﻿THE 
  SPRING 
  CANKER 
  WORM: 
  ITS 
  RANGE. 
  171 
  

  

  there. 
  We 
  have 
  specimeus 
  obtaiued 
  by 
  the 
  late 
  Jacob 
  Boll 
  near 
  Dallas, 
  

   Tex., 
  which 
  is 
  the 
  southernmost 
  reliable 
  limit 
  in 
  the 
  West, 
  while 
  its 
  

   northernmost 
  recorded 
  limit, 
  west 
  of 
  Lake 
  Michigan, 
  is 
  in 
  Eock 
  County, 
  

   Wis. 
  In 
  Michigan 
  it 
  had 
  in 
  1870 
  nearly 
  reached 
  the 
  northern 
  extremity 
  

   of 
  the 
  southern 
  peninsula. 
  It 
  does 
  not 
  seem 
  to 
  trouble 
  the 
  orchardists 
  

   in 
  the 
  Atlantic 
  States 
  south 
  of 
  New 
  Jersey, 
  since 
  it 
  is 
  not 
  reported 
  there- 
  

   from. 
  Dr. 
  Packard 
  says:^"^ 
  "It 
  is 
  probable 
  that 
  it 
  is 
  indigenous 
  to 
  all 
  

   parts 
  of 
  the 
  country 
  east 
  of 
  the 
  Mississippi, 
  but 
  is 
  abundant 
  only 
  locally 
  

   originally 
  along 
  the 
  coast 
  of 
  northeastern 
  Massachusetts, 
  and 
  of 
  late 
  

   years 
  in 
  Illinois 
  and 
  Missouri 
  '^j 
  but 
  the 
  evidence 
  seems 
  to 
  show 
  a 
  pro- 
  

   gressive 
  dispersion 
  of 
  the 
  insect 
  westward, 
  doubtless 
  by 
  man^s 
  aid. 
  

  

  As 
  might 
  be 
  expected 
  from 
  the 
  wingless 
  character 
  of 
  the 
  females, 
  

   their 
  distribution 
  is 
  very 
  unequal, 
  and 
  apparently 
  arbitrary, 
  a 
  common 
  

   road 
  sometimes 
  serving 
  for 
  years 
  as 
  a 
  barrier 
  between 
  a 
  free 
  and 
  an 
  in- 
  

   fested 
  orchard. 
  The 
  evidence 
  is 
  conclusive 
  as 
  to 
  the 
  common 
  occur- 
  

   rence 
  of 
  this 
  particular 
  species 
  in 
  Maine, 
  Massachusetts, 
  New 
  York, 
  

   Pennsylvania, 
  Michigan, 
  Wisconsin, 
  Illinois, 
  Iowa, 
  Missouri, 
  and 
  Texas, 
  

   but 
  it 
  is 
  not 
  so 
  certain 
  as 
  to 
  which 
  of 
  the 
  two 
  species 
  the 
  accounts 
  from 
  

   Canada, 
  New 
  Hampshire, 
  Vermont, 
  Ehode 
  Island, 
  Connecticut, 
  New 
  

   Jersey, 
  Ohio, 
  and 
  Indiana 
  refer 
  to, 
  though 
  vernata 
  in 
  ipany 
  instances 
  

   is 
  presumably 
  the 
  kind. 
  

  

  CHARACTERS. 
  

  

  Imago. 
  — 
  The 
  Spring 
  Canker 
  Worm 
  is 
  distinguished 
  in 
  the 
  perfect 
  state 
  

   by 
  the 
  iirst 
  seven 
  joints 
  of 
  the 
  abdomen 
  bearing 
  each 
  two 
  transverse 
  

   rows 
  of 
  stiff 
  reddish 
  spines, 
  pointing 
  posteriorly, 
  more 
  prominent 
  in 
  the 
  

   female 
  than 
  in 
  the 
  male, 
  and 
  often 
  giving 
  the 
  abdomen 
  a 
  reddish 
  ap- 
  

   pearance. 
  It 
  is 
  rather 
  smaller 
  in 
  size 
  than 
  the 
  Fall 
  species, 
  the 
  male 
  

   measuring 
  from 
  tip 
  to 
  tip 
  of 
  wings 
  when 
  expanded 
  from 
  about 
  five-sixths 
  

   of 
  an 
  inch 
  [21™™] 
  to 
  over 
  an 
  inch 
  and 
  a 
  quarter 
  [32™™], 
  and 
  the 
  female 
  

   from 
  a 
  fifth 
  to 
  a 
  little 
  over 
  a 
  third 
  of 
  an 
  inch 
  [S-O*"™] 
  in 
  length. 
  

  

  Male. 
  — 
  The 
  wings 
  of 
  the 
  male 
  are 
  silky 
  and 
  delicate, 
  the 
  front 
  ones 
  

   marked 
  with 
  three 
  transverse, 
  jagged, 
  dark 
  lines, 
  sometimes 
  wanting, 
  

   except 
  on 
  the 
  front 
  edge 
  of 
  the 
  wing, 
  where 
  they 
  are 
  always 
  more 
  dis- 
  

   tinct, 
  dividing 
  this 
  portion 
  of 
  the 
  wing 
  into 
  four 
  very 
  nearly 
  equal 
  parts; 
  

   they 
  have 
  also 
  a 
  somewhat 
  jagged, 
  pale, 
  submarginal 
  line. 
  The 
  upper 
  

   surface 
  is 
  brownish-gray 
  in 
  color, 
  while 
  the 
  hind 
  wings 
  are 
  pale 
  ash 
  or 
  

   very 
  light 
  gray, 
  with 
  rarely 
  any 
  dots 
  or 
  markings. 
  Some 
  specimens 
  have 
  

   no 
  dots 
  whatever, 
  even 
  when 
  fresh 
  from 
  the 
  chrysalis 
  ; 
  and 
  captured 
  speci- 
  

   mens, 
  owing 
  to 
  the 
  looseness 
  of 
  the 
  scales, 
  always 
  have 
  the 
  marks 
  more 
  or 
  

   less 
  effaced. 
  Indeed, 
  the 
  ornamentation 
  of 
  the 
  wings 
  is 
  extremely 
  vari- 
  

   able. 
  In 
  many 
  specimens 
  the 
  middle 
  portion 
  of 
  the 
  front 
  wings, 
  within 
  the 
  

   three 
  dusky 
  lines, 
  is 
  quite 
  pale 
  and 
  mottled 
  with 
  grayish- 
  green, 
  while 
  the 
  

   basal 
  and 
  terminal 
  portions 
  are 
  marked 
  with 
  brown, 
  thus 
  making 
  the 
  

   contrast 
  greater. 
  

  

  Female. 
  — 
  The 
  body, 
  legs, 
  and 
  antennae 
  of 
  the 
  female 
  are 
  clothed 
  

  

  » 
  Monograph 
  of 
  the 
  Geometiid 
  Moths, 
  1876, 
  p. 
  404. 
  

  

  