﻿26 
  

  

  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Flight 
  and 
  dissemination. 
  This 
  is 
  something 
  of 
  great 
  import- 
  

   ance 
  in 
  view 
  of 
  the 
  part 
  flies 
  may 
  play 
  in 
  the 
  spread 
  of 
  disease. 
  The 
  

   experiments 
  of 
  Dr 
  L. 
  O. 
  Howard, 
  Government 
  Entomologist, 
  have 
  

   shown 
  conclusively 
  that 
  the 
  major 
  portion 
  of 
  the 
  flics 
  about 
  a 
  

   building 
  breed 
  in 
  the 
  immediate 
  vicinity, 
  probably 
  within 
  300 
  to 
  

   500 
  feet. 
  There 
  is 
  no 
  denying 
  the 
  fact 
  that 
  this 
  insect 
  is 
  capable 
  

   of 
  flying 
  considerable 
  distances 
  but 
  ordinarily 
  this 
  does 
  not 
  seem 
  

   to 
  occur. 
  There 
  is 
  another 
  phase 
  of 
  this 
  question 
  which 
  has 
  ap- 
  

   parently 
  received 
  little 
  consideration, 
  namely, 
  the 
  conveyance 
  of 
  

   flies 
  by 
  vehicles 
  of 
  one 
  kind 
  or 
  another. 
  Only 
  a 
  little 
  observation 
  

   is 
  necessary 
  to 
  show 
  that 
  the 
  butcher 
  cart 
  of 
  the 
  country 
  is 
  a 
  very 
  

   efficient 
  carrier 
  of 
  flies, 
  presumably 
  receiving 
  accessions 
  and 
  leav- 
  

   ing 
  individuals 
  at 
  almost 
  every 
  stopping 
  place, 
  even 
  though 
  the 
  

   route 
  traversed 
  may 
  occupy 
  an 
  entire 
  day. 
  The 
  same 
  is 
  true, 
  

   though 
  to 
  a 
  more 
  limited 
  extent, 
  of 
  trolley 
  cars 
  and 
  express 
  cars 
  

  

  carrying 
  sacked 
  meat 
  or 
  other 
  supplies 
  

   equally 
  attractive 
  to 
  flies. 
  It 
  is 
  onl^ 
  

   necessary 
  for 
  these 
  carriers 
  to 
  load 
  

   where 
  conditions 
  are 
  favorable 
  for 
  the 
  

   infection 
  of 
  flies 
  and 
  we 
  may 
  have 
  a 
  

   mysterious 
  outbreak 
  of 
  disease 
  at 
  some 
  

   distance 
  from 
  the 
  source 
  of 
  trouble. 
  

  

  Natural 
  enemies. 
  The 
  house 
  fly, 
  

   though 
  so 
  abundant, 
  is 
  subject 
  to 
  attack 
  

   by 
  various 
  natural 
  enemies. 
  One 
  of 
  the 
  

   most 
  common 
  is 
  a 
  fungous 
  disease 
  

   known 
  as 
  Empusa 
  muscae 
  which 
  

   is 
  occasionally 
  responsible 
  .for 
  the 
  death 
  

   of 
  many 
  flies, 
  particularly 
  toward 
  the 
  

   end 
  of 
  the 
  summer. 
  It 
  is 
  not 
  uncom- 
  

   mon 
  to 
  find 
  a 
  few 
  individuals 
  affected 
  

   by 
  this 
  disease 
  every 
  year. 
  A 
  small, 
  

   reddish 
  mite 
  may 
  be 
  occasionally 
  found 
  

   attached 
  to 
  flies, 
  seriously 
  weakening 
  

   the 
  host. 
  There 
  are, 
  in 
  addition, 
  wasps 
  

   and 
  spiders 
  which 
  prey 
  upon' 
  flies 
  and 
  

   undoubtedly 
  are 
  of 
  considerable 
  service 
  

   s|en 
  though 
  they 
  are 
  very 
  rarely 
  sufficiently 
  

   still 
  more 
  enlarged." 
  (After 
  Wood) 
  abuudaut 
  to 
  materially 
  rcducc 
  the 
  num- 
  

   bers 
  of 
  this 
  pest. 
  Another 
  interesting 
  enemy 
  of 
  the 
  house 
  fly 
  

   is 
  known 
  as 
  the 
  house 
  centipede, 
  Scutigera 
  forceps 
  Raf., 
  

  

  Fig 
  

  

  House 
  centipede; 
  

  

  from 
  above, 
  enlarged, 
  the 
  head 
  

  

  