﻿APPE]\I>IX 
  II. 
  

  

  A. 
  

   DESOEIPTIO^ 
  OF 
  THE 
  EYE 
  GALL-GNAT. 
  

  

  BY 
  DR. 
  HERMANN 
  LOEW. 
  

  

  Extracted 
  from 
  *' 
  Die 
  neue 
  Komraade 
  und 
  die 
  Mattel, 
  -welclie 
  gegen 
  sie 
  anzuwenden 
  sind." 
  Von 
  Dr. 
  

  

  H. 
  Loew.* 
  1859. 
  

  

  VARIOUS 
  VIEWS 
  AS 
  TO 
  THE 
  ORIGINAL 
  NATIVE 
  COUNTRY 
  OF 
  THE 
  

  

  HESSIAN 
  PLY. 
  

  

  The 
  Hessian 
  fly 
  became 
  first 
  known 
  in 
  America, 
  in 
  1779, 
  by 
  the 
  great 
  

   devastation 
  done 
  to 
  wheat 
  on 
  Staten 
  Island 
  and 
  the 
  west 
  end 
  of 
  Long 
  

   Island, 
  and, 
  on 
  account 
  of 
  the 
  yearly 
  increasing 
  rapidity 
  of 
  damage, 
  

   spreading 
  over 
  large 
  tracts 
  of 
  laud, 
  was 
  soon 
  greatly 
  feared, 
  the 
  damage 
  

   done 
  in 
  some 
  cases 
  being 
  from 
  one-fifth 
  to 
  three-fourths 
  of 
  the 
  entire 
  har- 
  

   vest. 
  The 
  idea 
  that 
  the 
  Hessian 
  fly 
  was 
  introduced 
  with 
  packing-straw 
  

   by 
  Hessian 
  troops 
  who 
  landed 
  on 
  Long 
  Island 
  in 
  August, 
  1776, 
  soon 
  

   became 
  prevalent. 
  Later, 
  doubts 
  arose. 
  Some 
  were 
  disposed 
  to 
  believe 
  

   that 
  it 
  was 
  an 
  American 
  species, 
  and 
  that 
  its 
  immense 
  multiplication 
  was 
  

   only 
  a 
  consequence 
  of 
  the 
  rapidly 
  spreading 
  culture 
  of 
  wheat 
  j 
  some 
  were 
  

   convinced 
  that 
  the 
  fly 
  did 
  not 
  occur 
  at 
  all 
  in 
  Europe. 
  After 
  the 
  latter 
  

   idea 
  had 
  been 
  generally 
  current 
  for 
  a 
  long 
  series 
  of 
  years, 
  and 
  the 
  same 
  

   was 
  acknowledged 
  as 
  a 
  fact 
  even 
  by 
  scientific 
  institutes, 
  a 
  Cecidomyia 
  

   was 
  observed 
  by 
  Herrickf 
  on 
  Minorca, 
  by 
  Dana 
  near 
  Toulon 
  and 
  I^aples, 
  

   and 
  by 
  myself 
  on 
  the 
  coast 
  of 
  Asia 
  Minor, 
  which 
  fly 
  attacks 
  the 
  wheat 
  

   in 
  the 
  same 
  manner 
  as 
  Cecidomyia 
  destructor 
  in 
  America, 
  and 
  whose 
  larva 
  

   likewise 
  transforms 
  into 
  a 
  ^' 
  pupa 
  obtecta." 
  Upon 
  these 
  facts 
  the 
  idea 
  

   of 
  the 
  occurrence 
  of 
  the 
  fly 
  in 
  Europe 
  again 
  gained 
  ground, 
  and 
  it 
  seems 
  

   as 
  if 
  the 
  investigators 
  completed 
  the 
  cycle 
  by 
  definitely 
  regarding 
  it 
  as 
  

   indigenous 
  to 
  Europe, 
  and 
  declared 
  it, 
  as 
  in 
  the 
  beginning, 
  as 
  only 
  in- 
  

   troduced. 
  Fitch 
  in 
  his 
  paper 
  strongly 
  holds 
  to 
  this. 
  He 
  partly 
  relies 
  

   on 
  the 
  authority 
  of 
  Herrick, 
  who, 
  before 
  he 
  made 
  himself 
  acquainted 
  

   with 
  the 
  species 
  from 
  southern 
  Europe, 
  observed 
  the 
  genuine 
  Cecidomyia 
  

   destructor 
  in 
  America, 
  and 
  regarded 
  them 
  both 
  as 
  identical. 
  Fitch 
  also 
  

   partly 
  forms 
  this 
  theory 
  from 
  a 
  glance 
  at 
  some 
  specimens 
  of 
  a 
  European 
  

   species 
  sent 
  to 
  him 
  by 
  Herrick, 
  but 
  so 
  extremely 
  briefly 
  does 
  he 
  report 
  

   on 
  this 
  comparison 
  that 
  I 
  cannot 
  consent 
  to 
  the 
  i)roof 
  of 
  identity 
  of 
  

   both 
  species. 
  Eegarding 
  the 
  question 
  whether 
  the 
  species 
  from 
  south- 
  

   ern 
  Europe 
  be 
  identical 
  with 
  our 
  rye 
  gall-gnat, 
  I 
  must 
  desist 
  at 
  present, 
  

   as 
  I 
  neither 
  possess 
  specimens 
  of 
  the 
  former 
  nor 
  a 
  complete 
  description, 
  

   and 
  my 
  reminiscences 
  of 
  the 
  larvse 
  and 
  pupae 
  observed 
  almost 
  sixteen 
  

   years 
  ago 
  have 
  by 
  the 
  course 
  of 
  time 
  becameo'ather 
  indistinct. 
  

  

  WHETHER 
  THE 
  RYE 
  AND 
  THE 
  HESSIAN 
  FLY 
  ARE 
  ONE 
  AND 
  THE 
  SAME 
  

  

  SPECIES. 
  

  

  Whoever 
  specially 
  studies 
  the 
  natural 
  history 
  of 
  the 
  gall-gnats 
  knows 
  

   that 
  the 
  closely 
  allied 
  species 
  of 
  this 
  genus 
  in 
  the 
  complete 
  state 
  differ 
  

   at 
  most 
  only 
  by 
  very 
  delicate 
  characters, 
  easily 
  escaping 
  notice, 
  and 
  that 
  

   in 
  the 
  earlier 
  stages 
  they 
  agree 
  still 
  more 
  among 
  themselves, 
  so 
  that 
  

   the 
  effects 
  on 
  the 
  cereal 
  which 
  they 
  infest, 
  and 
  the 
  structure 
  of 
  the 
  

  

  * 
  Translated 
  by 
  Dr. 
  C. 
  F. 
  Gissler. 
  

  

  t 
  This 
  is 
  a 
  mistake. 
  Prof. 
  J. 
  D. 
  Dana 
  foand 
  tlie 
  larvse 
  and 
  pupae, 
  and 
  reared 
  the 
  flies 
  from 
  wheat 
  

   growing 
  on 
  the 
  island 
  of 
  Minorca. 
  — 
  A. 
  S. 
  P. 
  

  

  [6] 
  

  

  