﻿752 
  

  

  EEPORT 
  UNITED 
  STATES 
  GEOLOGICAL 
  SURVEY. 
  

  

  fl 
  

  

  toward 
  the 
  middle 
  of 
  the 
  wiug, 
  the 
  third 
  tooth 
  being 
  at 
  the 
  end 
  of 
  the 
  band. 
  There 
  

   is 
  a 
  row 
  of 
  dark 
  dots 
  along 
  the 
  outer 
  edge 
  of 
  the 
  stripe 
  ; 
  a 
  row 
  of 
  blackish 
  dots 
  along 
  

   a 
  pale 
  shade 
  just 
  outside 
  of 
  the 
  front 
  edge 
  of 
  the 
  wiug, 
  aud 
  two 
  diverging 
  rows 
  of 
  ; 
  i 
  

   blackish 
  dots 
  diverging 
  upon 
  the 
  tip 
  or 
  apex 
  of 
  the 
  wing. 
  The 
  fringe 
  is 
  marked 
  with 
  1 
  

   a 
  few 
  dark 
  spots. 
  The 
  middle 
  of 
  the 
  wing 
  next 
  the 
  white 
  band 
  is 
  darker 
  than 
  the 
  front 
  

   edge, 
  while 
  a 
  faint 
  yellowish 
  shade 
  runs 
  along 
  the 
  middle 
  of 
  the 
  outer 
  half 
  of 
  the 
  wing 
  

   toward 
  the 
  tip, 
  inclosing 
  a 
  few 
  black 
  dots. 
  It 
  expands 
  a 
  little 
  over 
  half 
  an 
  inch. 
  

  

  Remedies. 
  — 
  Should 
  young 
  plants 
  be 
  attacked 
  by 
  the 
  worms, 
  the 
  best 
  

   remedy 
  would 
  be 
  to 
  shower 
  them 
  with 
  soap-suds. 
  For 
  the 
  autumnal 
  

   brood 
  of 
  worms 
  the 
  plants 
  should 
  be 
  plentifully 
  showered 
  ; 
  and 
  if 
  this 
  is 
  

   not 
  efficacious, 
  the 
  worms, 
  and 
  the 
  cocoons 
  especially, 
  should 
  be 
  picked 
  

   off 
  by 
  hand. 
  

  

  The 
  Cabbage 
  Plusia, 
  Plusia 
  brassicce 
  Riley. 
  (Fig. 
  25.)— 
  In 
  August 
  and 
  September^ 
  

   gnawing 
  large, 
  irregular 
  holes 
  in 
  the 
  leaves; 
  a 
  rather 
  large, 
  pale-green 
  caterpillar, 
  

  

  marked 
  with 
  still 
  paler, 
  more 
  opaque 
  

   lines, 
  and 
  with 
  three 
  pairs 
  of 
  abdomi- 
  

   nal 
  feet, 
  being 
  a 
  semilooper, 
  and 
  

   changing 
  to 
  a 
  grayish-brown 
  moth, 
  

   whose 
  wings 
  are 
  marked 
  with 
  a 
  dis- 
  

   tinct 
  silver 
  interrogation 
  mark. 
  

  

  This 
  caterpillar 
  has 
  been 
  

   found 
  by 
  Mr. 
  Eiley 
  to 
  do 
  con- 
  

   siderable 
  mischief 
  in 
  Missouri. 
  

   I 
  quote 
  his 
  account 
  of 
  its 
  ap- 
  

   pearance 
  and 
  habits: 
  

  

  "In 
  the 
  month 
  of 
  August 
  

   and 
  September, 
  the 
  larvae 
  may 
  

   be 
  found 
  quite 
  abundant 
  on 
  

   this 
  plant, 
  gnawing 
  large, 
  ir- 
  

   regular 
  holes 
  in 
  the 
  leaves. 
  It 
  

   is 
  a 
  pale- 
  green 
  translucent 
  

   worm, 
  marked 
  longitudinally 
  

   Fig. 
  25.— 
  Cabbage 
  Plusia. 
  a, 
  caterpillar, 
  &, 
  pupa 
  ^ith 
  still 
  paler, 
  more 
  opaque 
  

   in 
  its 
  cocoon, 
  c, 
  moth. 
  After 
  Riley. 
  u^gg^ 
  ^nd, 
  like 
  all 
  the 
  kuown 
  

  

  larv8B 
  of 
  the 
  family 
  to 
  which 
  it 
  belongs, 
  it 
  has 
  but 
  two 
  pair 
  of 
  abdominal 
  

   prolegs, 
  the 
  two 
  anterior 
  segments, 
  which 
  are 
  usually 
  furnished 
  with 
  

   such 
  legs 
  in 
  ordinary 
  caterpillars, 
  not 
  having 
  the 
  slightest 
  trace 
  of 
  any. 
  

   Consequently, 
  they 
  have 
  to 
  loop 
  the 
  body 
  in 
  marching, 
  as 
  represented 
  

   in 
  the 
  figure, 
  and 
  are 
  true 
  'span-worms.' 
  Their 
  bodies 
  are 
  very 
  soft 
  and 
  

   tender, 
  and 
  as 
  they 
  live 
  exposed 
  on 
  the 
  outside 
  of 
  the 
  plants, 
  and 
  often 
  

   rest 
  motionless, 
  with 
  the 
  body 
  arched, 
  for 
  hours 
  at 
  a 
  time, 
  they 
  are 
  espied 
  

   and 
  devoured 
  by 
  many 
  of 
  their 
  enemies, 
  such 
  as 
  birds, 
  toads, 
  &c. 
  They 
  

   are 
  also 
  subject 
  to 
  the 
  attacks 
  of 
  at 
  least 
  two 
  parasites, 
  aud 
  die 
  very 
  

   often 
  from 
  disease, 
  especially 
  in 
  wet 
  weather 
  ; 
  so 
  that 
  they 
  are 
  never 
  

   likely 
  to 
  increase 
  quite 
  as 
  badly 
  as 
  the 
  butterflies 
  just 
  now 
  described. 
  

  

  '' 
  When 
  full-grown, 
  this 
  worm 
  weaves 
  a 
  very 
  thin, 
  loose, 
  white 
  cocoon, 
  

   sometimes 
  between 
  the 
  leaves 
  of 
  the 
  plant 
  on 
  which 
  it 
  fed, 
  but 
  more 
  

   often 
  in 
  some 
  more 
  sheltered 
  situation, 
  and 
  changes 
  to 
  a 
  chrysalis, 
  

   which 
  varies 
  from 
  a 
  pale 
  yellowish-green 
  to 
  brown, 
  and 
  has 
  a 
  consider- 
  

   able 
  protuberance 
  at 
  the 
  end 
  of 
  the 
  wing 
  and 
  leg 
  cases, 
  caused 
  by 
  the 
  

   long 
  proboscis 
  of 
  the 
  inclosed 
  moth 
  being 
  bent 
  back 
  at 
  that 
  point. 
  

   This 
  chrysalis 
  is 
  soft, 
  the 
  skin 
  being 
  very 
  thin, 
  and 
  it 
  is 
  furnished 
  at 
  

   the 
  extremity 
  with 
  an 
  obtuse 
  roughened 
  projection 
  which 
  emits 
  two 
  con- 
  

   verging 
  points, 
  and 
  several 
  short, 
  curled 
  bristles, 
  by 
  the 
  aid 
  of 
  which 
  

   it 
  is 
  enabled 
  to 
  cling 
  to 
  its 
  cocoon. 
  

  

  "The 
  moth 
  is 
  of 
  a 
  dark 
  smoky-gray, 
  inclining 
  to 
  brown, 
  variegated 
  

   with 
  light 
  grayish-brown, 
  and 
  marked 
  in 
  the 
  middle 
  of 
  each 
  front 
  wing 
  

  

  