﻿WAGNER 
  ON 
  THE 
  HESSIAN 
  FLY. 
  

  

  [9} 
  

  

  of 
  mosquito 
  netting 
  on 
  garden-soil 
  mixed 
  with 
  much 
  sand, 
  which 
  was 
  

   kept 
  moist 
  from 
  below. 
  These 
  net-cages 
  were 
  exposed 
  to 
  every 
  change 
  

   of 
  the 
  weather, 
  thus 
  imitating 
  the 
  conditions 
  of 
  those 
  not 
  in 
  captivity. 
  

   During 
  the 
  whole 
  time 
  of 
  observation 
  my 
  attention 
  was 
  also 
  drawn 
  ta 
  

   the 
  metamorphoses 
  going 
  on 
  in 
  the 
  insect 
  in 
  a 
  state 
  of 
  nature. 
  By 
  com- 
  

   paring 
  the 
  latter 
  with 
  those 
  in 
  formation 
  in 
  the 
  nets 
  I 
  believed 
  that 
  the 
  

   observations 
  were 
  without 
  those 
  mistakes 
  which 
  even 
  the 
  best 
  con- 
  

   structed, 
  but 
  sometimes 
  partially 
  manipulated, 
  net-cages 
  can 
  never 
  

   fully 
  escape. 
  However 
  much 
  certain 
  objections 
  may 
  be 
  made 
  to 
  rais- 
  

   ing 
  them 
  in 
  captivity, 
  yet, 
  properly 
  conducted, 
  especially 
  when 
  kept 
  under 
  

   continued 
  control 
  with 
  the 
  metamori^hoses 
  going 
  on 
  outside, 
  Its 
  impor- 
  

   tance 
  is 
  not 
  to 
  be 
  contested 
  ; 
  this 
  medium 
  for 
  the 
  determination 
  of 
  the 
  

   swarming 
  time 
  could 
  not 
  have 
  been 
  omitted 
  in 
  the 
  present 
  case. 
  From 
  

   the 
  compilation 
  of 
  the 
  collected 
  notes 
  on 
  the 
  hatched 
  flies 
  has 
  resulted 
  

   the 
  following 
  table. 
  I 
  have 
  to 
  add 
  the 
  remark 
  that 
  the 
  number 
  of 
  flies 
  

   obtained 
  from 
  the 
  various 
  kinds 
  of 
  crops 
  does 
  not 
  in 
  the 
  least 
  represent 
  a 
  

   measure 
  of 
  the 
  more 
  or 
  less 
  frequency 
  of 
  the 
  insect 
  in 
  the 
  respective 
  

   graminaceous 
  genera. 
  For 
  the 
  least 
  would 
  such 
  an 
  inference 
  be 
  made 
  

   regarding 
  barley. 
  That 
  I 
  obtained 
  comparatively 
  many 
  flies 
  from 
  it 
  is 
  

   to 
  be 
  explained 
  by 
  the 
  fact 
  that 
  the 
  collection 
  of 
  pupae 
  was 
  locally 
  more 
  

   convenient 
  for 
  me. 
  Winter 
  rye 
  yielded 
  few 
  flies, 
  on 
  account 
  of 
  the 
  

   greater 
  distance 
  of 
  the 
  localities 
  where 
  pupae 
  would 
  have 
  occurred 
  in 
  

   quantities. 
  

  

  Kind 
  of 
  crop. 
  

  

  1 
  

  

  o 
  

  

  1 
  

  

  Sex. 
  

  

  N"umber 
  of 
  an- 
  

   tennal 
  joints. 
  

  

  ® 
  

  

  II 
  

  

  •Si 
  

  

  a 
  

   pi 
  

  

  m 
  

  

  Winter 
  wheat 
  ■,... 
  

  

  28 
  

  

  29 
  

  

  30 
  

  

  Sept. 
  1 
  

  

  2 
  

  

  4 
  

  

  7 
  

  

  13 
  

  

  18 
  

  

  21 
  

  

  24 
  

  

  29 
  

  

  30 
  

  

  Oct. 
  2 
  

  

  5 
  

  

  .... 
  

   '^' 
  

  

  "cf" 
  

   "d' 
  

  

  "<s' 
  

  

  d 
  

  

  ? 
  

  

  'i4 
  

  

  15 
  

   15 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  16 
  

  

  

  

  

  

  I 
  

  

  '14' 
  

  

  15 
  

   15 
  

   15 
  

  

  .... 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  16 
  

   16 
  

   16 
  

  

  .... 
  

  

  1:2 
  

  

  18 
  

  

  

  ? 
  

  

  

  

  

  

  

  - 
  

  

  

  

  

  

  1 
  

  

  

  15 
  

  

  

  

  

  

  16 
  

  

  

  

  

  

  

  

  17 
  

  

  

  

  

  ? 
  

  

  ::: 
  

  

  15 
  

   15 
  

  

  'is' 
  

  

  

  

  

  

  

  

  

  

  

  16 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  Winter 
  rve 
  

  

  Sept. 
  7 
  

  

  9 
  

  

  26 
  

  

  27 
  

  

  "d 
  

  

  ? 
  

  

  .... 
  

  

  15 
  

  

  

  

  

  

  

  16 
  

  

  

  

  

  

  5 
  

   ? 
  

  

  .... 
  

  

  15 
  

   15 
  

  

  

  1:3 
  

  

  4. 
  

  

  ••• 
  ' 
  

  

  

  

  

  

  

  

  

  

  Summer 
  rye 
  

  

  Sept. 
  8 
  

   15 
  

  

  "d 
  

  

  9 
  

  

  — 
  

  

  15 
  

  

  

  

  

  

  

  16 
  

  

  .... 
  

  

  "ili" 
  

  

  2' 
  

  

  

  

  

  

  

  Summ 
  er 
  barley 
  

  

  Aug. 
  31 
  

  

  Sept. 
  3 
  

  

  4 
  

  

  6 
  

  

  15 
  

  

  26 
  

  

  28 
  

  

  28 
  

  

  Oct. 
  4 
  

  

  "d 
  

  

  "d 
  

   d 
  

  

  "d' 
  

   12 
  

  

  ? 
  

  

  

  15 
  

  

  

  

  

  

  

  16 
  

  

  

  

  

  

  1 
  

  

  14 
  

  

  14 
  

  

  

  

  

  

  

  15 
  

   15 
  

  

  

  

  

  

  

  

  

  4:5 
  

  

  9' 
  

  

  

  

  

  16 
  

  

  

  

  « 
  

  

  1 
  

  

  .... 
  

  

  15 
  

   15 
  

  

  

  

  

  

  

  

  

  

  

  16 
  

   11 
  

  

  

  

  

  

  21 
  

  

  3 
  

  

  18 
  

  

  

  ...... 
  

  

  

  Altcether 
  

  

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