﻿ARMY 
  WORM: 
  SEXUAL 
  DIFFERENCES. 
  103 
  

  

  with 
  confluent 
  fuscous 
  dots 
  ; 
  marked 
  longitudinally 
  by 
  two 
  dark 
  lines 
  that 
  commence 
  

   at 
  the 
  corners 
  of 
  the 
  mouth, 
  approach 
  each 
  other 
  towards 
  the 
  center, 
  and 
  again 
  recede 
  

   behind 
  ; 
  on 
  each 
  side 
  are 
  four 
  minute, 
  polished, 
  black 
  eyelets, 
  placed 
  on 
  a 
  light, 
  cres- 
  

   cent-shaped 
  ridge, 
  and 
  from 
  each 
  side 
  of 
  this 
  light 
  ridge 
  a 
  dark 
  mark 
  extends 
  more 
  

   or 
  less 
  among 
  the 
  confluent 
  spots 
  above. 
  Cervical 
  shield 
  polished 
  and 
  mottled 
  like 
  

   the 
  head, 
  with 
  the 
  white 
  medio-dorsal 
  and 
  upper 
  lateral 
  lines 
  running 
  conspicuously 
  

   through 
  it. 
  Anal 
  plate 
  obsolete." 
  Length, 
  1^ 
  inches 
  (38™">). 
  

  

  " 
  These 
  descriptions 
  apply 
  to 
  the 
  average 
  specimens, 
  but 
  there 
  is 
  considerable 
  varia- 
  

   tion 
  in 
  all 
  stages." 
  

  

  THE 
  PUPA. 
  (PI. 
  I, 
  Fig. 
  4.) 
  

  

  The 
  pupa 
  is 
  of 
  a 
  shiny 
  mahogany-brown 
  color, 
  with 
  two 
  stiff, 
  converging, 
  black 
  

   thorns 
  at 
  its 
  anal 
  end, 
  and, 
  each 
  side 
  of 
  the 
  thorns, 
  two 
  flne 
  curled 
  hooks. 
  It 
  is 
  from 
  

   18™™ 
  to 
  20 
  ™™ 
  (f 
  of 
  an 
  inch) 
  in 
  length, 
  and 
  is 
  rather 
  stout 
  ; 
  in 
  other 
  respects 
  not 
  dif- 
  

   fering 
  decidedly 
  from 
  allied 
  species. 
  

  

  THE 
  MOTH. 
  (PL 
  I, 
  Fig. 
  1, 
  a.) 
  

  

  The 
  parent 
  moth 
  is 
  variable 
  in 
  size, 
  the 
  average 
  individual 
  measuring 
  about 
  40™™ 
  

   (an 
  inch 
  and 
  a 
  half) 
  in 
  wing 
  expanse. 
  The 
  front 
  wings 
  are 
  pointed 
  at 
  the 
  tips, 
  and 
  

   are 
  of 
  a 
  reddish 
  gray 
  or 
  fawn 
  color, 
  much 
  specked 
  with 
  black 
  atoms. 
  Anterior 
  of 
  

   the 
  center 
  of 
  each 
  wing 
  are 
  two 
  rather 
  large, 
  indistinct 
  spots, 
  distinguished 
  from 
  the 
  

   rest 
  of 
  the 
  wing 
  by 
  an 
  absence 
  of 
  black 
  specks, 
  and 
  by 
  a 
  clearer 
  reddish 
  coloring. 
  

   Immediately 
  posterior 
  to 
  the 
  outermost 
  of 
  these 
  spots 
  is 
  a 
  white 
  point 
  indistictly 
  sur- 
  

   rounded 
  by 
  blackish. 
  A 
  series 
  of 
  black 
  points 
  parallel 
  with 
  the 
  outer 
  margin; 
  one 
  

   on 
  each 
  vein 
  is 
  usually 
  perceptible. 
  An 
  oblique 
  black 
  streak 
  starts 
  from 
  this 
  line 
  of 
  

   dots, 
  and 
  ascends 
  to 
  the 
  apex 
  of 
  the 
  wing, 
  and, 
  with 
  the 
  form 
  of 
  the 
  wings, 
  princi- 
  

   pally 
  characterizes 
  the 
  species. 
  Just 
  inside 
  the 
  fringe 
  is 
  a 
  serious 
  of 
  black 
  dots, 
  one 
  

   between 
  each 
  two 
  veins. 
  The 
  hind 
  wings 
  are 
  translucent, 
  gray, 
  with 
  the 
  terminal 
  

   border 
  and 
  the 
  nervures 
  blackish 
  (in 
  the 
  front 
  wings 
  the 
  nervures 
  are 
  whitish). 
  The 
  

   sexes 
  differ 
  from 
  each 
  other 
  but 
  little. 
  

  

  The 
  under 
  side 
  of 
  the 
  wings 
  is 
  of 
  an 
  opalescent 
  yellowish 
  white. 
  Along 
  the 
  outer 
  

   margin, 
  particularly 
  of 
  the 
  hind 
  wings, 
  are 
  many 
  black 
  specks, 
  so 
  nearly 
  confluent 
  as 
  

   to 
  form 
  a 
  definitely 
  limited 
  dusky 
  terminal 
  band. 
  On 
  the 
  costal 
  margin 
  of 
  each 
  fore- 
  

   wing, 
  near 
  the 
  tip, 
  is 
  a 
  small, 
  distinct, 
  black 
  dot, 
  and 
  at 
  the 
  center 
  of 
  each 
  hind- 
  wing 
  

   is 
  a 
  similar 
  dot. 
  The 
  body 
  is 
  coucolorous 
  with 
  the 
  wings, 
  and 
  the 
  legs 
  are 
  light 
  gray, 
  

   elightlj 
  tinged 
  with 
  reddish,. 
  and 
  speckled 
  with 
  black 
  dots. 
  

  

  SEXUAL 
  DIFFERENCES. 
  

  

  "As 
  tlirowiug 
  light 
  on 
  the 
  mode 
  of 
  oviposition 
  the 
  sexual 
  charac- 
  

   teristics 
  interest 
  us. 
  The 
  sexes 
  at 
  first 
  glance 
  are 
  not 
  easily 
  distin- 
  

   guished. 
  There 
  are 
  no 
  colorational 
  diiierences, 
  nor 
  does 
  the 
  abdomen 
  

   of 
  the 
  one 
  sex 
  differ 
  materially 
  in 
  size 
  or 
  form 
  from 
  that 
  of 
  the 
  other. 
  

   Yet 
  a 
  careful 
  examination 
  with 
  an 
  ordinary 
  lens 
  will 
  enable 
  one 
  to 
  sep- 
  

   arate 
  them 
  with 
  sufficient 
  certainty 
  by 
  the 
  smoother 
  antennae 
  (Plate 
  1, 
  

   Fig. 
  1^ 
  e) 
  and 
  more 
  pointed 
  abdomen 
  (Fig. 
  1, 
  h) 
  of 
  the 
  female, 
  compared 
  to 
  

   the 
  more 
  hairy 
  or 
  ciliate 
  antennae 
  (Fig. 
  1, 
  d) 
  and 
  blunter 
  abdomen 
  of 
  the 
  

   male 
  (Fig. 
  1, 
  a). 
  The 
  antennae 
  of 
  the 
  female 
  will 
  generally 
  be 
  found 
  quite 
  

   naked 
  toward 
  the 
  base, 
  while 
  those 
  of 
  the 
  male 
  show 
  two 
  rows 
  of 
  stiff 
  

   hairs, 
  about 
  half 
  as 
  long 
  as 
  the 
  antennal 
  width. 
  In 
  both 
  sexes 
  the 
  tip 
  

   of 
  the 
  abdomen 
  is 
  covered 
  with 
  a 
  brush 
  of 
  long, 
  pale 
  hairs, 
  and 
  the 
  mo- 
  

   ment 
  these 
  are 
  brushed 
  away 
  the 
  sex 
  is 
  at 
  once 
  easily 
  ascertained. 
  

   Suppose, 
  now 
  we 
  pick 
  out 
  a 
  male 
  for 
  examination! 
  A 
  little 
  friction 
  

  

  