﻿9.— 
  EESULTS 
  OF 
  INVESTIGATION 
  OF 
  BIONOMICS 
  OF 
  PLAT- 
  

   YEDRA 
  GOSSYPIELLA, 
  SAUNDERS, 
  IN 
  SOUTH 
  INDIA, 
  

   TOGETHEH 
  WITH 
  SOME 
  NOTES 
  ON 
  EARIAS 
  INSULANA 
  

   AND 
  E. 
  FABIA. 
  

  

  (Plates 
  XIII— 
  XV.) 
  

   By 
  E. 
  Ballard, 
  B.A., 
  F.E.S., 
  Government. 
  Entomologist, 
  Madras. 
  

  

  The 
  early 
  history 
  of 
  Platyedra 
  gossypiella 
  has 
  been 
  dealt 
  with 
  at 
  length 
  

   by 
  Ballon 
  (1) 
  and 
  others 
  and 
  it 
  is 
  unnecessary 
  to 
  repeat 
  it 
  here. 
  Suffice 
  

   it 
  to 
  say 
  that 
  all 
  evidence 
  goes 
  to 
  show 
  that 
  it 
  is 
  an 
  insect 
  of 
  South 
  Asiatic 
  

   origin 
  which 
  has 
  spread 
  by 
  artificial 
  means 
  to 
  almost 
  all 
  countries 
  where 
  

   cotton 
  is 
  grown, 
  and 
  must 
  be 
  reckoned 
  as 
  one 
  of 
  the 
  major 
  pests 
  of 
  the 
  

   world. 
  It 
  has 
  been 
  known 
  under 
  a 
  variety 
  of 
  names, 
  Depressaria 
  gossy- 
  

   piella, 
  Platyedra 
  gossypiella, 
  Gelechia 
  gossypiella 
  and 
  Pectinophora 
  gossy- 
  

   piella. 
  It 
  is 
  commonly 
  called 
  the 
  Pink 
  Boll-worm, 
  but 
  it 
  must 
  not 
  be 
  

   inferred 
  from 
  this 
  name 
  that 
  all 
  caterpillars 
  found 
  in 
  a 
  cotton 
  boll 
  are 
  

   the 
  larvae 
  of 
  Platyedra 
  gossypiella. 
  There 
  is 
  a 
  small 
  pink 
  caterpillar 
  of 
  the 
  

   genus 
  Pyroderces^ 
  which 
  does 
  no 
  harm 
  but 
  is 
  a 
  scavenger 
  ; 
  and 
  the 
  

   larva 
  of 
  a 
  Noctuid 
  moth, 
  Diparopsis 
  castanea, 
  Hmp., 
  which 
  is 
  a 
  true 
  

   boll- 
  worm 
  in 
  that 
  it 
  damages 
  seed 
  and 
  lint. 
  The 
  latter 
  insect 
  will 
  not 
  

   however 
  be 
  met 
  with 
  in 
  South 
  India, 
  as 
  it 
  is 
  a 
  native 
  of 
  Africa 
  and 
  need 
  

   not 
  therefore 
  concern 
  us 
  further. 
  Until 
  recent 
  years 
  P. 
  gossypiella 
  

   was 
  not 
  looked 
  on 
  as 
  a 
  very 
  serious 
  pest 
  of 
  cotton 
  in 
  South 
  India 
  and 
  

   received 
  little 
  or 
  no 
  attention. 
  No 
  statistics 
  exist 
  with 
  which 
  one 
  can 
  

   compare 
  its 
  present 
  depredations. 
  

  

  The 
  primary 
  cotton 
  pest 
  was 
  supposed 
  to 
  be 
  the 
  " 
  Spotted 
  boll- 
  

   worm," 
  the 
  two 
  species 
  of 
  Earias, 
  E. 
  fahia 
  and 
  E. 
  insulana. 
  It 
  was 
  also 
  

   stated 
  that 
  exotic 
  cottons 
  suffered 
  more 
  from 
  P. 
  gossijpiella 
  than 
  country 
  

   cottons, 
  the 
  latter 
  being 
  supposed 
  to 
  be 
  almost 
  free 
  from 
  attack 
  and 
  it 
  

   will 
  be 
  shown 
  that 
  in 
  some 
  instances 
  this 
  belief 
  is 
  not 
  altogether 
  in 
  accord- 
  

   ance 
  with 
  the 
  facts. 
  

  

  Attention 
  was 
  first 
  drawn 
  to 
  P. 
  gossypiella 
  in 
  Madras 
  Presidency 
  

   by 
  the 
  serious 
  deterioration 
  of 
  the 
  Cambodia 
  cotton 
  crop 
  in 
  1917-18 
  

   and 
  in 
  1919 
  it 
  was 
  proclaimed 
  as 
  a 
  pest 
  under 
  the 
  Agricultural 
  Pests 
  

   and 
  Diseases 
  Act, 
  which 
  was 
  put 
  into 
  force 
  in 
  Coimbatore 
  District 
  where 
  

   a 
  large 
  area 
  was 
  under 
  Cambodia 
  cotton. 
  Ordinarily 
  Cambodia 
  cotton 
  

  

  * 
  Pyroderces 
  coriacella, 
  Snell. 
  

   ( 
  70 
  ) 
  

  

  