﻿8 
  THE 
  DISPERSION" 
  OF 
  THE 
  GIPSY 
  MOTH. 
  

  

  While 
  the 
  gipsy 
  moth 
  does 
  not 
  belong 
  to 
  the 
  same 
  class 
  as 
  the 
  

   scale 
  insects 
  just 
  mentioned, 
  it 
  resembles 
  them 
  inasmuch 
  as 
  it 
  is 
  not 
  

   spread 
  by 
  the 
  flying 
  of 
  the 
  adult, 
  for 
  although 
  the 
  females 
  are 
  pro- 
  

   vided 
  with 
  wings, 
  they 
  are 
  unable 
  to 
  fly, 
  owing 
  to 
  the 
  extreme 
  weight 
  

   of 
  the 
  body. 
  Dispersion, 
  therefore, 
  is 
  greatly 
  restricted 
  in 
  this 
  stage 
  

   of 
  the 
  existence 
  of 
  the 
  insect, 
  and 
  this 
  is 
  important, 
  as 
  it 
  bears 
  directly 
  

   on 
  the 
  control 
  of 
  the 
  species. 
  

  

  INVESTIGATIONS 
  OF 
  THE 
  DISPERSION 
  OF 
  THE 
  GIPSY 
  MOTH. 
  

  

  Investigations 
  which 
  were 
  carried 
  on 
  during 
  the 
  early 
  nineties 
  

   have 
  been 
  fully 
  treated 
  in 
  the 
  report 
  on 
  the 
  gipsy 
  moth 
  by 
  For- 
  

   bush 
  and 
  Fernald, 
  published 
  by 
  the 
  Massachusetts 
  State 
  Board 
  of 
  

   Agriculture 
  in 
  1896, 
  natural 
  and 
  artificial 
  dispersion 
  being 
  con- 
  

   sidered 
  on 
  pages 
  94-116. 
  Although 
  it 
  appeared 
  at 
  that 
  time 
  that 
  

   excellent 
  opportunities 
  were 
  afforded 
  for 
  studying 
  the 
  dispersion 
  of 
  

   this 
  insect, 
  still 
  it 
  must 
  be 
  remembered 
  that 
  the 
  pest 
  was 
  abundant 
  

   in 
  relatively 
  few 
  localities 
  during 
  the 
  years 
  covered 
  by 
  that 
  report, 
  

   especially 
  when 
  the 
  conditions 
  existing 
  in 
  later 
  years 
  are 
  considered 
  

   in 
  comparison. 
  It 
  is 
  evident 
  that 
  the 
  extent 
  of 
  distribution 
  of 
  any 
  

   insect 
  depends 
  largely 
  upon 
  the 
  abundance 
  of 
  the 
  species, 
  and 
  if 
  

   large 
  areas 
  are 
  badly 
  infested 
  migration 
  is 
  often 
  necessary 
  in 
  order 
  

   (hat 
  many 
  of 
  the 
  individuals 
  may 
  secure 
  sufficient 
  food. 
  

  

  The 
  dispersion 
  of 
  the 
  species, 
  as 
  treated 
  in 
  the 
  above 
  mentioned 
  

   report, 
  was 
  considered 
  as 
  local 
  and 
  long 
  distance. 
  The 
  former 
  

   condition 
  was 
  brought 
  about 
  by 
  Qgg 
  clusters 
  being 
  broken 
  and 
  

   scattered 
  by 
  birds 
  or 
  other 
  animals 
  that 
  frequent 
  infested 
  trees. 
  

   Clusters 
  were 
  also 
  carried 
  on 
  driftwood 
  (see 
  PI. 
  I), 
  and 
  those 
  

   deposited 
  on 
  leaves 
  (see 
  PL 
  II) 
  were 
  sometimes 
  distributed 
  by 
  

   the 
  wind. 
  The 
  caterpillars 
  were 
  occasionally 
  found 
  clinging 
  to 
  the 
  

   bodies 
  of 
  animals 
  or 
  to 
  the 
  clothing 
  of 
  persons 
  who 
  had 
  visited 
  

   infested 
  places 
  and 
  were 
  carried 
  short 
  distances 
  in 
  this 
  way. 
  

  

  Many 
  colonies 
  were 
  established 
  in 
  remote 
  districts 
  by 
  the 
  carriage 
  of 
  

   the 
  larva? 
  on 
  vehicles, 
  and 
  egg 
  clusters 
  were 
  sometimes 
  transported 
  

   on 
  cordwood 
  or 
  lumber 
  products 
  shipped 
  from 
  infested 
  forests. 
  (See 
  

   PL 
  III.) 
  The 
  distribution 
  of 
  caterpillars 
  upon 
  vehicles 
  was 
  con- 
  

   sidered 
  so 
  important 
  when 
  the 
  gipsy-moth 
  work 
  was 
  begun 
  in 
  1891 
  

   that 
  inspectors 
  were 
  stationed 
  along 
  the 
  main 
  highways 
  to 
  stop 
  and 
  

   examine 
  all 
  vehicles 
  and 
  to 
  destroy 
  any 
  caterpillars 
  found 
  before 
  

   allowing 
  them 
  to 
  pass 
  out 
  of 
  the 
  infested 
  area. 
  This 
  precaution 
  was 
  

   entirely 
  warranted 
  in 
  view 
  of 
  the 
  discovery 
  that 
  many 
  farms 
  had 
  

   become 
  infested 
  by 
  the 
  transportation 
  of 
  caterpillars 
  on 
  vehicles. 
  

   Places 
  infested 
  in 
  this 
  manner, 
  however, 
  were 
  usually 
  occupied 
  by 
  

   milkmen, 
  peddlers, 
  swill 
  gatherers, 
  or 
  persons 
  whose 
  business 
  caused 
  

   them 
  to 
  drive 
  regularly 
  to 
  and 
  from 
  the 
  city 
  during 
  the 
  summer, 
  or 
  

   to 
  neighborhoods 
  that 
  were 
  badly 
  infested 
  with 
  the 
  gipsy 
  moth. 
  

  

  