 
  I 
  

   conclude 
  that 
  the 
  Hessian 
  Fly 
  is 
  not 
  parthenogenetic. 
  

   I 
  put 
  four 
  females 
  bred 
  May 
  20th, 
  1889, 
  under 
  a 
  

   cylinder 
  with 
  young 
  barley 
  plants, 
  and 
  they 
  continued 
  to 
  

   "call," 
  keeping 
  the 
  ovipositor 
  slightly 
  in 
  motion 
  and 
  

   fully 
  extended 
  for 
  two 
  or 
  three 
  days, 
  but 
  apparently 
  

   came 
  to 
  the 
  conclusion 
  that 
  there 
  were 
  no 
  partners 
  to 
  be 
  

   had, 
  so 
  they 
  commenced 
  ovipositing, 
  and 
  all 
  died 
  by 
  the 
  

   fifth 
  day. 
  

  

  From 
  the 
  behaviour 
  of 
  the 
  females 
  in 
  captivity, 
  I 
  

   should 
  say 
  that 
  they 
  were 
  very 
  shy 
  in 
  their 
  habits, 
  

   hiding 
  under 
  the 
  leaves 
  and 
  flying 
  but 
  a 
  short 
  distance 
  

   above 
  the 
  ground 
  ; 
  for 
  though 
  I 
  have 
  repeatedly 
  swept 
  

   the 
  stubble 
  and 
  young 
  growing 
  barley, 
  only 
  once 
  (Sept. 
  

   23rd, 
  1887) 
  did 
  I 
  obtain 
  a 
  female. 
  I 
  have 
  frequently 
  

   observed 
  them 
  hide 
  away 
  in 
  holes 
  and 
  crannies 
  in 
  

   the 
  earth, 
  also 
  that 
  they 
  are 
  particularly 
  fond 
  of 
  resting 
  

   there, 
  their 
  colour, 
  I 
  think, 
  protecting 
  them 
  from 
  being 
  

   readily 
  seen 
  by 
  birds. 
  The 
  males 
  fly 
  long 
  distances, 
  as 
  

   proved 
  by 
  those 
  which 
  I 
  captured 
  on 
  the 
  windows 
  of 
  

   Bownham 
  House, 
  Stroud, 
  Sept. 
  22nd, 
  1888, 
  the 
  nearest 
  

   barley 
  or 
  wheat 
  field 
  being 
  about 
  three-quarters 
  of 
  a 
  

   mile 
  away. 
  

  

  My 
  own 
  observations 
  fully 
  confirm 
  all 
  that 
  Prof. 
  C 
  V. 
  

   Eiley 
  and 
  others 
  have 
  stated 
  concerning 
  the 
  weather 
  

   most 
  favourable 
  for 
  the 
  development 
  of 
  the 
  Hessian 
  Fly. 
  

   A 
  warm, 
  damp, 
  *' 
  muggy 
  " 
  atmosphere 
  is 
  decidedly 
  the 
  

   best 
  ; 
  the 
  larvsB 
  thrive 
  quickest 
  in 
  moist 
  and 
  rainy 
  

   weather, 
  and 
  the 
  puparia 
  appear 
  as 
  though 
  they 
  could 
  

  

  