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Indian  Insect  Pests. 


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Indian  Insect  Pests. 


^A 


BY 


H.  MAXWELL-LEFROY,  M.A.,  F.E.S.,  F.Z.5., 

Imperial  Entomologist 


I  I 


{  CALGUTTA :      ''      ' 

OFFICE  OF  THE  SUPERINTENDENT  ^OjF  GON^|flKMMENT  PRINTING,  INDIA. 

1906. 

Price    Re.  1-8  or  2s. 


St.  Albans, 
25th  Septemhcr  iSS^. 

'But,  meanwhile,  I  may  most  truly  say  that,  if  the  crop  or  timber  or  fruit 
growers  of  India  were  furnished  with  plain  and  comprehensive  accounts  of  history 
and  habits  of  the  common  insect  pests,  accompanied  by  wood-cut  figures,  so  as  to 
convey  the  appearance  of  pests  without  wearis  ime  description  of  details,  all  this 
would  be  a  national  benefit,  repaying  the  outlay  a  hundred  times." 

ELEANOR  A.  ORMEROD. 


348456 


^a 


y 


INTRODUCTION. 


A  S  Mr.  Lefroy  lias  written  this  book  largely  at  my  instance, 
-**•  I  wish  to  attach  a  few  words  in  order  to  explain  its 
scope.  It  is  not  a  scientific  treatise  on  Entomology,  written 
for  the  use  and  training  of  Entomologists,  but  is  intended  to 
serve  the  more  humble  but  useful  purpose  of  a  manual  of 
]3ractical  information  for  the  use  of  the  intelligent  agricul- 
turist in  the  protection  of  his  crops  from  insect  pests.  It  is 
also  hoped  that  it  will  be  suitable  as  a  text-book  for  use  in 
Agricultural  Schools  and  Colleges,  all  of  whose  students 
should  acquire  a  working  knowledge  of  insect  pests  and  of 
the  practical  measures  possible  for  the  protection  of  crops. 
With  these  objects  in  view,  the  author  has  avoided,  wherever 
possible,  scientific  terminology,  using  simple  English  equi- 
valents which  can  easily  be  understood  by  persons  with  no 
scientific  training  in  Entomology. 

The  information  available  for  a  l3ook  of  even  this  limited 
scope  is  very  far  from  complete.  A  good  deal  of  work 
has  been  done  in  the  past  for  Systematic  Entomology  in  the 
collection  and  classification  of  some  groups  of  Indian  insects, 
more  particularly  the  Butterflies,  but  it  is  only  within  the 
past  few  years  that  any  real  inquiry  has  been  made  into 
Economic  Entomology,  dealing  with  insect  pests  and  their 
treatment.  Eor  this  reason  Mr.  Lefroy  would  prefer  to  post- 
pone publication  until  the  material  at  his  disposal  is  more 
complete,  but  I  think  first,  that  the  information  available  is 
already  of  sufficient  importance  to  give  to  the  public,  and 
second,  that  the  best  way  of  collecting  additional  information 
is  to  interest  persons  in  that  already  acquired  and  to  show 


iv  INTRODUCTION. 

clearly  the  need  for  further  help.  Por  this  purpose  the  many 
blanks  in  this  book  have  designedly  been  given  prominence 
by  the  author  in  the  hope  that  many  workers  will  endeavour 
to  fill  them  up  by  careful  and  intelligent  study  of  insect 
life.  The  field  for  future  investigation  is  unlimited.  This 
book  is  a  testimony  to  the  strenuous  efforts  made  during  the 
past  three  years  in  this  field  by  Mr.  Lefroy,  who  is  the  only 
Entomologist  in  the  Department  of  Agriculture.  It  is  hoped 
that  in  the  near  future  an  entomologist  may  be  employed  by 
each  important  province  for  the  investigation,  prevention  and 
cure  of  crop  pests,  but  this  will  not  lessen  the  need  for  other 
workers,  whose  assistance  will  be  warmly  welcomed  by  the 
Government  Entomologist.  If  this  help  is  freely  given,  I 
look  forward  within  a  few  years  to  the  issue  of  a  revised 
edition  of  this  book,  in  which  still  more  useful  information 
about  insect  pests  may  be  given. 

E.  G.  SLY, 

Officiating  Inspector-G eneral 

of  Agriculture  in  India. 
The  1st  May  1906. 


PREFACK. 


THE  study  of  pests  in  India  dates  back  twenty  years  to  the 
formation  of  the  Entomological  section  of  the  Indian 
Museum,  the  commencement  of  Indian  Museum  Notes,  and 
the  publication  of  Surgeon- General  Balfour's  little  volume, 
"  The  Agricultural  Pests  of  India."  During  this  time  a 
continuous  effort  has  been  made  to  classify  insects  injurious 
to  crops,  terminating  with  the  work  of  the  late  Mr.  L. 
deNiceyille,  the  first  Entomologist  to  the  Government  of  India. 
It  has  fallen  to  me  to  gather  up  these  records,  to  supplement 
them  by  observation  in  the  field,  and  to  put  together  briefly 
what  is  known  of  Indian  pests. 

To  any  one  familiar  with  the  scattered  records  of  Indian 
Museum  Notes,  such  an  undertaking  was  a  necessary  pre- 
liminary to  further  work  and,  above  all,  to  the  wider  growth 
of  the  study  of  insect  pests.  Eew  oljservers  have  contributed 
to  our  knowledge  of  insect  pests  in  India,  which  is  deplorable 
in  so  vast  a  continent  where  so  large  a  population  is  depen- 
dent on  agricidture. 

In  the  present  volume  I  have  tried  to  give  a  short 
account  of  the  general  features  of  the  lives  of  insects,  as  well 
as  the  salient  facts  concerning  our  destructive  pests.  Those 
who  wish  for  technical  accounts  of  the  anatomy  and  classi- 
fication of  insects  will  find  abundance  of  excellent  books. 
We  are  here  more  closely  concerned  with  their  living 
activities  and  the  part  played  l3y  them  in  the  reduction  of 
the  yield  of  the  staple  crops  of  the  country. 

I  trust  that  the  book  may  be  of  service  to  many  who  are 
engaged  in  agriculture  and  horticulture.  Insects  are  universal 
and  quite  interesting  as  soon  as  one  ceases  to  regard  them  as 
mysteries.     I  cannot  hope  to  emulate  the  living  interest  of 


VI  PREFACE. 


the  insect  world  as  presented  by  '' Eha,"  but  perhaps  the 
necessary  precision  oO  thought  and  language  in  this  volume 
may  blend  with  his  delightful  pictures  and  help  to  give  a 
true  impression  of  our  insect  friends  and  foes. 

Much  of  the  local  information  in  this  volume  has  been 
obtained  from  the  many  reports  sent  in  at  the  instance  of  the 
Directors  of  Agriculture.  In  a  country  where  nothing  is 
outside  the  scope  of  official  enquiry,  much  may  be  learnt 
from  enquiries  pursued  by  the  Mamlatdar  or  Tahsildar,  and 
especially  in  regard  to  the  attitude  of  the  cultivator  towards 
his  pests.  My  acknowledgments  are  due  to  the  many  dis- 
trict officials  who  have  sent  in  reports  of  injurious  insects 
and  carefully  collected  information  as  to  the  remedies  in  use 
among  the  ryots, 

I  am  under  a  deep  obligation  to  Mr.  P.  G.  Sly,  Officiating 
Inspector  General  of  Agriculture,  to  whom  the  inception 
of  the  book  is  due,  and  ayIio  lias  endeavoured  to  bring  the 
arransrement  and  text  into  the  form  most  suitable  for  those 
for  whom  it  is  intended ;  without  this  encouragement  and 
advice,  the  volume  could  not  have  been  produced  in  its 
present  form.  I  have  also  to  thank  Mr.  0.  A.  Barber,  Gov- 
ernment Botanist,  Madras,  and  Dr.  H.  H.  Mann,  Scientific 
Officer  to  the  Indian  Tea  Association,  for  valuable  help  and 
suggestions  in  the  final  preparation  of  the  text.  The  illustra- 
tions are  largely  the  work  of  the  late  artist  in  the  Indian 
Museum,  Babu  G.  C.  Chukraburtty,  and  these  have  in  many 
cases  been  published  in  another  form  in  the  pages  of  Indian 
Museum  Notes.  Others  have  been  prepared  under  my  super- 
vision by  H.  H.  .Deboo,  Chotalal  Daulatram  Shah  and 
Eambliau  Balajee,  artists  attached  to  the  Department 
of  Agriculture.  The  diagrams  and  photos  are  my  Qwn, 
and  Mr.  H.  C.  Wood  very  kindly  prepared  tlie  design  on 
the  cover. 

I  am  indebted  to  the  work  of  my  staff  for  many  observa- 
tions ;  the  Entomological  Assistants  attached  to  the  Depart- 
ments of  Agriculture  in  the  Punjab,  Central  Provinces  and 


Baroda  have  added  inrormatioii  concerning'  injurious  pests, 
and  I  have  incorporated  their  o])servations  in  some  cases.  I 
trust  that  many  will  be  found  to  follow  in  their  footsteps, 
to  take  up  the  study  of  insect  life  in  relation  to  agriculture 
in  India,  and  to  devote  themselves  to  this  In'anch  of  research. 
It  is  certain  that  India  should  not  be  behind  other  nations  in 
scientific  knowledge,  and  that  men  can  be  found  who  will 
devote  themselves  to  this  form  of  learning,  not  for  the  sake 
of  the  pay  or  position,  bnt  at  the  bidding  of  that  intense 
organised  curiosity  which  lies  at  the  root  of  modern  science. 
I  venture  to  hope  that  this  volume  may  draw  others  into  this 
work  and  open  a  new  field  for  research. 

H.  MAXWELL-LEFROY, 

Imperial  F.tiiomolofjiat. 


CONTENT'S. 


Part  1.— Insects  in  General 

Chaptek  I. — Insects  :  their  structure  and  food    . 

„  II. — Life  history  and  habits  .... 

„  III. — Form  and  colour  ..... 

IV. — Classification  and  nomenclature 


Fage 
1 

15 

34 
52 


Part  II.— Preventive  and  Remedial  Measures. 

Chapter        Y. — Origin  of  insert  pests    .         . 
„  TI. — Preventive  and  remedial  measui'es 

„  VII. — Insecticides  and  spraying 

Part  III.— Insects  Injurious  to  Crops 

Chaptee  "VIII. — Pests  of  the  cotton  plant 
„  IX. — Pests  of  rice  and  wheat 

„  X. — Pests  of  cane,  maize,  and  sorghum 

„  XI. — Pests  of  leguminous  crops 

„  XII. — Pests  of  miscellaneous  field  crops 

„         XIII. — Pests  of  vegetable  crops 

XIV.— Pests  of  fruit        . 
„  XV. — Caterpillar  pests  , 

„  XVI. — Beetle  pests  .  .  . 

„        XVII. — Locusts,  gi-asshoppers,  surface  beetles,  and  burrowing  insects 
„      XVIII. — Sucking  insects    ........ 


63 

68 
75 


89 
114 
125 
140 
151 
163 
170 
181 
196 
210 
233 


Part  IV.— Other  Important  Insects. 


Chjptek    XIX. — Insects  infesting  grain 
„  XX. — Insects  attacking  cattle 

,,  XXI. — Beneficial  insects 


Appendix    A. — Useful  informaiiou 

„  B. —  Collecting,  pinning,  setting 


251 
261 
268 

283 
290 


Ge>-ekai  Index 305 

List  of  Illustrations    .........   311 

List  op  Plants  ...........   315 


Part  I. 


INSECTS    IN    GENERAL 


CHAPTER   I. 


Fia.  1, 
A  Millipede — {not  an  insect). 


INSECTS  :  THEIR  STRUCTURE  AND  FOOD. 

THE  word  insects  recalls  the  many  familiar  butterflies,  beetles  and 
other  flying  or  crawling-  creatures  that  are  so  abundant.    The  term  is, 

however,  very   loosely   used 

and  inchides  many  crawling" 

creatures  that  are  not  insects 

in    the   strict   sense   of   the 

word,  and  with  which  this 

volume    does   not  deal.     It 

is  not  easy  to  give  a  clear 

idea  of  the  animals  included 

in  the   great   class   Insecta. 

Excepting"  birds  and  bats,  insects  alone  can   fly;  but  only  a  proportion 

of   the   insects   one   commonly   sees   have   reached   the  flying  stage  or 

ever  fly.     We  must,  therefore,  look  for  better  distinguishing  characters. 

The   legs   will   help   us.     A  great  host  of  small  creatures  that   crawl 

on    earth   have   distinct   small   jointed  legs.      One   thinks    of    spiders, 

of    centipedes,    of    millipedes,    of    scorpions,     as    well    as    of    beetles, 

caterpillars  and  the 
like.  Of  these,  in- 
sects have  never 
more  than  three 
pairs  of  legs.  A 
centipede  with  over 
40  legs  is  not  an 
insect,  nor  is  a  milli- 
pede. A  spider  with 
four  pairs  is  not  an 
insect,  nor  is  a  scor- 
pion. On  the  other 
hand,  a  caterpillar 
is,  though  it  seems 
to  have  many  legs; 
Pjq  2  actually  it  has  three 

Bed  Spider— {not  an  insect).  pairs  of  little  jointed 


2  INSECTS  :    THEIE    STRUCTURE   AND    FOOD. 

legs,  but  also  has  five  pairs  of  little  sucker-feet  to  enable  it  to  crawl 
along  a  leaf.  Our  insects  then,  if  they  have  no  wings,  should  certainly 
have  not  more  than  tliree  pairs  or  six  legs.  They  also  have  the  feelers 
on  the  front  of  the  head. 


Fig.  3. 
Ti/pical  Caterpillar. 

But  on  the  other  hand  there  are  maggots,  for  instance,  that  liave 
no  legs.  They  look  like  worms,  but  are  distinguished  by  many  small 
points  of  structure.  One  can  only  remember  that  a  maggot  is  one  stage 
in  the  life  of  an  insect  and  will  become  a  fly  with  wings  and  six  legs. 
There  are  also  insects  that  have  anything  but  the  general  form  of 
insects;  they  are  however  rare,  and  if  we  keep  clearly  in  our  minds  that 
spiders,  centipedes,  millipedes,  scorpions  and  such -like  eight  or  many- 
legged  creatures  are  not  insects,  we  are 
not  likely  to  be  confused.  For  those 
who  want  a  more  exact  and  scientific 
definition,  there  are  excellent  books 
on  zoology  and  comparative  anatomy, 
where  the  distinctions  are  expressed  in 
more  scientific  terms. 

An  insect's  body  is  completely 
clothed  in  hard  durable  material  within 
which  the  organs  He.  This  is  not  one 
continuous  covering,  but  is  formed  of 
rings  joined  end  to  end  by  flexible 
connections  so  as  to  enable  the  insects 
to  crawl  and  move  about.  These  rings 
overlap  a  little  and  so  present  an  un- 
broken hard  surface  to  the  outside.  Within  this  flexible  tube  of  rings 
lie  the  soft  parts,  the  muscles,  nerves  and  all  organs ;  attached  to  it  ax'e 
the  legs,  wings,  jaws,  and  other  parts. 


Fig.  4. 
An  insect  (beetle)   which  resembles  a 
mite,  but  has  three  pairs  of  legs. 


INSECT    STRUCTUKE. 


If  we  take  a  caterpillar  and  examine  it  we  find  the  following-  parts  : — 

The   head  is  rounded,  broadly  attached  to  the  body  ;  the  mouth  is 

situated  on  the  lower  side  with  a  complex   arrangement  of  jaws  ;  small 


THO'RA  X 


# 


nooTH 


i-fs 


^/  > 


iTi^Acie 


fce-r 


Fig.  5. 

eyes  are  set  in  a  half  circle  on  each  side  of  the  head ;  and  we  may  dis- 
cern a  pair  of  small  feelers  called  antenna.  Behind  the  head  are  three 
segments  (a  ring"  and  the  contents  are  called  a  segment),  each  having-  a 
pair  of  small  jointed  leg-s  below :  there  are  short  or  long-  hairs  on  each 
segment,  and  the  first  segment  often  has  a  small  oval  shield  just  behind  the 
upper  part  of  the  head.  These  three  segments  together  form  the  thorax. 
Behind  the  thorax  are  eight  segments   (which  form  the  aid  omen)  ^ 


HEAD 


ANTENNA 


> 


THORAX.  • 


ABDOMEN 


MOUTH 


SPIRACLE. 


SUCKER  FEET 


.SPIRACLE 


Fig.  6. 
JHagrc^m  of  Caterpillar. 


P    % 


4  INSECTS  :    THEIR   STRUCTURE   AND    FOOD. 

and  the  last  ono  ov  two  wl.icl.  wo  may  call  tlio  tail.  Tlieso  segments  are 
nearly  alike,  but  the  four  in  the  middle  usually  have  a  pair  of  small 
projeetions  on  which  are  hooks  ;  Ihese  are  sucker-feet  and  there  is  a  fifth 
l)aii-  on  the  tail.  Each  of  the  eight  segments  has  a  small  dark  spot  on  each 
side,  and  a  similar  si)ot  is  found  on  the  thorax  ;  these  s]wts  are  Higmata,'^ 

or  air  openings,  which  admit 
air  to  the  system  of  air  tubes 
inside  the  caterpillar^s  body. 
The  hairs  or  bristles  found  on 
the  segments  and  the  tail  are 
not  scattered  haphazard,  but 
arranged  in  a  definite  manner. 
These  are  the  salient  points 
that  can  be  seen  in  any  insect. 
In  all  insects  the  head,  the 
thorax  and  the  abdomen  are 
distinct ;  the  head  always  bears 
the  eyes,  the  mouth  and  jaws 
and  the  feelers  {antenna)  ; 
the  thorax  always  bears  the 
legs  and  the  wings  and  is 
actually  composed  of  three  segments,  though  we  cannot  always  see 
the  division ;  the  abdomen  bears  sucker-feet  in  some  insects  only  and 
has  a  varying  number  of  visible  segments  in  different  insects.  Stigmata, 
or  air  openings,  are  found  in  all  insects,  and  usually  are  arranged  as  in 
the  caterpillar. 

AH  insects  have  a  more  or  less  hard  covering,  which  is  composed  of 
a  substance  known  as  cJdtin  ;  this  is  a  nitrogenous  material,  peculiarly 
resistant  to  chemicals,  which  forms  an  impervious  covering.  The  legs, 
antenna?,  wings  and  all  parts  of  an  insect  are  covered  in  it ;  the  thick 
hard  wings  of  a  beetle,  the  fine  scales  of  a  butterfly  and  the  flexible  sldn 
of  a  caterpillar  are  largely  composed  of  it. 

Speaking  generally,  the  skeleton  of  an  insect  is  this  outer 
covering;  there  are  no  "bones,^'  but  a  few  chitinous  supports  of  the 
internal  organs.  When  an  insect  is  killed  and  dried  the  whole  body 
perishes  except  the  chitinous  covering,  so  that  a  pinned  collection 
only  consists  of  this  dried  cJiitin.  Such  insects  as  have  not  a  suffi- 
ciently thick  covering  must  be  kept  in  spirit,  so  that  the  internal 
organs  may  be  preserved  in  order  to  maintain  the  natural  form  of  the 
insect. 


Fig.  7. 

A  Wasp,  showing  the  divisions  of  the  body 

in  a  winged  insect. 


Stigma,  a  spot ;  plural,  stigmc^ta,  spots. 


WINGS    AND    MOUTII-l'AllTS. 


Fig.  S. 

Fit/,  to  show  the  second  ijair  of  loings 

reduced  to  halancers. 


In  distinguishing'  the  different  classes    of  insects,  it  is   necessary  to 

look  specially  at  the  wings  and  the 
mouth-parts.  In  mature  insects 
there  are,  as  a  rule,  two  pairs  of 
wing's  :  the  first  pair  (upper  or  fore- 
wings)  attached  above  the  second 
pair  of  legs,  the  second  (lower  or 
hind  wings)  attached  above  the 
third  pair  of  legs.  In  some  insects 
the  second  pair  of  wings  is  not 
present  or  is  transformed  into 
a  different  structure.  In  a  few 
the  wings  are  never  developed, 
the  mature  insect  being  wing- 
less or  having  imperfectly  de- 
veloped wings,  (rigs.  10,  30,  40 
and  51.) 

The  "  mouth-parts "  (jaws)  of  insects  are  the  structures  that  surround 
the  mouth  and  which  are  used  for  feeding.  These  structures  are  somewhat 
complicated  and  are  specially  formed  in  accordance  v/ith  the  habits  of  the 
insects.  Insects  that 
bite  leaves  or  green 
plants  have  short  bit- 
ing mouth-parts,  with 
cutting  teeth ;  insects 
that  attack  other 
insects  have  usually 
long  sharp  jaws,  suit- 
ed for  grasping  their 
l)rey ;  those  which 
suck  the  juice  of 
plants  have  a  slender 
tube-like  beak,  with 
sharp  instruments  for 
piercing  the  plant ; 
those  also  which  suck 
the  blood  of  animals 
or  insects  have  a  sharp  tubular  beak,  as  in  the  mosquito.  It  is  important 
t(^  be  able  to  recognise  the  differences  between  these  kinds.  A  few  have 
mouth-parts  not  included  in  either  of  the  above  kinds ;  thus  the  bees  have 
very  complicated  jaws,  which  are  litted  for   lapping  up  the   nectar  in 


Fig.  9. 
Head  of  a  Caterpillar,  from  heneafh. 
{From  Lijonnet^ 


iifSfeCTS  :    TUEIE    STRUCTtPvE   AND    FOOt). 


Fig.  10. 
Three  carnivorous  Beetles  ivith  long  mandibles. 


flowers  and  also  for  biting' ;  tlic  butterflies  and  moths  have  moutli-parlis 
formed  like  a  long  slender  tube  whicli  can  be  stretched  into  the  bottom  of 
flowers  to  extract  the  nectar.  Figures  11 — 15  will  show  the  appearance  of 
these  mouth-partsj  and  it  is  important  to  look  always  at  the  mouth-parts  of 
insects,  since  this  at  once  gives  a  clue  to  the  probable  habits  of  the  insect. 


MOUTH-PAHTS. 


...  C. 


Fig.  11. 

The  biting  mouth-parfs  of  a  CricTcef. 

a.   Vpferlif.     b.   The  stronr/ toothed  mandibles,     c.  The  sensoru  palps. 


Fig.  12. 

The  biting  mouth-parts  of  a  Beetle. 
a.    Upper  lip.     b.   The  strong  curved  mandibles,     c.  The'sensorg  palps. 


Fig.  13. 

The  sucking  mouth-parts 

of  JDiptera. 


Fig.  14. 

The  curled -up  proboscis 

of  a  Butterfly. 


Fig.  15. 
The  curled -up  pro- 
boscis of  a  Moth. 


8  ilsrsEcf  s :  tSeiu  structure  and  pood. 

The  bodies  of  insects  are  made  up  of  muscles,  nerves,  organs  and 
other  parts  just  as  other  animals  are,  and  they  live  in  a  very  similar  way. 
The  food  taken  in  at  the  mouth  passes  into  the  stomach,  and  is  dig-ested ; 
the  remains  are  excreted.  The  stomach  and  intestine  form  a  plain  long 
tube  which  passes  from  the  mouth  to  the  tail.  The  digested  food  passes 
into  the  space  between  the  skin  and  the  intestine,  in  which  all  the  muscles 
and  nerves  lie ;  above  the  stomach  and  intestine  there  is  a  small  heart, 
consisting  of  a  long  slender  tube  which  pulsates  and  pumps  the  dissolved 
food  forward  over  the  head  and  all  round  the  body ;  this  can  be  seen  in 
many  caterpillars,  if  the  upper  part  of  the  body  is  intently  watched  for 
some  minutes.  In  the  body  there  are  numerous  muscles,  which  enable 
the  insect  to  move.  In  the  head  there  is  a  small  brain,  and  running  down 
the  lower  side  of  the  body  there  is  a  double  cord  of  nerve  tissue,  with  little 
swellings  in  each  ring.  This  cord  is  like  our  own  spinal  cord,  and  from  it 
nerves  go  to  all  the  parts  of  the  body.  Insects  have  nerves  similar  to  our 
own  though  on  a  simpler  scale.  Besides  these  organs,  the  perfect  insect  has 
reproductive  organs,  male  or  female.  These  open  at  the  hind  end  of  the  body, 
just  below  the  opening  of  the  intestine.  In  many  insects  the  female  has 
attached  to  the  hind  end  of  the  body  a  special  instrument  for  laying  eggs ; 
the  sting  of  the  bee  is  really  the  egg-laying  instrument :  in  some  insects 
this  structure,  called  an  ovipositor,  is  very  large  and  conspicuous  (fig.  52). 

Insects  have  senses  and  sense  organs  which  we  may  compare  with 
those  of  other  animals,  though  we  cannot  pretend  to  understand  them. 

Eyes  take  the  form  either  of  a  pair  of  large  conspicuous  structures 
on  the  side  of  the  head  or  of  several  small  points  on  the  upper  surface  or 
side  of  the  head.  The  former,  known  as  compound  eyes,  we  may  consider 
as  hundreds  or  thousands  of  small  eyes  united  to  form  a  single  complex 
structure ;  we  can  see  these  separate  small  eyes  which  give  the  whole  eye 
a  honey-comb  appearance.  The  latter,  known  as  simple  eyes,  are  found 
in  caterpillars  and  other  immature  insects,  whicli  do  not  have  compound 
eyes,  and  also  in  many  mature  insects  in  conjunction  with  compound 
eyes.  The  caterpillar  has  five  or  six  such  eyes  on  each  side  of  the  head ; 
the  grasshopper  has  three  only,  some  bugs  have  two,  and  many  insects 
have  none.  The  function  of  eyes  is  not  clearly  understood,  but  it  is 
believed  that  the  compound  eyes  are  as  efficient  as  our  own  eyes,  and  that 
simple  eyes  perhaps  serve  to  distinguish  light  and  shade  or  act  in  some 
such  simple  manner.  '^ 

Organs  of  hearing  are  present  probably  in  many  insects,  but  definite 
organs  similar  to  our  ears  are  known  only  in  the  grasshoppers  and  their 
allies.  Many  other  insects  probably  hear  sounds,  since  many  of  them 
also  make  sounds,  but  it  is  not  certain  what  is  the  organ  of  hearing. 


SENSES.  9 

The  sense  of  smell  is  also  probably  present,  and  is  believed  to  lie  in  the 
antenna3.  Some  insects  [e.g.,  locusts)  can  almost  certainly  smell  water, 
a  feat  we  are  incapable  of  because  our  olfactory  organ  is  always  damp. 
Others  can  certainly  smell  flowers,  carrion,  etc.,  and  their  sense  of  smell 
is  probably  far  keener  than  our  own. 

Taste  is  believed  to  be  a  sense  functional  through  certain  organs  in 
the  mouth-parts. 

Touch  is  another  sense  probably  connected  specially  with  the  antennae 
and  the  little  palps  on  the  mouth-parts. 

Other  senses  that  we  do  not  now  use  certainly  occur ;  possibly  we 
were  once  possessed  of  the  "  sense  of  direction,"  as  many  insects  are ; 
other  obscure  senses  we  are  able  dimly  to  perceive  only  after  a  close  study 
of  the  habits  of  insects,  although  we  cannot  connect  any  special  sense 
organs  with  them.  Among  these  we  may  include  the  very  peculiar  sense 
shown  in  the  phenomenon  known  as  '^  assembling."  It  is  known  that  if 
the  females  of  certain  moths  are  exposed  in  a  cage,  the  males  of  those 
species  will  come  in  numbers  and  from  considerable  distances.  These  dis- 
tances in  some  cases  extend  to  several  miles.  By  what  sense  the  males 
become  aware  of  the  presence  of  the  female  is  not  known.  The  pheno- 
menon is  utilised  in  the  rearing  of  wild  silk  moths  in  India,  the  reared 
female  attracting  the  wild  males  from  the  jungle. 

It  is  impossible  to  discuss  the  senses  of  insects  in  further  detail  in 
this  book.  Man  cannot  hope  to  comprehend  them.  The  fact  that  a 
butterfly  knows  "  by  instinct "  the  i^lant  on  which  its  young  will  feed 
seems  marvellous  when  we  recollect  that  the  butterfly  could  not  remem- 
ber what  it  fed  on  as  a  caterpillar,  the  metamorphosis  having  come  after 
its  caterpillar  stage  and  obliterated  its  memory  of  larval  life.  There  are 
countless  instances  of  this  kind,  and  we  can  only  study  the  activities  of 
insect  life  with  admiration  at  the  wonderful  "instincts"  and  senses  with 
which  they  are  endowed. 

Among  other  curious  phenomena  may  be  marked  the  formation  and 
migration  of  swarms  of  insects,  such  as  locusts.  Tliis  phenomenon  is  also 
little  understood  ;  it  occurs  in  a  small  number  of  insects  belonging  to 
different  families.  The  locusts  are  the  best  known  instances  in  India, 
two  kinds  of  which  move  in  swarms  over  many  hundreds  of  miles.  It 
occurs  also  in  moths,  butterflies,  dragon-flies,  in  the  larvie  of  certain  flies 
and  in^caterpillars.  Large  numbers  of  these  insects  gather  together,  form 
swarms  and  migrate  from  place  to  place.  This  phenomenon  probably 
originates  in  the  necessity  of  moving  to  fresh  places  in  search  of  food. 
Insects  which  multii%  very  rapidly  into  enormous  numbers  may  have 
found  it  a  necessity  to  move  often,  the  habit  thus  becoming  a  settled  one. 


10 


INSECTS  :    THEIR    STIiUCTUEE   AND    FOOD. 


Food. 

From  the  moment  that  an  insect  hatches^  its  first  task  is  to  provide 
food  by  its  own  exertions ;  it  has  also  to  escape  the  enemies  and  dangers 
that  surround  it ;  lastly,  it  has  to  lay  eggs  in  the  proper  situation  and  in 
some  cases  must  provide  for  the  young.  These  are  the  three  prime  neces- 
sities of  the  insect^s  life,  and  though  in  many  cases  it  is  possible  that  the 
gratification  of  a  taste  for  other  pleasures  is  an  object  in  life,  we  may 
interpret   the    activities,   the  form,  colour   and   structure,   even    the   life 

history   of   insects   in   terms   of   these  three 
principal  needs. 

The  food  of  insects  is  extremely  diverse, 
and  it  is  not  always  clear  how  they  are  able 
to  extract  the  requisite  amount  of  nutriment 
from  the  substances  they  consume.  We  may 
at  once  abandon  the  idea  that  nutrition  is 
comparable  to  that  of  domestic  animals. 
Digestion,  nutrition  and  respiration  are  very 
different  in  insects.  What  proportion  of 
proteids,  carbohydrates  and  fats  is  necessary 
cannot  be  stated.  The  amount  of  food  or  of 
air  necessary  to  existence  may  be  reduced 
to  very  low  limits  since  insects  are  not 
Fig.  16.  warm-blooded ;   in   the  absence  of   muscular 

Wingless   Perfect    Insect :    the  activity   there  is  probably  uo  wastage  of  the 
insect  lives  on  the  surface  of  the     .  ••  it     „^,r^-„-,       n/^ 

sea  and  has  no   need  of  toings.  tissues,    no     consumption      of    oxygcn,    no 
{From  Distant)  elimination    of   water   or   of   waste  |)roducts. 

The  amount  of  food  or  oxygen  assimilated  may  be  measured  by  muscular 
activity  and  may  cease  entirely  when  this  ceases.  Bearing  this  in 
mind,  we  need  not  be  astonished  at  the  insects  which  live  solely  in 
dry  wood,  in  burrows  without  access  to  the  air,  or  which  feed  solely  on 
chillies,  opium  or  tobacco.  Such  insects  do  not  drinlc,  they  simply  eat, 
and  we  are  entirely  ignorant  of  their  digestive  and  nutritive  processes. 
Nor  is  it  astonishing  that  many  insects  can  live  for  many  months 
without  food. 

Most  insects  live  on  land,  a  few  on  or  near  the  sea,  many  in  fr>sh 
water.  Marine  insects  are  few  -,  some  in  the  sea  itself,  some  on  the 
surface,  a  larger  number  on  the  beach  or  in  rock-pools.  Eelatively,  the 
number  is  very  small,  and  sea  water  presents  an  almost  impervious 
obstacle  to  insect  life.    Fresh-water  ponds,  streams,  tanks,  and  other  supi^lies 


bOMINANCil. 


11 


o£  water  teem  with  insect  life.  Their  habits  are  of  great  interest,  and  the 
devices  with  which  they  supply  themselves  with  air  are  amazing*  in  their 
diversity  and  ingenuity.  Unquestionably  the  aquatic  insects  are  descended 
from  air-breathing  land  insects,  and  for  every  species  the  problem  of 
extracting  air  from  the  water  or  of  di'awing  a  supply  from  the  surface 
has  been  solved  in  a  more  or  less  ingenious  manner.  These  insects,  how- 
ever, form  a  division  apart,  cut  off  by  their  diverse  habits  from  the  insects 
living  on  dry  land. 

The  vast  majority  of  insects  live  on  the  land,  establishing  them- 
selves in  every  possible  situation,  with  the  most  diverse  occupations  and 
methods  of  obtaining  a  living.  At  this  period  of  the  earth^s  history 
they  are  the  dominant  group,  the  most  successful  and  prosperous,  taking 
toll  of  all  other  creatures.  In  number  of  species,  in  actual  numbers  or 
bulk,  in  the  sum  total  of  their  activities,  they  outweigh  all  other  forms  of 
animal  life  at  present  on  the  earth.  The  extraordinary  diversity  of  their 
habits  and  food,  their  rapid  multiplication,  their  small  size,  their  varied 
powers  of  locomotion,  of  offence  and  defence,  and  the  marvellous  instincts 
and  senses  with  which  they  are  endowed,  all  these  serve  to  put  them 
above  other  forms  of  animal  life.  Man  prides  himself  on  conquering 
nature,  on  being  the  highest  expression  of  animal  life,  the  crown  of  crea- 
tion :  a  dispassionate  examina- 
tion of  insect  life  reveals 
that   even    man's  powers    are 

as  nothing  to    those  of  insect 

life,    his     senses    weaker,    his 

sociology  and  conduct  of  life 

far  inferior  to  that  of  the  social 

insect,    and  he    himself    com- 
paratively     lacking    in      the 

exhibition  of  altruism  and  right 

conduct  shown  by  an  insect. 
Insects  are  small  and  their 

domination   is    not    ajiparent; 

but     they     have     established 

themselves  in  every  nook  and 

corner  of   the  earth,  deriving 

their  food  from  a  vast  number 

of    sources.     Many    feed     on 

plants,  living  in  every  part  of 

the  growing  plant,  from  the  fruit  to  the  roots ;  eating  the  flowers,  boring  in 

the  stem,  mining  in  the  leaves ;  they  devour  the  leaves,  destroy  the  bark  and 


^<;  ^ 

h 

-""■■■^  '-..• 

\ 
a    '^ 

Fig.  17. 

Piaffes  of  Fly   ivhose  maggot  lives   in  the  leaf  of 

the  tea-plant, 

{From  drawing  hy  E,  E.  Green.) 


1 2  INSECTS  :    THEIR   STRtlCTUHE  AND   POOD. 

eat  the  roots  ;  tliey  suck  out  the  sap  and  live  as  parasites  upon  all  parts  of 
the  plant.  Perhaps  one-third  of  the  total  number  of  insects  live  on  plant 
life  directly,  thus  constituting  one  big"  division  called  the  Herbivores. 

There  are  others  which  live  on  the  dead  or  decaying-  plant,  on  dead 
leaves,  on  rotting  fruits,  on  dry  timber.  Any  vegetable  tissue  that  is  no 
longer  alive  and  growing  furnishes  food  to  this  division.  We  may 
include  with  them  the  feeders  on  decaying  animal  tissue,  such  as  the  dung 
feeders,  the  carrion  beetles,  the  corpse  buriers.  We  may  term  them  all 
Scavengers,  since  they,  with  the  bacteria  and  fungi,  cleanse  the  earth 
of  its  rubbish  and  convert  it  into  good  plant-food  again.  They  also 
form  a  large  division,  not  less  important  but  far  less  visible  to  us,  work- 
ing in  the  dark  and  in  hidden  places. 

As  the  plant  world  furnishes  food  for  so  many  insects,  so  also  these 
insects  in  turn  are  fed  on  by  others,  and  we  find  a  very  large  division 
which  get  their  food  from  the  herbivorous  and  scaveng'ing  insects  or  from 
each  other.  These  work  in  two  ways,  by  preying  upon  insects  and  eating 
them  bodily,  as  a  tiger  eats  a  cow,  or  by  living  within  their  bodies 
parasitically,  as  a  tapeworm  lives  in  a  horse.  The  former,  the  Predators, 
we  see  daily  at  work  and  we  may  compare  them  with  the  many  insec- 
tivorous birds.  The  latter,  the  Parasites  (Ichneumons  and  flies),  are  not 
less  numerous  and  abundant ;  their  larvae  live  in  the  insect,  absorbing  the 
food  laid  up  by  the  host  and  gradually  killing  it.  The  two  groups 
together  check  the  immense  increase  of  insect  life  and  form  the  third 
great  division. 

There  are  also  a  small  number  of  insects  that  live  parasitically  in  or 
on  warm-blooded  animals.  They  feed  on  the  blood  of  man,  cattle,  wild 
beasts,  birds  and  other  animals,  or  live  parasitically  within  their  bodies. 
They  form  a  small  division. 

There  are  lastly  the  insects  which  have  found  that  man  offers  many 
comfortable  homes  in  his  houses  and  buildings ;  they  live  upon  grain, 
flour,  drugs,  all  manner  of  produce  and  household  stores  ;  they  inhabit  our 
houses,  deriving  a  precarious  existence  from  what  they  can  pick  up. 
These  are  the  household  pests  ;  they  have  been  carried  in  ships  to  all  parts 
of  the  world  and  established  themselves  wherever  man  is.  This  division 
is  not  large  or  very  important  but  an  aberrant  and  distinct  oli'shoot  from 
the  great  scavenger  class  mentioned  above. 

We  have  now  included  practically  every  insect  in  our  divisions,  and 
if  we  subdivide  them,  almost  every  species  whose  habits  are  known  would 
flt  in.  We  see  the  part  each  plays  in  the  great  cycle  of  life.  The  herbivores 
feed  on  the  plants,  which  build  up  organic  matter  from  the  soil  and  air 
under  the  influence  of  the  sun.     These  herbivores  build  up  the  plant  tissue 


FOOD.  13 

into  more  eomplox  ovoj-anic  eomponnds  and  in  turn  supply  food  for  otliors. 
The  scavengers  feed  on  the  decaying  plant  life  and  animal  Me,  clearino- 
the  earth  of  deeayino'  refuse,  making-  it  clean  and  sweet ;  eventually  they 
die  and  the  Avhole  mass  of  organic  material  breaks  up  into  the  compounds 
available  for  plant  life.  The  parasites  and  predators  feed  upon  the  living 
insects,  checking  the  increase  of  both  herbivore  and  scavenger,  so  that 
the  destruction  of  living  plant  life  by  herbivores  can  then  never  go 
beyond  a  certain  point,  the  balance  thus  being  maintained.  We  are  in 
this  volume  mainly  concerned  with  the  herbivorous  insects,  those  which 
feed  upon  the  living  plant.  They  are  largely  injurious  to  man,  though 
also  beneficial.  We  cannot  neglect  the  parasites  and  predators,  for  in 
actual  work  we  meet  them  at  every  turn  ;  the  part  they  play  is  not  very 
evident,  but  the  practical  study  of  pests  requires  that  every  student  of 
agriculture  should  be  familiar  with  them  and  recognise  them  almost  at  a 
glance.  The  scavengers  are  not  of  direct  importance  and  we  see  them 
but  little  ;  grain  aud  household  pests  are  of  direct  importance  to  man  as 
also  the  insects  parasitic  upon  cattle  and  warm-blooded  animals. 


Food  Plants. 

Caterpillars  and  other  herbivorous  insects  may  have  one,  a  few,  or 
many  plants  on  which  they  can  feed  and  thrive.  Evidently  an  insect 
that  can  live  on  a  variety  of  plants  has  an  advantage  over  one  that  lives 
only  on  one  or  a  few,  and  injurious  insects  are  largely  those  which  have 
a  great  range  of  food-plants,  enabling  them  to  spread  widely,  to  increase 
abundantly,  and  to  find  food  when  crops  are  not  available  for  them.  The 
list  of  injurious  insects  is  nearly  synonymous  with  the  list  of  insects 
having  many  food-plants. 

In  general,  insects  feed  upon  one  or  more  closely  allied  plants ;  thus 
cotton  pests  are  found  also  on  hUnda  and  other  species  of  Hibiscus,  cane 
pests  on  maize  and  sorghum,  and  so  forth.  In  other  cases  they  feed  on 
plants  which  bear  similar  fruits ;  an  insect  that  eats  tlie  oily  seeds  of 
cotton  will  perhaps  feed  on  the  oily  seeds  of  other  plants  not  closely  allied 
to  cotton. 

The  food-plants  of  some  species,  e.g.,  the  gram  caterpillar,  are  to  be 
numbered  in  scores.  The  food-plants  of  others  are  few,  and  there  are 
insects,  for  instance,  which  can  feed  on  certain  varieties  of  cotton  aud 
not  on  others.  The  composition  of  the  tissues  of  the  plant  probably 
determines  its  suitability  to  insects,  and  some  plants  appear  to  have  no 
pests.  Plants  protect  themselves  in  various  ways,  but  insects  in  their 
turn  seem  equally  to  accustom  themselves  to  the  oils,  alkaloids,  hairs. 


14  INSECTS  :    THEIR    STRUCTURE   AND    FOOD. 

thorns,  etc.,  with  which  plants  have  tried  to  render  themselves  safe. 
Modern  science  has  not  yet  discovered  any  method  of  altering  the  com- 
position of  plant  sap  so  as  to  render  it  distasteful  or  poisonous  to  insects. 
When  this  subject  has  been  mastered,  we  shall  be  in  a  position  to  deal 
more  siicccssfnlly  with  insects  by  purely  preventive  methods. 


CHAPTER  II. 


LIFE  HISTORY  AND  HABITS. 

INSECTS  pass  thvoug-h  various  chaiig-os  diirino-  thoir  lives,  ehan^^es  of 
form,  habits,  structure  and  the  like ;  these  transformations  are  in 
many  cases  very  g-reat,  being-  the  most  striking-  characteristics  of  the  life 
history  of  insects.  Whilst  the  life  history  is  essentially  the  same  through- 
out larg-e  groups  of  insects,  it  is  not  exactly  the  same  in  any  two  species. 
We  can  g-ive  here  only  a  very  brief  outline,  but  fuller  details  will  be  found 
in  the  later  sections. 

Insects  are  hatched  from  eggs,  which,  though  smaller  and  different 
in  appearance,  are  essentially  similar  to  those  of  birds.  These  eggs  arc 
not  cared  for  by  the  parent  insect,  but  are  laid  in  such  a  position  that  the 
young  when  they  emerge  will  find  suitable  food. 

From  the  eggs  hatch  out  tiny  insects  which  are  usually  able  to  feed 
almost  at  once  and  begin  their  active  life  without  delay.  They  feed 
voraciously  and  rapidly  grow  larger.  Their  cliitinous  skin  will,  however, 
not  stretch  and  permits  of  growth  only  to  a  certain  limit ;  when  this  is 
reached,  a  new  soft  skin  is  formed  under  the  old  one ;  the  latter  splits 
so  that  the  insect  crawls  out  with  only  the  new  soft  skin  ;  the  insect  at 
once  expands,  the  new  skin  hardens  with  the  result  that  our  little  insect 
is  suddenly  twice  its   previous  size  and   perhaps 

very   different  in  appearance.     Growth    again 

continues  until  the  insect  is  too  large  for   the 

second  skin,  when  the  process  is  repeated  and 

a  fresh  moult  undergone.     The  skin  is  thus 

shed  periodically   until   the   insect    attains   its 

full  size  and  mature  form.     At  every  moult 

the  appearance  of  the  insect  changes ;  it  may 

be    a   minute   change   in  appearance   with   a 

considerable  change  in  size,  or  it  may  be  a  com- 
plete change  of  form,   with  change  of  habits 

and  structure.     The  number  of  moults  varies 

from  two  to  twenty  or  more,  but  is  generally 

about  five  to  seven. 

These   changes   form  the   essential  part  of 

the    life  history   of    insects.       We    can    now 

examine  in  detail  the  nature  of  the  changes  ^^*^'  ^^' 

J  •      ii  J  c  •  ,  £lo(JS  of  a  Butterfly;  natural 

undergone  m  the  great  groups  of  msects.  Ze  on  a  leaf,  and  enlarged. 


16 


LIFE   HISTOUY   AND   HABITS. 


If  we  patch  a  female  butterflj^,  for  instanee,  ilie  very  enmmnn  one  that 
is  fio-ni-od  (fio".  24)  and  keep  it  in  a  suitable  eage,  it  Avill  lay  eowp.  These 
eg-o-s  are  shown  in  figs.  19-30  much  mag-nified,  and  in  another  fionirc 
(fio-.  18)  are  showai  the  eggs  of  another  butterfly  both  mao-nified  and 
natural  size.  The  eggs  are  small  white  seed-like  things  and  laid  singly 
on  the  leaves  of  a  plant.  If  we  keep  these  eggs,  they  will  presently 
hatch  into  caterpillars  (fig.  21)  ;  these  are  somewhat  worm-like  in  appear- 
ance,   with    legs  and  sucker-feet,    totally  different    from   the  butterfly 


Fig.  19.  Fig.  20. 

Butterfy  Ff/g.     {Magnified.)  Fgg  after  Caterpillar  leaves  it.     {Magnified.) 

in  habits  and  structure.  These  caterpillars  eat  the  leaves  of  the 
plant  and  moult  as  they  grow  larger;  at  each  moult  the  colour 
chang-es  very  slightly,  and  the  caterpillar  comes  out  much  larger.  There 
are  five  such  moults,  and  at  the  end  of  twelve  or  fifteen  days  the  caterpillar 
has  attained  to  its  full  size   (fig.  22).     It  now  ceases  to  feed,  becomes 


im 

mm'' 

wWff 

■wi  = 

'H\ 

Fig.  21. 
Young  Caterpillar. 


Fig.  22. 
Fiill  grown  Caterjrillar. 


uneasy  ;  it  is  preparing  for  another  moult.  To  do  this  it  fastens  a  small 
pad  of  silk  at  some  point  on  the  leaf  of  the  plant,  and  fixing'  the  hooks 
of  its  tail  sucker-feet  in  the  silk,  hangs  itself  head  downwards  from  the 
pad  of  silk.  The  skin  bursts  and  is  thrown  off  and  the  insect  is  seen 
hanging"  from  the  leaf.  It  is  now  completely  changed  in  appearance  and 
is  called  a  chrysalis  ;'  it  is  a  rounded,  green  object,  with  pretty  gold 
markings  (fig.  23)  ;  there  are  no  limbs,  no  mouth,  no  eyes  ;  spiracles  alone 
can  be  seen.     This  curious  creature  hangs  motionless  from  the  plant  for 

*  Chrysalis];  plural  chrysalides. 


LIFE   OF   A    BUTTERFLY. 


17 


six  days,  taking  no  food  and  appearing-  to  be  asleep.     At  the  end  of  six 

days,  the  outer  skin  bursts,  and  a  larg-e  insect  comes  out.     This  walks 

feebly   about   for   a   few   minutes   whilst   its   large   wing-s   expand  and 

spread  out;  these   wing-s  become 

firm   and   stiff  and    we   see  that 

it    is    the    butterfly    again    (fig. 

24)     similar     to     the     one    first 

caught.      This  butterfly    will  fly 

away,      mate      and      again     lay 

eggs,  which  will  again  hatch  to 

caterpillars,   the  cycle  beginning 

again. 

This  is  a  very  short  descrip- 
tion of  what  occurs  in  the  life 
of     this    butterfly    and    similar 


Fig  23. 

Chrysalis  of  the  Butterfly. 

changes  take  place  in  the  life  of  every  butterfly.     We   see   in  it  four 
stages— the  ^g^,  the  caterpillar,  the  chrysalis,  and  the  butterfly. 

During  the  q^^  stage  the  caterpillar  is  formed  from  the  germ; 
the  caterpillar  feeds,  grows  larger  and  moults;  at  each  moult  the^re  are 
only  small  changes,  and  during  the  growth  in  size,  covering  five  moults, 


Fig.  24. 
Butterfly. 

the   insect   changes   but  little;  its  whole   business  is   feeding,  growing 
larger,  and  lading  up  a  store  of  fat.     When  the  caterpillar  is  fulfgrown, 

P 


18 


LIFE   HISTOEY   AND    HABITS. 


tlie  big  cliang'e  takes  jalace ;  for  this  it  jireiDares  by  hauging"  itself  in  a 
convenient  place,  out  of  the  way  of  enemies,  etc.,  and  becomes  the 
chrysalis.  During  this  period  an  internal  transformation  takes  place 
and  the  tissues  of  the  caterpillar  build  up  the  butterfly.  There  is  no 
process  akin  to  this  in  any  domestic  animal  with  which  we  are  familiar ; 
every  part  of  the  caterpillar  is  built  up  anew ;  the  internal  organs  are 
remodelled;  wings  are  formed;  long  legs  take  the  place  of  the  short 
caterpillar  legs ;  the  biting  jaws  of  the  caterpillar  have  been  thrown  off 
and  the  long  tubular  proboscis  of  the  butterfly  is  formed ;  new  compound 
eyes  are  formed ;  new  sense  organs  appear.  Further,  the  entire  repro- 
ductive system  of  the  butterfly  is  built  up  and  formed.  Only  the 
beginnings  of  a  reproductive  system  are  to  be  found  in  the  caterpillar,  but' 
a  more  or  less  complete  and  complex  system  of  rej)roductive  organs,  male 
or  female,  is  formed  during  this  stage.  When,  at  the  end  of  six  days, 
the  butterfly  within  is  fully  formed,  it  emerges;  the  skin  is  soft,  the 
wings  soft  and  folded  up;  in  a  short  time  the  wings  expand,  become 
hard  and  dry ;  the  body  takes  on  firmness,  the  legs  become  stiff,  and  the 
butterfly  is  ready  to  fly  away,  with  new  senses,  new  instincts,  to  suck 
the  nectar  from  the  flowers,  to  find  its  mate  and  to  flutter  gaily  in  the 
sunshine — a  change  as  great  as  we  can  imagine  from  the  crawling 
caterpillar  that  hung  itself  up  six  days  before. 

The  life  of  all  insects  is  not  exactly  similar  to  that  of  the  butterfly, 
and  we  may  take  the  life  of  a  grasshopper  as  an  example  of  what  changes 
take  place  in  some  other  insects. 


K'^^W^ 

> 

1 

k.  ^^ 

W 

r  \'W 

^m 

w^ 

•^ 

m'' 

y 

l'-# 

J 

LP^ 

^4 

^■^ 

Fig.  25. 
Iig(j  mass  detiic//('i/, 


Fig.  20. 
lEf/ff  'jiiass  in  ff round. 


LIFK    01'    A    GlfASSIlOlTEl!. 


19 


The  female  grasshopper  lays  amass  oP  eg-g-s  (%s.  25,  20)  in  the  ground 
and  shortly  after  dies.  These 
cg'gB  lie  in  the  ground  for  some 
weeks  and  presently  each  splits 
and  a  young-  insect  comes  out. 
This  young"  insect  is  very  small, 
about  twice  the  length  of  the 
egg's,  and  very  active.  The 
general  form  is  like  that  of  the 
parent ;  there  are  the  long  legs, 
the  hind  pair  very  large  (fig,  27), 
and  the  head  like  that  of  the 
grasshopper  with  similar  antennte  and  jaws.  But  there  are  no  wings  and 
the  little  insect  can  only  leap.  It  is  also  quite  distinct  in  colour.  It  feeds 
upon  green  plants  just  like  its  parents  did  and  grows  larger.  Moults  take 
place  as  in  the  caterpillar,  and  at  every  moult  the  insect  comes  out  larger 
and  somewhat  differently  coloured.  At  the  fourth  moult  (fig.  28)  two 
lobes  appear  at  the  upper  side  of  the  body,  on  the  second  and  third 
segments  of  the  thorax,  above  the  second  and  third  pair  of  legs.  At  each 
later  moult  these  grow  larger  until  with  the  sixth  or  seventh,  they  take 


Fig.  27. 
Yonnrf  Insect,  one  daij  old. 

iimes.) 


(Mar/nifled  five 


Fig.  28. 
llalf-groivn  Insect.     (Mar/ n ijied  twice.) 

the  form  of  the  large  perfect  wings.  Our  grasshopper  (fig.  29)  is  now 
full  grown  and  moults  no  more.  It  has  perfect  wings,  a  fully 
developed  reprodiTctive  system,  and  will  presently  mate,  lay  eggs  and  die. 
This  life  history  is  a  great  contrast  to  that  of  the  butterfly;  the 
young  is  like  the  parent  in  general  form,  feeds  in  the  same  manner  and 


ao 


LIFE    HISTORY    AND    HABITS. 


lives  a  similar  life.  At  each  moult  it  grows  larger  and  gradually  changes, 
almost  imperceptibly,  till  it  is  full  grown.  There  is  no  caterpillar,  no 
chri/salis  ;  there  are  no  sudden  changes  at  any  moults  ;  the  wings  grow 
slowly ;  the  reproductive  system  is  developed  gradually ;  there  is  no 
period  of  rest,  and  the  insect  feeds  at  every  stage  of  its  life.  We  may 
concisely  state  that  whilst  the  grasshopper  develops  gradually,  the 
butterfly  does  so  suddenly.  The  sudden  change  from  caterpillar  to  chry- 
salis, and  chrysalis  to  butterfly,  is  one  distinguishing  feature ;  this  is 
called  the  mttamorpliosis,  and  all  insects  which  pass  through  these 
changes  are  said  to  have  a  '^metamorphosis.'^  It  is  a  convenient  word 
which  expresses  the  facts  that  (1)  the  young  insect  is  totally  unlike  the 
mature  insect ;  (2)  between  the  two  is  the  resting  stage  similar  to  that  we 
call  chrysalis.  We  might  divide  all  insects  into  two  groups,  those  which 
are  caterpillars  and  chrysalides  before  they  become  butterflies,  and  those 
which  change  gradually  and  slowly  till  they  become  grasshoppers. 
The  first  have  a  metamorphosis,  the  second  have  none.  Speaking  gen- 
erally, all  insects  belong  to  one  group  or  the  other.     They  either  have 


€tiX> 


Fig.  29. 
The  'perfect  Insect. 

metamorphosis  and  pass  through  four  stages,  viz.,  (1)  the  q^^  ;  (2)  a 
stage  like  the  caterpillar  (called  larva) ;  (3)  a  stage  like  the  chrysalis 
(called  p2cpa)  ;  (4)  the  mature  stage  like  the  butterfly  (called  imago) ;  or 
they  have  no  such  distinct  stages  but  commence  as  eggs,  pass  through 
a  series  of  gradual  changes  during  wdiich  we  may  call  the  insect  a  nijm'pli, 
to  the  perfect  insect,  called  the  imago} 

It  will  be  seen  that  we  have  here  a  character  that  sharply  divides  all 
insects  into  two  groups.     There  are  some  insects  which  have  a  partial 

^  Larva,  plural  larvae  ;  jpupa,  plural  pupa  ;  imago,  plura]  imagineft ;  nymfh,  plural 
nymphs,  '      '  ' 


MK'rA]iioiil>Hclsisi. 


iii 


Fig.  30. 
A  wingless  mature  CocJcroach. 


metamorphosis  aud  which  are  really  intermediate  between  these  two 
groups;  but  they  are  not  common  aud  Ave  arc  unlikely  to  meet  with 
them.  We  shall  find  large  and  distinct  groups  of  insects  which  have  a 
metamorphosis,  and  equally  large  and 
distinct  groups  which  have  none  ; 
every  student  shoidd  know  at  once 
whether  an  insect  has  or  lias  not  :i 
metamorphosis. 

Before  proceeding  to  the  next  sec- 
tion, we  may  draw  attention  to  a 
few  points. 

All  perfect  insects,  i.e.,  ima- 
gines, have  wing's,  or  should  have  ; 
there  are  many  exceptions  to  the 
rule  and  in  many  insects  the  wings 
are  not  fully  developed.  This  is  more  common  in  insects  which  have  no 
metamorphosis  than  in  those  which  pass  through  the  pupa  stage. 

Such  insects  which  look  immature  can  be  known  as  mature  if  seen 
coupling.     None  but  imagines,  i.e.,  perfect  insects,  can  couple  or  reproduce. 

On  the  other  hand,  any  insect  with  fully  developed  wings,  i.e.,  with 
wings  with  which  it  can  fly,  is  an  imago  and  will  not  grow  any  more.  A 
small  flying  grasshopper  cannot  be  a  young  locust  or  become  anything 
else.  A  small  beetle  cannot  grow  into  a  large  beetle.  Whatever  its  size, 
a  winged  insect  is  full  g*rown  and  will  not  do  more  than  lay  eggs.  This 
is  an  absolutely  invariable  rule. 

In  later  paragraphs,  the  life  history  is  stated  in  greater  detail  and 
some  of  the  many  exceptions  to  general  rules  are  discussed.  In  entomo- 
logy, as  in  all  other  branches  of  biology,  the  general  rules  are  abundantly 
proved  by  their  exceptions.  There  are  very  few  general  statements  that 
can  be  made  to  which  there  are  not  many  exceptions.  We  can  say 
generally  that  all  insects  are  hatched  from  eggs,  but  there  are  very 
numerous  exceptions  ;  equally  we  can  say  generally  that  mature  insects, 
like  other  creatures',  are  of  two  sexes  and  that  the  process  of  reproduction 
is  dependent  upon  both  sexes ;  even  this  statement  is  not  true  of  all  insects. 
It  is  necessary  to  guard  against  hard-and-fast  rules  and  generalities 
in  dealing  with  infects  ;  they  are  valuable  as  aids  to  memory  and  the 
imagination,  inevitable  in  class  rooms  and  books,  but  they  must  be  carefully 
used  outside  the  class  room.  Nature  has  no  cast-iron  rules,  and  the  more 
we  study  nature  the  more  we  find  an  infinite  variety  that  laughs  at  our 
generalisations.  One  group  shades  into  another ;  the  habits  of  one  class 
are  linked  to  those  of  another  by  insensible  gradations  ;  no  tAvo  species 


a2 


LIFE   HISTORt    AND    HABITS. 


are  alike  iu  form  or  habits,  so  that  we  must  have  a  c-lear  coiiceptioii  that 
we  are  not  in  a  world  o£  clear-ent  definitions  and  distinctions  but  in  one 
whose  first  charm  lies  in  its  infinite  variety. 


Eggs. 

Insects  are  not  produced  spontaneously  from  plants  or  from  dirt,  but 
arise  from  eg-g-s  laid  by  the  parent  insect,  or,  in  rare  cases,  are  born  alive. 
No  case  is  known  of  insects  having  been  produced  in  any  other  way,  and 
in  tracing  the  life  of  an  insect  we  may  commence  from  the  time  the  parent 
lays  the  egg.  Insects  often  appear  suddenly  in  great  numbers,  and  ignor- 
ant cultivators  believe  that  they  have  fallen  from  the  sky  or  are  due  to 
a  change  of  weather  or  some  similar  cause.  The  appearance  of  an  insect 
in  small  or  large  numbers  is  not  a  supernatural  phenomenon  and  can  only 
be  caused  by  the  parent  insect  having  laid  eggs  or  j)roduced  living  young 
in  or  near  that  spot  at  some  earlier  time  ;  the  eggs  may  not  have  been 
seen  and  may  have  been  there  for  several  months,  but  in  every  case  if  Ave 
could  go  back  far  enough  we  could  trace  them  to  the  parent  insects.. 
Eeproductiou  in  the  insect  world  is  a  process  similar  to  that  of  the  higher 
animals  and  no  more  mysterious;  it  depends  upon  simple  causes  which 
are  fully  capable  of  investigation  and  differs  but  little  from  those  which 
bring  about  reproduction  and  multiplication  in  other  living  creatures. 

In  almost  all  cases,  the  eggs  are  produced  after  the  mating  of  the 
male  and  female  insects  ;  there  are  a  few  groups  of  insects  in  which 
males  occur  rarely  or  not  at  all  ;  the  females  then  produce  eggs  or  Hving 
young  without  the  co-operation  of  the  males,  but  this  is  confined  to  a 
small  number  of  insects  and  in  them  occurs  regularly.     If  a  bred  female 

moth  is  kej)t  alone  in-  a  cage,  she 
may  lay  eggs,  but  they  are  imperfect 
and  do  not  hatch ;  an  aphis,  on  the 
other  hand,  may  produce  eggs  or. 
Hvin^  young  without  any  male  being 
present,  many  successive  genera- 
tions being  thus  produced  without 
the  intervention  of  any  male.  In 
some  groups,  insects  are  born  h,livc. 
In  the  ajj hides  this  is  the  normal 
process  during  part  of  the  year,  no 
eggs  being  formed,  but  the  virgin  female  producing  living  young. 

In  some  flies,  the  female  carries  the  fertilised  eggs  within  her  body 
awaiting  a  suitable  opportunity  to  lay  tliem  on  sufficiently  decayed  matter^ 


Fig.  31. 
Coclroach  T.gg  case.     {Mar/vified.) 


EGGS. 


23 


and  these  eggs  often  hatch  before  they  are  laid,  the  Hy  then  depositin"- 
living-  maggots.  These  phenomena  oeeur  rarely  in  other  insects,  being 
exceptions  to  the  almost  universal  rule  that  insects  hatch  from  eggs. 

Eggs  are  usually  laid  where  the  young  will  find  abundant  food  and 
are  then  abandoned  hy  the  parent.  Exceptionally  the  parent  cares  for 
and  watches  over  the  eggs  ;  this  is  the  case  also  in  social  insects,  but  the 
eggs  are  then  more  usually  looked  after  by  special  individuals  and  not  by 
the  parent.  In  most  cases  the  parent  dies  soon  after  the  completion  of 
egg-laying  and  the  young  that  hatch  live  an  independent  life  from  the 
moment  they  emerge.  The  beautiful  instincts  of  the  digger  wasps  are 
perhaps  the  best  instances  of  maternal  care  for  the  young  (see  page  271). 

The  number  of  eggs  produced  by  the  individuals  of  any  one  species 
is  usually  fairly  uniform,  but  varies  very  much  in  different  species.  The 
large  Six-spotted  Ground  Beetle  (fig.  344)  produces  one  large  egg  at  a  time 
and  produces  only  a  few  in  its  life ;  other  beetles  produce  them  singly  and 
generally  lay  only  a  comparatively  small  number,  but  the  tortoise  beetles. 


Fig.  32. 
"Eg;]  case  and  youvg  of  Mantis,  llie  latter  marjuljied. 

for  instance,  produce  many  and  may  lay  them  in  beautiful  egg  cases. 
Generally  beetles'  eggs  are  laid  singly  and  are  hard  to  find.    Moths  lay  many 


u 


LIFE    HISTOE"X    AND    HABITS. 


eggs,  usually  upwards  of  one  hundred,  in  clusters  or  masses.  Butterflies  lay 
them  singly  and  in  great  number.  The  queen -bee  produces  a  vast  number 
of  eggs,  laying  them  singly  in  the  special  cells.  The  locusts  and  larger 
grasshoppers  lay  about  one  hundred  eggs  ;  the  smaller  grasshoppers 
some  fifty  or  so.     The  Neuroptera  lay  many  eggs,  as  do  the  Ort/iopfera.^ 

It  is  probably  correct  to  say  that  insects  which  are  exposed  to 
enemies  lay  many  ei^gs  to  allow  for  the  inevitable  destruction  of  the 
majority  of  the  young,  whilst  "  safe  forms,''"'  which  live  in  hiding  or  are 
exceptionally  well  protected  from  dangers  and  from  enemies,  lay  a  few. 
The  form  of  the  eggs  varies  very  much  in  different  families.  Cock- 
roaches lay  eggs  (fig.  31)  in  a  single  case  of  peculiar  form,  as  do  the 
mantis  or  praying  insects  (fig.  32).  Stick  insects  drop,  one  at  a  time, 
peculiar  seed-like  eggs  with  lids.  Locusts  and  grasshoppers  lay  a  mass 
of  long  oval  eggs  in  the  ground  and  green  grasshoppers  lay  them  in  the 
tissues  of  plants.  The  eggs  of  the 
Lacewing  (fig.  332,  page  27-i)  resemble 
grains  of  rice  and  are  set  each  on  a 
stalk ;  many  other  Neuroptera  lay  masses 
of  eggs  in  fresh  water.  The  eggs  of 
H^mennptera  are  small,  soft,  white 
bodies,  sometimes  stalked.  Butterflies 
lay  round  seed-like  eggs,  beautifully 
ribbed ;  moths  lay  similar  round  or  flat 
eggs  usually  ornamented  or  marked. 
The  eggs  of  the  common  flies  are  cigar- 
shaped,  deposited  singly  or  in  masses. 
Bugs  often  lay  neat  cylindrical  eggs  with 
lids,  depositing  them  in  batches ;  the 
eggs  of  the  Red  Cotton  Bug  are  round 
and  yellow,  laid  in  the  soil,  whilst  those 
of  the  Dusky  Bug  are  cigar-shaped  and 
laid  in  the  lint  of  the  cotton.  With  such 
infinite  variety,  general  statements  can  be  accepted  only  with  great  caution. 

The  period  during  which  the  egg  remains  before  hatching  varies 
immensely  according  to  species,  climatic  conditions  and  other  factors. 
The  eggs  of  butterflies  hatch  in  a  few  days,  as  do  those  of  mosquitdes ; 
the  eggs  of  moths  hatch  very  quickly  in  Avarm  damp  weather,  but  dry 
cold    will   delay   them.     Many   insects'  eggs   remain   from    October   or 


Fig.  33. 
The  eyys  of  a  Plant  Bug  on  a  leaf. 


^  It  is  necessary  to  use  srienlific  words  to  designute  grcups  for  which  tVere  Hie  no 
English  equivalents.  Ti.e  reader  will  tiud  the  exphiuation  of  lhe^e  words  on  pages  62— 
54.H:H.  Al.-L.j  ^  ^ 


November  to  the  following  rains.  The  Rice  Grasshopper^^  i^gs 
normally  stay  in  the  ground  for  eight  months,  but  will  hatch  earlier  if 
kept  wet.  The  degree  of  moisture  and  heat  have  a  great  influence  on 
this  period,  and  little  is  yet  known  of  the  influence  of  climatic  changes  on 
insect  eggs  in  India. 

Larval  Life. 

When  the  larva  is  formed  inside,  the  egg  breaks  and  allows  it  to 
emerge.  There  are  special  devices  for  securing  the  rupture  of  the  egg  at 
the  right  time,  which  deserve  study.  Many  caterpillars  at  once  eat  the 
eo-o-shell  and  then  start  feeding  on  their  food-plant.  As  a  rule,  larviB 
develop  rapidly  with  a  plentiful  supply  of  food  and  proper  conditions. 
The  temperature  and  degree  of  moisture  play  a  great  part  in  the  growth 
of  the  young  larvae.  Feeding  is  the  sole  important  business,  and  growth 
is  rapid.  Moults  occur  as  necessary;  caterpillars  shed  their  skins  five 
times  as  a  rule ;  grasshoppers  do  so  five,  six  or  seven  times ;  the  silkworm 
does  so  four  times.  Many  bugs  do  so  five  times,  though  the  Mealy  Bugs 
and  Scale  Insects  have  only  two  cr  three  moults.  Some  aquatic  insects 
moult  as  many  as  twenty  times. 

Though  the  process  of  moulting  is  necessary  to  allow  of  continued 
growth,  it  has  also  a  physiological  reason.  The  chitinous  matter  thrown  off 
is  nitrogenous  and  it  is  probable  that  the  nitrogenous  waste  products  of  the 
body  are  eliminated  in  this  manner ;  insects  have  no  organs  which  correspond 
directly  to  the  kidneys  of  the  higher  animals,  and  a  part,  if  not  all,  of  the 
nitrogenous  waste  matter  is  excreted  and  periodically  shed  as  chitiu. 

With  each  moult  the  form  and  colour  change  slightly  or  greatly.  It 
must  not  be  taken  for  granted  that  the  number  of  evident  colom-  clianges 
and  the  number  of  moults  are  synonymous.  W^e  cannot,  for  instance, 
collect  a  great  number  of  the  young  of  a  grasshopper,  sort  them  into 
groups  according  to  size  and  colour,  and  then  say  that  each  group  is  the 
result  of  one  moult ;  the  changes  at  one  moult  may  be  very  slight,  though 
far  more  striking  at  every  other  moult.  Moulting  is  not  such  a  regular 
automatic  process  that  all  individuals  of  a  species  have  actually  the  same 
number,  and  it  has  been  found  that  grasshoppers  from  the  same  batch  of 
eggs  take  six,  seven  or  eight  moults  to  attain  maturity. 

Larval  life  may  be  very  short  or  very  long,  depending*  upon  the 
habits  of  the  insect,  as  well  as  on  climatic  and  other  conditions.  Generally 
speaking,  development  is  more  rapid  in  hot  weather,  slower  in  cold.  There 
is  an  optimum  temperature,  the  temperature  at  which  development  is 
most  natural,  which  climatic  conditions  retard  or  hasten.  There  is  also  an 
optimum  degree  of  humidity,  varying  for  each  species.  A  rise  of  tem- 
perature above  a  certain  point  or  a  fall  below  a  certain  point  may  almost 


26 


Life  histoe^  and  habi'is. 


or  entirely  suspend  vital  activities  temporarily,  and  this  is   determined  by 
the  circumstances  imder  which  each  species  lives. 

General  statements  are  nearly  impossible  as  they  are  certain  to  convey 
false  ideas.  Throug-hout  it  must  be  remembered  that  every  species  of  in- 
sects is  distinct  from  every  other  species  in  habits,  and  that  every  species 
has  as  much  individuahty  as  each  human  being*,  no  two  species  living 


Fig.  34. 
Cicada,  slightlt/  enlarged. 

under  identical   conditions.     We  can   go  much  further  than  this,  since 
even  species  are  not  well  marked  and  shade  imperceptibly  into  one  another, 


:^^t 


Fig.  35. 

A  Hairy  Caier^iUar,  and  ils  pupa  icith  the  cocoon  formed  of  silk  and  hairs  made  ly 
the  caterpillar  lefore  it  lecomes  a  pvpa. 


PV?2P,. 


il 


Fig.  36. 
Weevil,  and  the  case  from  wl/ich  it  emer<jes. 


Fig.  37. 

The  Flanlaiii  Weevil,  and  the  case  of  iwisled 

Jibres  from  n'/iich  it  emerf/es. 


but  if  we  are  to  have  clear 
conceptions  of  insects'  aeti- 
vitiesj  we  must  think  of 
each  species  as  distinct,  so 
distinct  that  even  we  can 
see  the  differences. 

Subject  to  this,  we  may 
say  that  cold  retards  the 
development  and  activities 
of  insects;  even  the  cold  of 
the  plains  sends  many  in- 
sects into  a  torpid  condition, 
this  hibernation  lasting  for 
periods  that  vary  accord- 
ing- to  the  lowness  of  the 
temperature.  Equally,  lack  of 
food,  dry  air,  and  intense  heat, 
compel  the  majority  of  insects 
to  be  dormant  in  some  form  for 
some  months  of  the  year.  This 
is  dealt  with  subsequently.  The 
periods  of  larval  life  may  be  a 
few  days  as  in  many  fly  maggots, 
a  few  weeks  as  in  most  moths, 
beetles,  etc.,  or  a  few  or  many 
months,  as  in  many  beetles.  The 
Cicadas  probably  live  far  longer 
as  nymphs,  one  American  species 
living  seventeen  years  under- 
iiround     before      becoming    an 


Pupal    Life. 

The  pupa  being  inactive  and 
helpless  is  usually  concealed  or 
protected  from  enemies.  In 
Hymeiioptera  it  is  commonly 
encased  in  a  silken  covering,  in 
a  cell,  a  nest,  or  in  tlie  ground. 
In  Coleoptera  a  silken  cocoon  is 
never  formed,  thougli  approaches 


^8 


tli-E   HISTORY    AND    ttABlTS. 


to  it  are  known ;  the  pupa  is  commonly  in  the  ground  in  an  earthen  cell, 
or  in  the  burrow  o£  the  larva  or  in  a  tough  case  on  a  plant.     Many  have 
naked  pups  fastened  to  plants.     The  cases  they  make  are  of  twisted  fibres 
(fig.  37)  as  in  the  Palm  Weevil  (fig.  2-i7),   of   excrement   (fig.  36)   as  in 
some  leaf  beetles  and  weevils,  or  of  secretion  produced  by  the  larva  (some 
weevils).      The  butterflies  have  suspended  pupse,  fastened  to  plants,  often 
of  peculiar  form  with  resemblances  to  torn  leaves,  etc.     Moth  pupse  are 
usually  in  cocoons  formed  of  silk  alone   (fig.  39)   or  with  hairs  (fig.  35) 
or     are    found    in     the 
ground,    on    plants,    in 
the  larval    burrows,  etc. 
The  silk    of    commerce 
is    produced    from    the 
cocoons  of  various  moths, 
and    almost     all    cater- 
pillars can    produce  silk 
throughout    their  larval 
life,  using  it  for  a  variety 
of  purposes.     The    pupa 
of  Dipt  era  is  to  be  found 
in    the   habitat    of    the 
larva,  without  covering  as  a  rule.     Insects  dis^Dlay  great  ingenuity  in  the 
devices  they  adopt  for  the  protection  or  covering  of  the  pupa.     The  pupal 
period  is  commonly  short,  a  few  days  in  flies,  a  week  to  ten  days  in  many 
butterflies  and  moths  (unless  hibernating),  about  the  same  in  the  known 
HymenojHera  and  in  some   Coleoptera.     It  is 
however  much  prolonged  in  some  Coleoptera 
and  may  be  very  long  in  all  groups  if  hiberna- 
tion is  taking  place  in  the  pupa,  as  it  often  does. 

In  some  Coleoptera,  the  imago  emerges 
from  the  pupa  and  undergoes  a  further 
resting  period  before  leaving  its  hiding  place. 

We  may  here  mention  the  flies  which 
pass  through  no  larval  period,  but  are  pro- 
duced by  the  parent  as  full  grown  larvae 
which  at  once  pupate.  The  best  known  of 
these  are  the  Horse  and  Cattle  Flies  (fig.  320, 
page  265)  which  live  upon  the  blood  of  birds 
and  mammals.  This  abnormal  life  history 
is  possibly  an  adaptation  to  the  semi-parasitic 
life  of  the  imago. 


Fig.  38. 

Butterfly  Chrysalis,  shon-ivy  iJie  thread  hy  luMch  it  is 
fixed  to  the  plant. 


Fig.  39. 


Male  {above)  and  j emale  Moth 
with  Cocoon  (below). 


IMAGINA.L    LIFE. 


^9 


The  life  of  the  imago. 

The  life  of  the  imago  varies  much  in  leng-th  in  the  different  groups. 
Reproduction  being  the  principal  business  of  this  period,  the  imago  com- 
monly dies  as  soon  as  mating  and  egg-laying  are  completed.  In  the  moths 
and  butterflies,  courtship,  mating  and  egg-laying  may  occupy  a  few  days 
or  more  rarely  a  faw  weeks.  The  imago  has  no  necessity  to  provide 
for  her  young  further  than  by  laying  her  eggs  in  a  suitable  place. 

In  the  H//menoptera,  on  the  other  hand,  the  parent  has  to  provide  for 
her  young  or  actually  feed  them,  as  the  larval  period  is  one  of  helplessness 
during  which  the  grub  feeds  on  the  stored  up  food  or  is  fed  by  the 
parent ;  so  also  the  life  of  the  imago  is  prolonged  until  she  has  fully 
provided  for  the  new  generation  or  done  her  share  of  the  work  of  the 
nest.  Between  these  two  extremes  are  many  shorter  or  longer  imaginal 
lives.  Climatic  conditions  may  determine  the  length  of  the  life  as  in  the 
grasshoppers  and  locusts,  the  Bombay  locust  living  as  imago  for  nine 
months  until  it  can  lay  e^gs,  whilst  allied  grasshoppers  live  as  imago  for 
some  six  weeks  only.  The  May-flies  live  for  very  short  periods,  the  long 
nymphal  life  being  the  active  period.  The 
dragon-flies,  on  the  other  hand,  have  a  long- 
life  both  as  nymphs  and  imagines.  Coleop- 
tera  live  long  and  can  survive  long  periods 
when  food  is  scarce  and  they  are  waiting 
until  conditions  are  again  favourable  for 
egg-laying.  Ilemiptera  and  Biptera  have 
long  lives  as  imagines,  the  preliminary 
stages  being  proportionately  shortened. 
There  is  no  general  rule  and  it  varies  from 
species    to   species.     The     activities   of    an 

insect  are  not  to  be  measured  by  its  life  in 
.         .        ,  ,         .     .         *^  Fig.  40. 

the  wmged  state  when  it  is  most  apparent  wingless  female  Wasp. 

to  us,  but  by  its  whole  free  life  as  larva  or  {The  male  is  winged.) 

nymph  and  as  imago.  In  some  the  first  predominates,  in  others  the  latter. 
In  exceptional  cases,  both  sexes  are  not  equally  developed,  and  in 
general  it  is  the  females  which  are  the  least  developed.  In  the  "  Bag- 
worms^'',  the  female  remains  as  an  imperfect  pupa  and  does  not  become 
Avinged  or  leave  the  shelter  of  the  larval  case,  wliilst  the  male  becomes 
winged  and  seeks  the  female  (fig.  41).  In  other  moths  the  female  may 
be  active  but  unwinged.  In  the  Aphides,  the  females  are  frequently 
unwinged,  the  males  winged.  This  is  the  invariable  rule  in  the  Scale 
Insects  and  Mealy  Bugs,  in  which  the  females  only  moult  twice   and 


.30 


LIFE    HISTORY    AT^D    HABITS. 


remain  unwing'ed ;  whilst  the  males  pass  through  a  transformation  and 
emerg-e  as  tiny  flying  insects  with  but  one  pair  of  wings  (fig.  43). 
These  are  instances  of  incomplete  development  and  are  not  to  be  confused 
with  the  differences  between  the  sexes  discussed  in  a  later  section. 

Hibernation  and  Broods. 

Insects  are  unable  to  live  and  breed  continuously  throughout  the  year, 
except  in  places  Avith  a  general  uniformity  of  conditions  throughout  the 
whole  year.     In  the  plains  of  India,  three   causes  combine  to   check  the 


Fig.  41. 
The  Mice  Leaf  Bag-ivorm.    a,  male  moth  ;  h,  female  adult,  an  imperfectly  developed 
moth  ;  c,  caterpillar  in  case  of  leaves, 

continuous  growth  and  breeding  of  insect  life  ;   these  are   cold,   excessive 
dry  heat  and  absence  of  food. 

A  great  number  of  insects  are  inactive  in  the  cold  weather  and  are 
then  said  to  hibernate ;  as  the  temperature  falls  these  insects  become  torpid, 
remaining  inactive  until  the  temperature  rises.  Hibernation  is  not  uni- 
versal ;  many  pests  are  active  in  the  cold  season,  attacking  the  rabi  crops ; 
others  emerge  from  hibernation  in  time  to  attack  the  ripening  crops.  J'he 
occurrence  and  period  of  hibernation  depend  largely  upon  climatic  condi- 
tions ;  the  temperature  does  not  fall  evenly  throughout  the  plains  of  India, 
and  a  species  that  hibernates  in  one  locality  may  not  do  so  in  another. 
Much  has  yet  to  be  learnt  of  hibernation  ;  few  insects  are  active  in  the 
cold  weather  in   dry  cold  localities;   few  hibernate  in  warmer,  damper 


IJIBEllNATIOX, 


31 


localities.  The  rise  of  tempevatiu'c  after  the  cold  weather  does  not  affect 
all  species  alike;  one  will  emerge  Aveeks  before  another.  In  rare  cases 
all  of  one  species  will  emerge  with  extraordinary  unanimity  Avhcn  the 
temperatiTre  rises.  It  is  not  uncommon  to  find  enormous  numbers  of  one 
species  of  a  moth  flying"  in  one  week,  giving"  place  next  week  to  another 
species  which  has  emerged  later. 

Hibernation  is  passed  in  all  stages ;  it  is  as  yet  impossible  to  give 
accurate  general  statements,  but  one  may  say  that  many  OrUioptera 
hibernate  as  eggs,  as  do  one  family  of  butterflies ;  many  Hymenoptera 
and  Coleoptera  hibernate  as  imagines,  others  as  pupae.  Lejndoptera  com- 
monly hibernate  as  pupre  or  larvse,  though  some  butterflies  do  so  as  eggs. 
Dijitera  hibernate  as  pupae  to  some  extent,  Hemiptera  as  imagines  or  eggs. 

After  the  cold  weather  there  usually  follows  a  period  of  dry  hot 
weather  prior  to  the  rainy  period.  Little  is  known  as  to  the  manner  in 
which  insects  pass  through  this  period.     Many  species  that  emerge  from 


Fig.  42. 
Scale  Insect  on  Tea.     a,  adult  female  scales  ;  h,  male  and  female  scales  after  first  monlt ; 
c,  female  scales  i  d,  male  scale ;  e,  tuinged  male;  f,  antenna  of  male  .• 
all  enlarged  except, &  and  b, 


32  LIFE    HISTORY    AND    HABITS. 

hibernation  have  one  brood  between  the  cold  and  hot  weather  and  then 
become  torpid,  either  from  absence  of  food  or  from  the  excessively  hot 
and  dry  conditions.  In  many  cases  this  period  is  simply  a  continuation 
of  the  hibernation ;  the  torpidity  due  in  the  first  place  to  cold  appears  to 
g-ive  place  to  a  torpidity  due  to  heat  and  drought  ;  or  we  may  consider 
it  as  due  to  the  absence  of  food.  For  many  species  there  is  food 
only  during'  the  wet  season,  so  that  insects  emerg-ing-  too  soon  would 

find  no  food. 

On  the  other  hand,  we  find  insects  emerging"  at  the  commencement 
of  the  hot  weather,  living  as  imagines  till  the  rains  if  food  is  not  available, 
but  laying  eggs  and  producing  a  new  brood  if  food  is  available.  This  is 
a  ciTriously  interesting  fact  not  yet  fully  understood.  For  instance,  if 
cotton  grows  continuously  through  the  cold  weather  and  the  hot  weather, 
we  find  its  pests  attacking  it  at  the  commencement  of  the  hot  weather ; 
should  the  cotton  however  be  dead,  we  find  the  same  insects  apparently 
living  as  imagines  or  still  hibernating.  When  well  irrigation  is  practised 
in  the  hot  weather,  there  is  food  for  some  insects  in  the  irrigated  crops, 
with  the  resiilt  that  these  insects  are  found  breeding  in  March  or  April ; 
in  the  same  district,  where  well  irrigation  is  not  practised,  we  find  these 
insects  still  hibernating  or  living  in  concealment  as  imagines.  These  are 
perhaps  the  exceptional  cases,  but  they  are  common  among  the  crop- 
destroying  insects. 

A  larger  number  of  insects  appear  to  continue  torpid  after  the  cold 
weather  and  until  the  rains.  But  again,  such  is  the  variety  of  insect 
life  that  general  statements  are  of  little  use.  Many  insects  are  most 
active  in  the  dry  hot  weather  ;  the  wasps  make  nests,  the  first  parasites 
appear,  the  dung-rolling  beetles  are  seen.  Ants,  termites  and  other 
insects  are  active.  If  we  turn  to  crop  pests,  it  is  not  far  from  the  truth 
to  say  that  (1)  they  continue  hibernation  or  (2)  they  emerge  and  lay 
eggs  on  the  crops  if  available  or  (3)  they  live  as  imagines  until  the  rains. 
The  question  of  available  food-plants  is  apparently  the  decisive  factor ; 
sugarcane  pests  are  very  active  in  the  hot  weather,  but  the  conditions  of 
course  approximate  to  those  of  the  ]'ains,  there  being  food  and  moisture 
available. 

The  result  of  these  periods  of  rest  is  that  for  every  species  there  is  a 
definite  time  during  which  the  imagines  emerge  and  lay  eggs.  IXiring 
one  week  there  will  be  an  abundance  of  a  particular  moth  emerged  from 
hibernation.  The  period  may  be  longer  or  shorter,  but  there  is  for  every 
species  some  period,  at  the  commencement  of  the  rains  or  of  the  hot 
weather,  when  ep-gs  are  laid,  and  shortly  after  which  the  first  brood  of 
Caterpillars  emerges.     If  all  the  imagines  emerged  on  the  same  day,  we 


BiJOODs.  33 

slioiild  get  our  caterpillars  a})pearing'  on  the  same  day  and  a  uniform 
succession  of  broods  throug-lumt  the  active  period.  This  is  not  the  case, 
and  though  the  first  brood  of  caterpillars  may  come  at  one  time,  the 
later  ones  become  irregular.  We  may  take,  as  an  instance,  a  moth  having 
a  life  history  period  from  egg  to  moth  of  six  weeks ;  if  Ave  get  the  moths 
out  on  March  the  4th,  the  eggs  are  laid  by  March  the  10th,  the  cater- 
pillars appear,  say,  by  March  the  15th,  become  pupae  about  April  the 
15th  and  moths  about  the  22nd  April.  We  find  caterpillars  again  about 
the  beginning  of  May ;  later  broods  of  caterpillars  would,  if  food  were 
available,  come  about  the  middle  of  June  and  the  end  of  August,  and 
the  caterpillars  of  the  middle  of  October  would  hibernate  ;  there  would 
thus  be  outbreaks  of  the  caterpillar  in  the  latter  half  of  March,  begin- 
ning of  May,  latter  half  of  June,  beginning  of  September  and  latter  half 
of  October ;  five  attacks  of  this  pest  in  all  if  food  is  abundant  and  all 
come  out  together.  Actually  this  rarely  if  ever  occurs,  but  one  can  in  some 
cases  trace  the  broods  through  the  year  and  expect  them  at  their  regular 
dates.  In  most  cases  the  imagines  do  not  all  emerge  together  and  the 
subseq^^ent  irregularity  of  development  of  the  individuals  accounts  for 
the  irregularity  of  the  broods.  The  appearance  of  large  numbers  of  a 
particular  insect  at  regular  intervals  can  be  accounted  for  if  one  traces 
its  history  and  knows  when  it  emerged  from  hibernation.  We  must, 
however,  guard  against  expecting  regular  broods ;  it  is  often  stated  that 
a  particular  pest  has,  say,  four  broods  a  year ;  actually  it  is  found 
throughout  a  long*  period,  some  being  late,  some  early,  some  at  the 
proper  time.  The  four  broods  are  not  regular,  and  though  the  insect 
does  breed  four  times  in  the  year,  all  do  not  breed  at  the  same  time. 


CHAPTER  III. 

FORM  AND  COLOUR. 

IF  we  examine  an  insect,  we  can  possibly  deduce  from  its  form, 
structni-e  and  colour  many  facts  as  to  its  probable  habits  and  habitat. 
The  complete  structure  of  an  insect,  as  well  as  its  life  history,  is  inti- 
mately correlated  with  tlae  predominating-  motives  of  its  life,  search  for 
food,  escape  from  enemies,  reproduction  of  the  species. 

In  all  insects  the  modifications  of  form  and  colour  which  are  cor- 
related with  sex  and  reproduction  appear  only  in  the  imago  stage. 
Larvae  are  of  no  sex  and  even  the  larger  nymphs  of  the  Orthoptera 
display  only  minor  sexual  differences,  the  sexual  characters  not  being 
matured  until  the  final  moult.  In  the  higher  insects  the  search  for 
food  is  confined  to  the  larval  stage,  not  wholly  but  very  largely.  We  may 
reo-ard  the  division  of  the  life  of  an  insect  into  distinct  periods,  in  one  of 
which  the  search  for  food  is  the  principal  business,  in  the  other  repro- 
duction, as  a  valuable  adaptation,  which  may  account  for  the  success  of 
the  insect  group  over  others. 

In  nearly  all  insects  the  necessity  of  special  devices  for  offence  or 
defence  lasts  throughout  the  entire  life.  The  exceptions  are  the  insects 
which  live  hidden,  such  as  the  borers ;  with  these  exceptions,  every 
insect  must  be  protected  from  foes,  and  in  all  stages  we  find  that  there 
are  numberless  special  contrivances  for  securing  immunity. 

It  is  impossible  to  discuss  fully  the  varieties  of  form  and  colour 
found  in  insects.  There  is  a  meaning  in  the  colour  scheme,  the  details 
of  the  structure,  the  general  form  and  appearance  of  every  species,  which 
we  could  find  if  we  were  fully  acquainted  with  its  habits.  We  are  only 
slio-htly  acquainted  with  the  lives  of  any  insects,  and  most  live  in  ways 
totally  unknown  to  us.  It  is  possible  only  to  outline  a  few  generalities, 
principles  that  extend  over  large  groups  of  insects  and  give  us  a  clue 
to  the  method  of  understanding  the  significance  of  form  and  colour  in 

insects* 

Size. 

The  general  conception  of  the  size  of  an  insect  is  perhaps  di  some- 
thing about  as  large  as  a  bean  or  larger.  The  majority  of  species  are, 
however,  less  than  one  quarter  of  an  inch  long;  it  is  misleading  to 
judge  from  our  observation  of  insects,  since  the  larger  ones  catch  the 
eye,  are  more  easily  studied  and  far  more  easily  preserved,  whilst  the 
smaller  insects  escape  notice  and  are  passed  by. 


SI2E. 


35 


It  is  not  Tiiireasonable  to  suppose  tliat  a  smaller  insect  requiring"  less 
food  and  able  to  live  long-  periods  on  little  nourishment  thrives  where  a 
larg-er  insect  could  not.  Probably  it  can  reproduce  more  rapidly,  it 
offers  less  inducement  to  enemieS;  and  on  the  whole  may  be  more  suc- 
cessful.    These  considerations  probably    determine  the    limit  of  size    and 


Fia.  43. 
Tlie  Oleander  HatoTc  Moth  :  one  of  the  siviftest-fijing  of  the  large  moths  of  India. 

the  average  is  far  lower  than  is  generally  supposed.  Large  insects  are 
rarely  so  injurious  or  plentiful  as  small  ones.  Locusts  of  course  are  an 
exception.     The  very  large  ones  cannot  perhaps  multiply  sufficiently  fast, 


Fig.  44, 
The  Hed  Borer  of  Coffee  :   caler]}illar;  pu]pa>  as  it  wriggles  out  of  the  hi  anch  ;  moth. 

d2 


X 


€.u.^  lyoc.      C(>//k  ct-e. 


36 


FORM    AND    COLOUK. 


whilst  the  small  forms  have  an  enormously  rapid  power  o£  multiplication. 
In  any  one  species  the  size  is  usually  constant,  but  is  not  a  character 
that  can  be  used  to  discriminate  species.  Some  species  are  very  variable 
in  size,  and  males  are  frequently  smaller  than  females. 


Fig.  45. 

Common  Cochroach. 


Form. 

The  fact  that  an  insect^s  form  is  correlated  with  its  habitat  and  by 
the  necessities  of  procuring  food  is  abundantly  manifest.  Insects  in 
general  are  somewhat  cylindrical,  a  form  that  allows  of  twisting-  and 
flexible  movements.  This  jjersists  in  flying"  insects 
(flg.  -iS),  as  offering  less  resistance  to  the  air  and  is 
also  well  seen  in  most  larvae.  Boring  insects  are 
extra-cylindrical,  as  it  were,  fitting  tightly  in  the 
tubular  burrows  they  make  or,  as  in  the  beetle  grubs, 
having  a  special  cushion-like  projection  that  fits  the 
bnrrow  tightly  and  facilitates  locomotion  (fig.  88). 

Many  insects  are  flattened;  bark  beetles  and 
similar  insects  that  find  food  between  the  bark  and 
the  wood  are  often  flat,  to  the  extreme  of  being 
leaf-like.  Ground  beetles,  cockroaches  (fig.  45)  and 
other  insects  that  live  on  the  ground,  hide  under  stones,  and  run  fast,  are 
usually  flattened.  So  too  are  some  caterj)illars  (fig.  47)  that  cling  tightly 
to  the  leaves  of  plants,  and    leaf-miners    which    find   their   food   between 

the  upper  and  lower  epidermis 
of  a  leaf.  The  tortoise  beetles 
are  flat  and  can  cling  very  tightly 
to  a  smooth  leaf  after  the  manner 
of  a  limpet  on  a  rock.  The  praying 
mantises  are  often  formed  like  a 
grass  stem,  and  lurk  in  the  grass  in 
the  hope  of  unwary  insects  mistak- 
ing them  for  a  grass  stem  and  so 
getting*  Avithin  their  reach.  Others 
resemble  dry  sticks  and  live  on  dry 
bushes.  The  green  grasslioppers 
(fig.  20)  for  a  similar  reason  are 
formed  so  as  to  suggest  a  green 
leaf   and    deceiAX'   butterflies.     Mag- 

„,    ,,  '  ,  *  .     ^  y'ots    that   live   in    decaying   matter 

The  Buj  ^  an  example  of  a  Jlal  insect.         ^  ti 

{Magnified.)  are    smooth     and     Avorm-hke,     with 


FOKM. 


37 


specially  laro-e  stio-mata  at  the  tail  so  that  the  mao'o-ot  may  lie  embedded 
in  li([\iid  and  still  obtain  air. 

These  modifications  are  necessitated  by  the  search  for  food  ;  others 


Fig.  47. 
Sliiff  Caterpillar,  specially  adapted  to  clinri  ticjlitlif  to  leaf. 

are  of  use  in  conferring"  immunity  from  foes.     "  Cryptic  form  "  is  most 


Fig.,  48. 
Jjeaf  Insect. 


38 


FORM   AND   COLOUR. 


commonly  associated  with  cryptic  colouring  and  is  seen,  for  instance,  in 
the  stick  insect  whose  long'  and  slender  body  is  formed  and  coloured  to 


Fig.  49. 
Leaf  Insect. 


resemble  the  twigs  amongst  which  it  lives  ;  we  suppose  this  to  he  a 
device  to  hide  the  insect  from  birds.  So  too  in  the  Leaf  Insect  (fig.  49) 
which  bears  an  extraordinary  resemblance  to  a  bunch  of  green  leaves. 
The  intensely  hard  spines  found  ou  some  beetles  and  bugs,  the  thick 
coating  of  hairs  (fig.  50),  the  very  thick  hard  masses  of  chitin,  are 
believed  to  make  insects  distasteful  to  birds  and  possibly  to  predaceous 


PKOTECTTVE    DEVICES. 


89 


Fig.  50. 

Spini/  Caterpillar,  the  spines  poisonous, 

insects.  The  unpleasant  odour  of 
bugs  is  certainly  a  protective  device  ; 
so  too  are  the  bad  tasting  oils  of  the 
blister  beetles  and  ladybird  beetles. 
Some  beetle  grubs  cover  themselves 
in  their  own  excrement,  others 
cany  their  cast  skin.  The  Lace- 
wing  grub  carries  a  pile  of  the  cast 
skins  of  its  victims.  Stings  are 
probably  protective,  though  birds 
and  lizards  eat  bees.  An  unpleasant 
taste  is  also  probably  protective 
and  is  associated  with  the  scheme 
of  colouring  known  as  warning 
colouration. 

Sex  also  profoundly  modifies 
the  structure  of  insects.  The 
internal  organisation  is  of  course 
totally  distinct  and  there  are  com- 
monly external  organs  which 
readily  reveal  the  sex.  (fig.  52). 


Fig.  51. 

The  Med  Ant,  a  wine/less  toorker,  mature 
but   sexless  ;    their   pungent    flavour 
and  keen  bite  is  their  protection. 


40 


POKM    AND    COLOUE. 


Fig.  52. 
Female  Long-horned  Grasshopper,  to  show  the  sword-like  oviposilor. 

In  general  where  there  is  a  diver- 
sity of  sex,  the  male  is  the  smaller 
(fig.  53)  ;  both  sexes  are  frequently 
similar  in  size  and  external  characters, 
the  sex  being  determined  only  by  dis- 
section. In  many  Orthoptera  the  males 
are  smaller  and  differently  coloured,  in 
rare  eases  being  very  unlike  the  female 
in  general  appearance.  The  male  stick 
insects  are  often  winged  when  the 
females  are  unwinged. 

There  is  little  or  no  difference 
between  the  sexes  in  Nenroptera. 


Fig,  53, 

Male  and  Female  Moth,  the  smaller 
male  above. 


Fig.  54. 
Male  Ant, 


Fig.  55. 
Worker  Ant.  (Magnified.) 


SEX, 


41 


In  many  Hf/menoptera  tho  sexes  are  very  distinct.  In  the  social  insects 
this  is  carried  to  a  g'reat  extreme  and  we  find  only  a  small  number  o£ 
individuals  with  reproductive  organs,  the  majority  being-  sexless  workers 
(fig's.  51  and  55).  In  solitary  bees  and  Avasps,  there  is  a  distinct  male, 
and  in  one  family  the  female  is  wingless,  the  male  Avinged  (fig.  40). 
Beetles  display  little  external  difference ;  exceptionally  the  male  bears 
horns  (fig.  56)  ;  in  some  wood-boring  beetles  the  male  is  wingless  (fig.  86). 


Fia.  56. 
3Iale  Stag  Beetle, 


Butterflies  display  great  sexual  differences  in  colour,  form,  etc. ;  we  repro- 
duce one  species  (figs.  58-59)  in  which  they  are  very  strikingly  different. 
Moths  rarelj-  display  great  or  noticeable  differences,   more  often   small 


42 


FORM   AND   COLOUR. 


distinctions  only.  Females  are  in  some  cases  wingless.  In  flies 
tliere  are  seldom  striking*  differences ;  male  mos(piitoes  have  large 
reathery  antennce^  females  smaller  ones  (fig.  00).  Bugs  are  rarely  dis- 
tinguishable^ but  some  of  the 
predaceous  species  have 
clearly  distinct  sexes.  In 
Aphides,  males  are  often 
absent ;  in  Mealy  Bugs  and 
Scale  Insects,  the  male  alone 
is  winged,  the  female  wing- 
less and  degraded. 

Male  insects  commonly 
produce  sounds  or  songs. 
Grasshoppers  chirp  by  rub- 
bing the  hind  leg  along  the 
front  wing* ;  green  grass- 
hoppers have  a  powerful 
Fig.  57.  sound-producing        apparatus 

Female  Stag  Beetle.  ^t     the    base    of    the     wingS. 

Crickets  produce  a  shrill  loud  noise.  All  of  these  insects  also  have 
ears  with  which  to  hear  the  music  they  produce.  Beetles  have  a  very 
great  diversity  of  apparatus  for  producing  sounds.  The  best  known 
noisy  insects  are  the  Cicadas  which  live  in   forests ;  they  are  possessed 


Fig.  58. 
Male  Butterfltf. 


SONG. 


43 


^ 

^ 

i 

f 

9 

r 

1 

^4 

pi 

F"      .«M^ 

J 

^9fe^^. ' 

\    jju^ 

. 

Fig.  59. 
Vernal^  Sutterfltj. 


o£  a  complicated  sound  organ  at  the   base   of   the   abdomen,    with   which 
they  produce  a  pecuHarly  piercing  and  shrill   noise.     A  few   bugs   can 


Fig.  63. 
4  Mosquito,  male  alove,  female  leloio.     {Magnified.) 


44. 


FOT?M    AND    COLOTTE. 


sino-  or  chirp.  Song'  is  mainly  ooncernod  Avitli  sex  and  is  possibly  one  of 
the  few  means  by  Avhich  the  male  captivates  or  pleases  the  female ;  song- 
may  also  be  connected  with  the  fact  that  the  male  is  not  burdened  with 
the  chief  care  of  life^,  the  satisfactory  deposition  of  the  eggs,  and  so 
utilizes  his  superfluous  energy  in  song.  Another  manifestation  of  sexual 
difference  may  perhaps  be  found  in  the  luminous  insects. 

Colour. 

All  insects  which  live  in  the  open  air  are  coloured  in  a  more  or  less 
complex  manner  ;  the  scheme  of  colouring  is  in  many  species  variable 
within  certain  limits,  but  generally  is  uniform  and  fixed  in  all  individuals 
of  one  or  both  sexes  of  the  same  species.  These  colour  schemes  are 
evidently  important  to  the  welfare  of  the  insect,  and  attempts  have  been 
made  to  elucidate  the  general  principles  that  underlie  them  ;  no  two 
species  have  precisely  the  same  form  and  colour,  but  large  numbers  have 
a  similar  colour  scheme,  differing  in  detail  in  each  species  but  agreeing  in 
the  general  effect. 

We  have  seen  above  that  some  insects,  such  as  stick  insects,  are  so 


Fig.  61. 
Mcth  on  Barh  of  Tree.     An  instance  of  cryptic  inarking. 

formed  as  to  closely    resemble   their    surroimdings   and   so  escape  notice ; 
this  is  associated  with  colouring,   and   the  conjunction  of  cryptic  form 


CRYPTIC    COLOUIJ. 


46 


and   colouring'    may    render    a    larg-e   insect    indisting'uisliable     from   its 

surrounding's.     Leal    insects    are    coloured    like   a    leaf,    wliicli    may    Le 

"•reen  or  dry.     Many  moths    (lig\   Gl)  sit  with  expanded  wings  and  the 

colour  scheme  blends  with  the  bark 

on  which  they  sit  so  well  that  the 

moth  escapes    notice.     Others    sit 

with     folded     wings    and    exactly 

resemble  bark  ;   their  lower  wings 

are  then  hidden  and  may  be  brightly 

coloured.     Grasshoppers  commonly 

have  cryptic  colouring,  some  being 

dry-grass  colour,  others  green-grass 

colour,    and   so    on.     Grasshoppers 

that  live  in  the  fields   and   sit   on 

the  ground  are  earth  colour  (fig.  02) 

and'   have     roughened    backs    like 

a  lump  of  soil. 

Cryptic  colouring"  is  very  com- 
mon, usually  combined  with  cryptic 
form  ;  it  may  occur  in  two  different 
colour  schemes  in  the  life  of  an 
insect,  the  change  occurring  when 
the  changed  surroundings  make  it 

necessary.  Thus  a  young  grasshopper  that  lives  in  gi'een  gi'ass  is  gi'eenj 
but  becomes  dry-grass  colour  when  the  grass  ripens  and  the  insect 
becomes  full  grown.  A  caterpillar  that  sits  on  a  leafy  tree  is  green,  per- 
haps so  long  as  it  remains  there ;  when  it  has  to  crawl  down  the  trunk 
to  reach  the  grovmd  and  pupate,  it  becomes  brown,  as  the  green  would 
make  it  conspicuous  against  the  bark  of  the  tree.  Those  larvse  which  live 
in  nests  or  other  hidden  spots  change  but  little  at  each  moult  unless  their 
habits  require  a  change.  The  changes  may  be  small  and  imperceptible 
or  very  marked,  and  bear  a  close  relation  to  the  differing  habits  of  the 
young  and  the  old  insect.  The  same  is  true  of  the  nymphs  of  the 
OrtJioptera  and  Hemiptera.  With  every  moult  there  are  distinct  changes 
not  due  alone  to  the  gradual  development  of  the  wings  and  other 
imaginal  characters,  but  to  changes  of  colour  and  form  necessitated  by 
changing  environment.  The  very  young  nymphs  of  a  grasshopper,  for 
instance,  which  live  concealed  in  grass  require  a  very  different  colouring 
from  the  half -grown  insect  which  leaps  actively  about  in  the  open  ;  the 
colour  therefore  changes  at  each  moult,  adapting  the  insect  to  its 
increased  activities  and  gradually  giving  place  to  the  colour  scheme  of 


Surface  Grasshoppei', 


46 


FORM   AND    COtOUR. 


the  imago,  wliicli  usually  eoinmencos  to  apj)eav  in  the  last  moult  but 
one  or  two.  There  are  countless  instances  of  these  changes  and  we  may 
constantly  see  instances  of  cryptic  colouring-. 

On  the  other  hand,  we  find  some  insects   very  vividly  and  brightly 
coloured,   so  that  they  stand  out   strongly   against   their   surroundings. 


Fia.  G3. 

The  South  American  Caterpillar  ivhich  suggested  "  warning  colouration '';  tJie  light  bunds 
are  bright  gellow,  the  feet  and  process  red. 

These  insects  are  usually  distasteful  to  birds  and  predaceous  insects 
either  from  their  taste,  odour,  or  the  oils  they  excrete.  Their  striking 
colouration  is  accordingly  supposed  to  be  "  warning ",  i.e.,  warns  the 
birds  that  the  insect  is  unpleasant.  A  young  bird  eating  such  an  insect 
associates  the  bright  colours  with  the  unpleasant  taste  ;  it  then  refuses 
to  eat  similarly  coloured  insects  and  warningly  coloured  insects  escape. 
There  are  many  insects  supposed  to  be  warningly  coloured  ;  red,  orange 
or  yellow  with  black  are  common  warning  colours.  Most  bees  and  wasps, 
ladybird  beetles,  some  blister  beetles,  and  some  butterflies  are  so  coloured. 


Fio.  64. 
Moth  of  the  precious  Caterpillar,  coloured  cryptically  in  grey  and  hlacl. 


WARNING    COLOUR. 


4t 


Dragon  flies  are  often  brilliant,  Avith  red,  bhie,  yellow,  green  and  other 
vivid  colonrs  associated  with  black.     A  few   grasshoppers   are  very  vivid. 
Warning  colouring  is  very   common.     It    is  found   that  many  insects 
exactly  copy  the  markings  of  such  warniiigly  coloured  insects  ;  the  former 


Fig.  65. 
Warningly  coloured  Beetle. 

are  not  distasteful,  have  no  unpleasant  taste  or  smell,  but  escape 
because  they  look  like  nasty  butterflies  or  beetles.  This  is  known 
as    Batedaii    mimicnjy   after   its    discoverer.     Many   Danaid  butterflies 


A 

\\ 

"'--^ 

Fig,  66.  Fig.  67. 

A  Wasp,  protected  hy  its  stiny  and  A  Fly,  harmless  and  edihle,  lohtch 

xmrningly  coloured.  mimics  the  Jl^asj). 

are    Avarningly    coloured;     other     butterflies,    not   of    this    group,     but 

living  in  the   same   locality,  exactly   mimic  the  Danaid  in   form  and 

colour  ;   they  look  closely  alike  and  only  careful  examination  shows  that 


48  POEM    AND    COLOUt;. 

the  latter  are  different  in  fundamental  structure.  The  edible  mimic 
escapes  through  its  resemblance  to  a  distasteful  insect.  This  form  of 
mimicry  is  common.  Edible  butterflies  mimic  nasty  ones ;  moths  mimic 
butterflies ;  flies  mimic  moths ;  flies  also  mimic  bees  or  wasps ;  there  are 
abundant  instances  which  can  be  cited  among-  Indian  insects  (figs.  6G-68). 

Another  form  of  mimicry  occurs  when  we  find  in  one  locality  a  large 
number  of  insects  with  a  general  warning  scheme  of  colour,  say  black 
and  yellow.  Among  all  these  insects  having  a  similar  colour  scheme 
some  are  genuinely  nasty,  protected  by  unpleasant  taste,  bad  scents, 
poisonous  bite,  sting,  etc.,  so  that  birds  will  not  willingly  eat  them. 
Others  are  not  unpleasant,  but  pretend  to  be  so  by  "  adopting  "  the  same 
scheme  of  colouring.  This  is  called  Mullerian  mimicry  and  is  also 
common.  It  must  not  be  thought  that  an  insect  can  change  its  colour 
voluntarily ;  the  colour  of  insects  is  fixed  and  all  of  a  species  are  coloured 
much  alike ;  but  it  is  believed  that  in  the  evolution  of  insects,  the  species 
"  adopted  ^^  or  gradually  acquired  colour  schemes,  and  so  the  warningly 
coloured  insects  arose  first  and  other  species  later.  If  we  disbelieve 
evolution,  we  may  say  that  the  mimics  were  made  like  the  warningly 
coloured  insects,  and  any  misconception  due  to  the  deficiencies  of  the 
terms  used  will  be  avoided.  A  few  insects  are  so  coloured  and  formed  as 
to  resemble  unpleasant  substances ;  thus  the  larvae  of  the  citrus  butterflies 
are  not  unlike  the  excrement  of  a  bird  and  feed  on  the  leaves  in  such  an 
attitude  as  to  assist  the  resemblance  (fig.  195) 


Fig.  68. 
A  common  Fly  {lejl)  vliich  Viimics  Ihe  common  Bee  (ru/li)  mid  so  escapes  'its foes. 

{Magnijled.) 

Deceptive  colouring  is  very  common ;  it  is  apparently  designed  to 
deceive  birds  and  is  useful  when  an  insect  is  in  flight.  The  Leaf  Butterfly 
is  an  instance ;    the  upper  wings  are  brightly  coloured  and  the  insect  in 


DECEPTIVE   COLOUH.  49 

flight    is    conspicuous;   it   flies  along   and    suddenly   settles    wiili   wings 


Fig.  69, 

The  Hooded  Grasshopper,  wliicli  combines  projection  due  to  the  hard  sharp  hood  with 
cryptic  and  deceptive  colonring. 

folded,  exactly  resembling  a  dead  leaf ;  the  suddenness  with  which  the 
bright  colours  of  the  upper  surface  vanish  is  extremely  deceptive  and 
makes  it  very  difficult  to  distinguish  the  butterfly.  Grasshoppers  have 
the  same  colouring,  the  lower  wings  being  often  brilliant  and  very  notice- 
able when  the  insect  flies  ;  it  then  suddenly  settles  with  folded  wings 
and  the  colours  exactly  blend  with  the  dry  grass  ;  it  is  impossible  to 
see  where  it  is  and  Ave  may  conjecture  that  a  bird  is  also  deceived. 
This  is  a  common  scheme  of  colour  and  is  usuallj^  shown  l)y  the  upper 
wings  being'  cryptic,  the  lower  verj^  bright  and  conspicuous.  Moths, 
grasshoppers  and  other  cryptically  coloured  insects  are  the  best  instances. 

Many  butterflies  have 
beautiful,  diverse  colour- 
ing, which  does  not  fall 
into  any  of  the  above 
schemes.  Some  have 
very  conspicuous  marks 
on  the  hind  angle  of  the 
wings  or  on  the  front 
wings;  these  are  sup- 
posed to  mislead  a  bird 
which  attempts  to  seize 
them,  the  bird  snatch- 
ing at  the  conspicuous  y\g.  70. 
spot   on   the   wing   and  so                a  Butterfy  ->nth  eye  spots  to  deceive  birds. 


50 


FOllM    AND    COLOUn. 


missing  the  l)utterfly  which  loses  a  part  of  its  wing*  but  escapes  alive.     This 
may  seem  to  be  a  fantastic  explanation,  but  it  is  borne  out  by  good  evidence. 

Other  butterflies  are  perhaps  coloured  in  rough  imitation  of  their 
surroundings  as  seen  from  above,  i.e.,  their  colouring  blends  with  the 
light  and  shade  of  vegetation  when  they  are  looked  at  from  above  as  a 
bird  looks  at  them.  We  cannot  be  certain  of  this  since  we  see  them 
from  about  their  own  level,  but  the  explanation  of  the  colouring  of  many 
butterflies  is  probably  to  be  found  in  this.  A  few  insects  have  apparently 
a  scheme  of  colouring  that  is  meant  to  terrify  an  enemy  or  frighten  it 
away.  Such  are  the  Hawk  Moth  Caterpillars,  which  when  alarmed  sud- 
denly expose  large  eye-like  spots  and  look  like  a  ferocious  snake  ;  others 
simply  look  bizarre  and  fearful,  if  we  can  judge  from  what  we  imagine  a 
bird  feels  when  he  encounters  one.  Many  caterpillars  have  such  devices, 
coloured  spots  and  stripes,  brightly  coloured  filaments,  waving  hair  tassels 
and  the  like. 

These  are  the  principal  colour  schemes  found  in  insects,  but  still  we 
are  io-norant  of  the  significance  or  value  of  the  colouring  of  many  insects. 
Ground  beetles  are  commonly  black  or  very  dark  coloured,  perhaps  because 
they  live  in  hiding.  Many  are  white,  especially  those  which  come  out 
in  the  dusk,  and  this  may  facilitate  courtship  and  mating.  Colouring  is 
possibly  not  determined  by  utility  in  every  case,  but  is  simply  for  beauty, 
and  the  general  effect  of  insect  colouring  is,  from  man's  point  of  view, 
chiefly  one  of  beauty.  Possibly  this  is  the  case  also  from  the  insect's 
point  of  view,  and  though  necessity  is  considered,  the  whole  scheme  may 
be  primarily  for  beauty. 


Fig.  71. 

Lacewinc)  Bugs  ;  their  minute  size  is  shown  ly  the  hair  line. 

i^No  meaning  except  fure  leaiitg  can  he  assigned  to  their  delicate  ornamentation.) 


COLOUK    SCHEMES,  51 

We  may  remember  tliat  llie  colour  schemes  of  tlie  very  great  majority 
of  insects  have  to  us  no  meaning*.  The  few  tliat  exhibit  Batesian  or 
]\Iullerian  mimicry  or  are  warningly  coloured,  arc  a  very  small  part  even 
of  known  insects.  The  ordinary  insect  picked  up  at  haphazard  does  not 
fall  into  any  class ;  we  can  see  sometimes  that  the  colouring  perhaps 
blends  in  several  scliemes,  cryptic,  warning,  sexual  and  the  like  ;  but  avc 
cannot  judge  in  tlie  least  of  the  real  value  or  significance  of  the  colour 
schemes  of  nine-tenths  of  the  known  insects.  It  would  not  be  surprising* 
if  a  growing*  knowledge  produced  a  far  profounder  and  truer  interpreta- 
tion of  colour  in  insects,  more  in  accordance  with  tlie  real  needs  and 
necessities  of  insect  life. 


pid 


CHAPTER  IV. 


Fig,  12. 
Ortho'pterous  Insect, 


CLASSIFICATION  AND  NOMENCLATURE. 

AVERY  laro-e  number  of  insects  are  known  to  occiir  in  India  as  in 
other  tropical  countries  which  it  is  no  easy  matter  to  classify.  Insects 
are  primarily  divided  into  nine  orders,  two  of  which  are  of  little  import- 
ance and  rarely  met  with. 
The  seven  larg-e  orders 
are  easily  distinguished 
B.ccording'  to  the  structure 
of  the  wings  and  mouth- 
parts  and  by  the  life  his- 
tory, A  knowledge  of 
classification  is  necessary 
to  enable  one  to  place 
every  insect  into  its  order ; 
one  then  knows  whether 
it  may  be  expected  to  have  a  metamorphosis  or  not,  and  one  has  a  clue  to 
its  probable  habits  and  nearest  allies.  It  is  not  necessary  in  these  pag-es 
to  go  further  than  the  principal  orders.  The  final  classification  into 
sub'families,  tribes,  genera  and  species  is  a  matter  of  special  study  and  is 
best  left  to  those  who  work  in  museums  and  study  only  the  dead  insect. 
The  student  will  require  also  a  knowledge  of  the  chief  families  of  each 
order,  but  this  point  cannot  be  entered  upon  here.  The  seven  principal 
orders  are  most  conveniently  known  by  their  scientific  names,  since  there 
are  not  in  all  cases  English  equivalents.  The  following  are  the  orders 
with  their  distinguishing  characters  : — 

Orthopterci  {orthos  = 

straight;  jo^<?r«  =  wings). 

Cockroaches,  leaf  and  stick 
insects,  locusts,  grasshopjiers 
and  crickets.  The  first  pair 
of  wings  are  narrow,  with 
straight  edges,  the  second 
pair  large,  folding  up  under 
the  first.  Biting  mouth-parts. 
No  metamorphosis. 
Pjjj  ;^3  This  order  is  easy  to  recog- 

:^europterous  Insect.  pise  by  their  thick^  coloured 


dKDEfiS. 


53 


upper  wing-s,  which  do  not  tit  tightly  to  the  body  but  project  beyond  the 
end  of  the  abdomen  (fig*.  72). 

Nenroptera  {neiiro  =  nevye ;  piera —  wings).  Termites,  ant-lions, 
drag'on-flies,  may-flies,  etc. 

The  wings  are  larg-e  with  many  veins  (nerves)  forming  a  network. 
Biting  mouth-parts.     A  metamorphosis  in  some,  not  in  others. 


Fig.  74. 
Hymenojptei'otis  Insect, 


Fig.  V5. 
Hymenopterous  Insect. 


Hymenojptera  {Jiymen  =  membrane;  ^^era:=  wings).  Bees,  wasps, 
ants,  etc. 

The  wings  are  small,  transparent,  with  few  veins.  Mouth-parts 
biting-  and  lapping.     A  metamorphosis,  the  larva  being  usually  a  helpless 


grub. 


Fig.  76. 
Coleopterous  Insect. 


Fig.  77. 

Coleoptermts  Insect  to  show  lower 

wings. 


Coleoptera  [coleon  =a  sheath  ;  jo^^m  =  wings) .     Beetles. 


54 


CLASSIFICATION    A^D    NOJtE.VCLATUllE. 


The  first  pair  of  wings  are  thickened^  fit  tig-litly  to  the  body  and 
make  a  sheath   for  the  large  folded  lower  wing-s.     Biting  mouth-parts. 

A  metamorphosis,  the  larva  being  an 
active  grub. 

These  are  easy  to  recognise,  the  hard 
upper  wings  meeting  in  a  straight  line 
over  the  back. 

Lepidoptera  {lejns  =  a  scale  ;  pfera  = 
wings).     Butterflies  and  moths. 

The  wings  are  larg-e,  clothed  in  fine 
scales. 

The  imago  has  a  suctorial  proboscis. 


Fia.  78. 
Lepidopterous  Insecf. 

A  metamorphosis,  the  larva 
being  a  caterpillar  with  biting 
mouth-parts. 

Diptera  {di  =  two;  ptera 
swings).  Flies,  mosquitoes, 
etc. 


^ 

■^/      a 

K 

^=> 

^- 

1 

HlL^ 

\ 

T 

i 

N 

- 

i 

f 

riG.  80. 

Semipterous  Insect. 


Fig.  79. 
Dipterous  Insect }  Larva  and  Pupa  belotv. 

One  pair  of  wings  only.  Suctorial 
mouth-parts.  A  metamorphosis,  the  larva 
being,  as  a  rule,  a  legless  maggot. 

Ilemiptera  (^<^y;^^  =  half  ;  ptera  ^ 
wings).     The  bugs. 

The  basal  half  of  the  upper  wings  often 
thickened.  Sucking  mouth-parts.  No 
metamorphosis. 

Distinguished  from  beetles  most  readily 
by  the  fact  that  the  wings  do  not  meet  in 
a  straight  line,  but  overlap. 


OHDMS. 


55 


Pig.  81. 
FovHeen-SpoHed  Leaf  Beetle. 

a.  Larva  ;  b,  Fwpa  ;  d.  Pupa  case  :  c. 
Imago.     All  magvified  but  d. 

is    more    difBcult ;    young 
Orthoptera  and  Bemiptera 
are    of   course    easily   dis- 
tinguished  by  the  mouth- 
parts.     A  caterpillar   with 
not    more    than    five   pairs 
of       sucker-feet      belongs 
to  Lepidoptera ;   if  it  has 
more,    it    is    one    of    the 
few    Jlymenoptera     whose 
larvre     resemble     caterpil- 
lars.       A     larva     without 
snclcer-feet   and   not  hairy 
is    prol)ably    Coleopiera   if 
it  has  a  well-marked  head, 


These  seven  orders  are  generally 
easily  distinguished ;  look  first  at 
the  wino-s,  then  at  the  mouth-parts  ; 
a  two-winged  insect  is  probably  one 
of  the  Biptcra;  an  insect  with  four 
clear,  transparent  wings  belongs  to 
NcuropUra  if  the  wings  are  large ;  to 
Tlymenoptera  if  they  are  small.  If 
the  wings  are  covered  with  scales,  it 
is  a  butterfly  or  moth ;  if  the  upper 
wings  are  hard  and  meet  in  a  straight 
line,  it  is  a  beetle,  but  if  one  lies  over 
the  other,  it  is  one  of  the  llemipUra. 
In  the  latter  case  a  glance  at  the 
mouth-parts  will  confirm  it. 

It  is  only  the  exceptions  to  these 
rules  that  make  classification  difiicult, 
and  as  the  apparent  exceptions 
are  numerous,  one  cannot  expect  to 
place  every  winged  insect  into  its 
order  by  superficial  examination. 
When  the  insect  is  young,  the  case 


Fig.  82, 
Lavm.  Pupa  and  Imago  of  a  ffymenopierom  Insect. 


56  ctASSIFiCATION    AND    NOMENCLATURE. 

and  Bipiera  if   it  is  without  any  definite   head.    There   are,  however, 


CL 


Fig.  83. 
Diplera;  Larva  on  left.  Pupa  in  middle 


.^1^>      •  ,r<'. 


-•sg 


It' 


Fig.  84 
Slug  Moth,     a,  h.  Caterpillar  s  c,  Cocoon; 
d,  Male  J  c,  Female 


,  Imago  on  right. 

no  means  of  classify- 
ing^ larvae  accurately 
except  by  rearing  them. 
The  same  is  true  of  pupse. ; 
but  if  the  pupa  is  sus- 
pended from  a  plant,  it 
is  probably  that  of  a 
butterfly;  if  it  lies  in  a 
silky  cocoon  or  in  twisted- 
up  leaves,  it  is  probably 
that  of  a  moth.  Should 
it  be  in  the  ground  with- 
out a  cocoon,  it  may 
emerge  as  a  beetle  or  a 
moth.  If  there  be  many 
in  a  nest  together,  they 
belong  to  Hj/menoptera. 
The  figures  of  different 
larvae  and  pupse  will  help 
in  classifying  them. 

The  following  English 
terms  are  generally  used 
for  the  larvae  of  different 
groups : — 

A  hop])er  is  the  young 
(nymph)  of  a  locust  or 
grasshopper. 


NOMENCLATURE. 


57 


Fig.  85. 
Young  Leaf  Insect.     {Compare  Figure  49.) 


studied.  lu  all,  some 
two  to  three  hundred 
thousand  kinds  of  insects 
have  been  classified.  Each 
of  these  has  received  a  dis- 
tinctive name. 

In  the  first  place,  all 
insects  that  are  almost  ex- 
actly alike,  that  can  breed 
tog-ether,  and  that  may 
have  been  descended  from 
the  same  pair  of  insects 
during"  recent  generations 
are  said  to  belong  to  the 
same  species;  species  in 
fact  are  kinds  of  insects. 
A  number  of  species 
which  are  similar  in  all 
but     colouring    or     other 


A  caterpillar  is  the  larva  of 
a  butterfly  or  moth. 

A  gritb  applies  to  the  larvii 
of  Coleoptera  or  llymenoptera. 

A  maggot  is  the  larva  of  a  fly 
[JJiptera) . 

A  chrysalis  is  the  pupa  of  a 
butterfly  or  moth  only. 


Nomenclature. 

Insects  have  been  systemati- 
cally studied  during  the  last 
two  centuries  and  only  a  small 
part  of  living  insects  have  been 
examined.  In  India  a  very 
small  part  of  the  insect  fauna 
is  known,  though  some  of  the 
very   common   ones   have  been 


Fig.  86. 


Wood-horing  Beetle,     a,  Gruh  ;  b,  Pujm ;  c,  Female; 
A,  Male;  e,  Tunnels  in  ivood. 


5S 


CLASSinCATlON   AlCD   NOMENCLATURE. 


unimportant  characters  are  said  to  form  a  genus.  Each  genus  and 
each  species  receive  names.  Thus  tlie  Indian  locusts  belong  to  one 
genuS;  Acridium.  Of  these  one 
species  is  Acriduim  peregrinum, 
another  is  Acridium  succinctum, 
and  so  on.  Each  species  thus  has 
a  double  name,  one  for  the  species, 
another  for  the  genus. 

These  names  are  generally  com- 
posed of  Greek  or  Latin  words. 
In  old  days  every  one  in  Europe 
knew  these  languages,  and  so 
these  names  could  be  understood 
by  scientists  of  all  the  Euro- 
pean nations,  whether  they  were 
French,  German,  English,  etc. 
Originally  these  names  had  definite  meanings,  but  the  number  of 
known  species  is  now  so  great  that  almost  any  word  is  used  put  into  a 
Latinised  form. 

At  the  end  of  every  scientific  name  there  is  an  abbreviation  for  the 
name  of  the  person  who  first  described  and  named  that  insect ;  thus  the 
full  title  of  the  North-West  locust  is  Acridium  peregnmim,  Oliv.  '  Verc 
grinum '  is  the  name  given  to  the  species  by  Oliver,  and  as  it  resembles 
other  insects  of  the  genus  Acridium  it  is  put  into  that  genus. 


Fig.  87. 
Mulherry  free  Boring  Beetle. 


Fia.  88. 
Grnh  of  Mvlhevry  Borinci  Bedle. 


This  system  of  naming  insects  is  absolnloly  necessary  for  syslema- 
tists  and  scientists;  it  is  liowever  very  confusing,  as  entomologists 
are  not   agreed   as  to  the  original   name   given    to   each   insect.     Two 


INSECT   NAMES. 


59 


entomologists  may  find  the  same  species  in  different  places  and  both  will 
describe  and  name  it,  using-  different  names.  Both  names  cannot 
be  \ised,  and  it  is  now  agreed  that  the  name  which  was  first  published 
shall  be  used.  This  again  causes  great  confusion,  as  people  cannot 
ao-ree  which  was  the  name  first  used. 

It  can  be  seen  that  the    naming  o£  insects  is   a  very  difficult  mat- 
ter;  there   are,   for   instance,   some    2,500    species  of  grasshoppers    and 
locusts     described;    of    these 
perhaps   400    are    known    to 
live   in   India,  but  there  are 
probably  also    in  India   some 
400  more  which  have  not  yet 
been  described;   it  is  no  easy 
matter  to  know,  first,  if  any 
Indian     grasshopper     is     the 
same    as    one     of     the     400 
already    described    in    India; 
second,    whether    it     is     the 
same    as    one    of    the    2,500 
described  from    all    parts   of 
the  world;   or  third,  whether 
it  is  new;  if  it  is  new,  that 
is,  not  yet  described,  it  must 
be  described  as  a  new  species 
and  perhaps  as  a  new  genus. 
As   locusts  and    grasshoppers 
make  up   only    one    of    over 
200    families    of    insects,    it 
is   clear   that   it  is    no    easy 
matter    to   use   the   scientific 
names     of    insects    correctly. 

In  this  book  scientific  names  are  not  much  used;  it  is  as  easy  to  learn 
about  the  Bombay  locust  as  it  is  about  Acridium  sicccincitcm,  L.  Persons 
who  see  an  insect  in  the  field  and  know  that  it  is  Pentadact^/lortJiopteroi' 
des  vigintioctonigropuncttdomaculata  N.  are  apt  to  forget  whether  it  is  a 
grasshopper  or  a  beetle  and  whether  it  is  injurious  or  not.  No  good 
is  done  by  hurling  scientific  names  at  an  insect  in  the  field.  It  is  far 
more  important  to  bo  able  to  recognise  a  cockchafer,  to  know  that  its 
grub  lives  in  the  ground  and  eats  roots,  and  to  know  that,  if  one  is  found, 
others  are  likely  to  be  there  and  should  Ije  destroyed  before  they  lay 
eggs.     As  far  as  possible,  plain  English  names  have  been   used  for  the 


Fio.  89. 
Caterpillar,  Pupa  and  Moth. 


60  CLASSinCATION    AND    KOMENCLATUfet. 

insects  mentioned  in  this  book.  To  avoid  confusion  and  to  assist 
reference,  I  have  put  as  a  footnote  the  register  numbers  of  the  oflicial 
collection,  the  name  of  the  family  and  what  I  believe  to  be  the  correct 
designation  of  the  insects  referred  to  in  nearly  all  cases. 


Part  11. 


PREVENTIVE  AND  REMEDIAL  MEASURES. 


CHAPTER  V. 

ORIGIN  OF  INSECT  PESTS. 

IT  is  well  known  that  the  natural  increase  of  any  insect  would  be 
very  large  if  the  restraining  checks  were  removed.  It  is  also  true  that 
a  species  rarely  becomes  so  abundant  as  to  cause  serious  damage  to  crops. 
We  may  here  shortly  discuss  the  causes  which  lead  to  the  undue  increase 
of  an  insect,  so  that  it  becomes  a  pest. 

In  this  book  we  propose  to  record  about  one  hundred  species  of 
herbivorous  insects  wliich  have  become  injuriously  abundant  in  recent 
years ;  tliis  is  a  small  fraction  of  the  herbivorous  insects  common  in  the 
plains,  which  can  and  do  feed  upon  crops.  Why  do  not  the  larger  part  of 
these  insects  also  become  abundantly  destructive  ?  There  is  no  answer  to 
this  question,  nor  has  it  ever  been  answered  in  any  country ;  we  can  but 
dimly  see  the  laws  which  govern  the  increase  of  animal  life,  and  in  this 
limited  space  we  can  but  discuss  some  of  the  most  obvious  laws  and 
phenomena  which  a  close  study  of  nature  presents  to  us. 

In  the  first  place,  let  us  examine  the  rate  of  increase  of  an  insect. 
A  single  female  of  one  of  our  commonest  moths  lays  over  500 
eggs.  Of  these  actually  200  have  been  reared  to  moths  again  under 
artificial  conditions ;  these  produce  50,000  eggs,  since  roughly  half 
are  females.  Of  these  again  we  rear  30,000  moths  which  produce 
5,000,000  eggs.  This  is  the  rate  of  increase  based  on  the  actual  ratio 
that  live  in  captivity.  We  see  that  the  increase  of  one  moth  in  three 
generations  is  vast,  equivalent  approximately  to  ten  large  and 
devastating  swarms  of  caterpillars.  This  is  not  a  peculiar  case,  just  one 
taken  at  random  and  well  within  the  limits  of  any  herbivorous  insect 
investigated  in  India.  We  can  see  then  that  every  moth  feeding  upon  a 
crop  plant  should,  if  there  were  no  checks,  produce  a  vast  progeny. 
Clearly  also  the  checks  are  very  efiicient  since  this  does  not  occur.  The 
checks  upon  the  increase  of  insects  may  be  roughly  said  to  be  climate^ 
lack  of  food  J  enemies. 

Climatic  checks  are  of  great  importance,  and  we  cannot  pretend 
yet  thoroughly  to  understand  them.  Most  insects  become  torpid  with 
cold  and  hibernate  (lie  dormant)  for  some  three  months.  Not  only  does 
this  stop  increase  at  this  time  but  the  hibernating  insect  is  exposed  to 
many  dangers  during  this  period — dangers  it  cannot  guard  against. 
Probably  a  very  large  percentage  do  not  survive  the  winter.     There  is 


64  ORIGIN    OF    INSECT    PESTS. 

then  the  period  o£  dry  lieat,  which  is  to  many  equally  a  period  of  rest 
during  wliich  their  enemies  are  especially  active.  Finally^  there  are  four 
months  of  suitable  weather,  during-  which  they  can  increase ;  even  this  is 
probably  not  entirely  favourable  as  it  is  likely  that  excessively  heavy  rain 
and  wind  storms  do  much  to  kill  moths  and  flying  insects. 

The  lach  of  food  is  another  powerful  cause ;  as  a  rule,  plants  grow 
vigorously  during  the  rains,  many  grow  during  the  cold  weather,  after 
which  a  great  proportion  of  the  vegetation  dies  down.  An  insect  feeding 
on  a  plant  that  grows  only  in  the  rains  has  but  a  few  months  in  which 
to  multiply;  if  it  can  also  feed  upon  cold  weather  plants  it  has  some 
months  longer,  provided  it  is  not  numbed  by  cold,  and  finally  it  has  no 
food  for  some  months  of  dry  heat. 

The  third  great  check  is  due  to  enemies  j  these  include  the  parasites, 
the  predatory  insects,  the  birds,  bats,  etc.  As  soon  as  an  insect  becomes 
abundant,  these  attack  it  and  reduce  its  numbers  (see  page  268). 
Fungoid  and  bacterial  diseases  are  also  operative  in  insects  as  they  are  in 
man  and  domestic  animals. 

In  the  jungle  or  forest,  we  find  that,  on  the  whole,  these  causes 
acting  against  the  naturally  large  ratio  of  increase,  tend  to  preserve  an 
even  level  for  all  insects ;  what  we  may  call  the  balance  of  life  is  main- 
tained, and,  neglecting  small  variations,  in  nature  the  numbers  "bf  each 
species  are  more  or  less  constant  over  long  periods.  Where  man  has  not 
interfered,  insects  do  not  become  destructively  abundant ;  there  are  excep- 
tions, of  course,  but  then  the  balance  adjusts  itself  very  swiftly.  We 
are,  however,  not  dealing  with  the  jungle  where  nature  reigns,  but  with 
artificially  maintained  areas  of  cultivation.  There  man  has  upset  the 
original  conditions  in  very  definite  ways  for  which  he  pays  the  penalty. 

Firstly,  the  balance  of  life  is  commonly  upset  by  the  new  forms  of 
life  which  are  introduced  by  man  himself  or  which  come  with  him.  The 
introduction  of  the  Gipsy  Moth  to  the  United  States  let  loose  an  insect 
whose  increase  was  so  enormous  that  as  much  as  four  lakhs  were  spent 
yearly  in  one  State  in  checking  it.  The  disastrous  results  that  followed 
the  introduction  of  the  Indian  mongoose  to  the  West  Indies,  of  the  rabbit 
to  Australia,  of  ferrets,  stoats  and  weasels  to  New  Zealand,  of  the  sparrow 
to  the  United  States,  and  of  the  Indian  myna  to  the  Hawaiian  Islands  are 
examples  of  the  manner  in  which  the  balance  of  life  is  upset  by  the^  intro- 
duction of  new  forms. 

Secondly,  we  may  refer  to  the  interference  with  the  climate  caused 
by  the  changes  made  upon  the  earth's  surface  by  man  ;  such  a  change  as 
the  destruction  of  the  forests  is  the  most  obvious  case,  leading  to  profound 
modifications  in  the  climatic  conditions  of  large  areas. 


THE    BALANCE    OF    LIFE.  65 

Thirdly,  the  plaut  life  may  be  entirely  altered.  This  is  by  far  the 
most  obvious  cause  and  deserves  separate  discussion. 

Lastly,  the  interrelations  of  the  fauna  are  deliberately  upset  by  man 
in  shooting  insectivorous  birds,  in  checking'  beneficial  insects  and  in 
making"  the  conditions  unsuitable  to  useful  insect-eating  animals. 

The  last  two  are  the  really  important  causes  that  affect  insects 
directly.  In  cultivated  areas,  we  grow  large  numbers  of  the  same  plant 
side  by  side;  any  insect  that  can  feed  upon  a  cultivated  crop  finds 
abundant  food,  has  not  to  search  for  it,  and  can  readily  lay  its  eggs  in  one 
place.  Instead  of  searching  through  the  jungle  for  the  particular  plant 
she  requires,  a  female  moth  emerges  in  a  field  of  that  plant,  finds  a  mate 
at  once  and  can  readily  lay  eggs ;  she  is  not  exposed  to  enemies  in  her 
flights  to  find  a  mate  or  in  her  endeavours  to  find  sufiicient  food-plants  on 
which  to  lay  her  eggs.  Not  only  does  man  grow  larger  areas,  but  he 
grows  the  plants  at  seasons  of  the  year  when  food  is  otherwise  scarce ; 
the  crops  grown  under  irrigation  in  the  hot  dry  weather  help  many 
insects  over  a  critical  time  and  so  give  them  an  additional  opportunity  of 
breeding  and  multiplying. 

Further,  plants  grown  under  somewhat  artificial  conditions  have  not 
the  same  vigour  to  resist  pests  as  plants  growing  wild  in  the  jungle. 
Few  crop'  plants  are  grown  where  they  naturally  thrive ;  in  the  jungle 
there  is  competition,  there  is  a  struggle  for  life  and  only  strong  healthy 
plants  in  good  vigour  can  live ;  in  cultivation  plants  are  kept  alive  by 
stimulation,  are  grown  in  soil  that  does  not  suit  them,  are  "  domesticated " 
and  have  not  the  vigour  that  especially  resists  the  plant  parasites.  How 
seldom  we  see  a  wild  plant  attacked  by  scale  insects  or  plant  lice?  A 
wild  plant  has  the  vigour  to  resist,  to  make  itself  distasteful  and  to 
out  arrow  the  disease. 

In  addition  to  helping  the  increase  of  insects  by  the  artificial  manner 
in  which  he  grows  his  crops,  man  does  so  also  by  checking  the  birds  and 
other  predators  which  check  insects.  These  include  birds,  lizards,  bats, 
predatory  and  parasitic  insects  and  the  like.  They  are  discussed  in  detail 
elsewhere,  but  we  can  see  that  our  artificial  conditions  upset  this  part  of 
the  balance  of  life  and  so  give  opportunities  for  the  abnormal  increase  of 
insects. 

If  we  consider  this  question  as  a  whole,  we  can  dimly  see  that  every 
now  and  then  the  checks  which  are  usually  operative  may  temporarily  be 
suspended,  so  that  we  get  a  vast  increase  in  the  numbers  of  some  common 
insect,  i.e.,  of  an  insect  which,  if  abundant,  probably  destroys  a  crop. 
Then  we  have  an  outbreak  of  a  '^pest,''  a  perfectly  natural  phenomenon 
due  to  causes  which  man  himself  brings  about,     In  nature,  and  generally 


66  ORIGIN  OF  INSECT  PESTS. 

in  our  cultivated  areas,  the  increase  of  insects  is  automatically  and  natur- 
ally checked ;  at  times  it  is  not  checked  in  our  artificial  surroundings, 
whereby  we  suffer. 

These  facts  require  to  be  borne  in  mind  in  considering-  our  pests  and 
the  manner  in  which  they  appear.  An  outbreak  of  an  insect  pest  is  not 
due  to  supernatural  phenomena,  nor  is  it  wholly  due  to  au  east  wind,  last 
yearns  flood,  late  rains  or  other  causes.  Cultivators  commonly  believe 
that  the  sudden  appearance  of  a  pest  is  more  or  less  supernatural,  and  for 
that  reason  not  capable  of  treatment;  it  is  no  more  supernatural  than 
when  a  bullock  gets  into  a  young  crop  and  eats  it,  only  we  can  trace  the 
bullock  and  cannot  always  trace  the  insect  pest.  Above  all  we  must 
remember  that  our  insect  pests  are  always  with  us,  but  not  always 
abundant.  Insect  j)ests  do  not  appear  suddenly  from  nothing ;  they  are 
the  insects  common  throughout  the  plains,  which  under  a  certain 
combination  of  circumstances  increase  sufficiently  to  do  damage.  No 
conditions  of  manuring,  irrigation  or  the  like  can  produce  them,  but 
suitable  conditions  can  enable  them  to  increase  beyond  their  natural 
limits  and  turn  them  into  a  pest. 

As  can  readily  be  seen,  the  conditions  which  govern  this  very 
delicate  balance  of  life  are  extremely  complex,  and  we  cannot  always  see 
what  causes  have  led  to  a  particular  result.  The  preventive  measures 
discussed  in  the  next  section,  as  well  as  one  simple  method  of  encouraging 
parasites  (see  page  271),  ai'e  based  upon  our  knowledge  of  these  causes.  A 
little  consideration  further  helps  us  in  some  cases  to  anticipate  an  outbreak 
of  an  injurious  insect,  on  perfectly  simple  reasoning.  An  entomologist 
who  sees  hundreds  of  the  moths  figured  on  page  188  flying  in  March,  as 
is  commonly  the  ease,  will  know  that,  if  sufficient  wild  plants  are  not 
available,  the  crops  will  be  attacked ;  he  will  also  know  that  there  must 
have  been  abundance  of  the  caterpillars  of  this  moth  before  the  cold 
weather,  and  that  probably  they  might  then  have  been  destroyed  either 
in  the  crops  or  by  more  careful  attention  to  clearing  away  weeds  on  waste 
strips  and  headlands. 

Again,  if  we  see  a  swarm  of  caterpillars  in  the  fields  or  in  uncultivated 
land,  it  is  worth  while  ascertaining  whether  they  are  extensively  attacked 
by  parasites  or  not ;  if  we  see  many  flies  (fig.  325)  or  ichneumons  (fig.  323) 
among  these  caterpillars  or  laying  eggs  on  them  (a  matter  requiring  but 
little  observation),  it  is  probably  advisable  not  to  destroy  these  caterpillars 
unless  they  are  doing  very  great  injury  ;  if,  however,  we  find  no  parasites 
or  only  small  numbers,  we  must  use  every  endeavour  to  destroy  them  or 
prevent  them  becoming  pupae,  as  the  next  outbreak  will  be  a  very  large 
one,     An   agriculturist   who  understands  something   about  these  moths 


ARTIFICIAL    USB    OF    CHECKS.  67 

will  see  ways  in  which  he  can  turn  his  knowledg-e  to  good  use  either  in 
preventing  the  occurrence  of  such  pests  or  in  checking  them. 

A  subject  that  has  unfortunately  attracted  general  attention  is  the 
fascinating  one  of  using  one  insect  to  destroy  another.  "We  know  that 
there  are  parasites,  predators  and  the  like  which  destroy  insect  life ;  the 
inference  is  that  we  should  be  able  to  check  all  our  pests  by  their  means. 
Entomologists  have  devoted  great  attention  to  this  point,  with  an  almost 
complete  record  of  failure.  In  one  instance,  under  very  peculiar  condi- 
tions, success  was  attained,  a  ladybird  beetle  being  introduced  to 
destroy  a  virulent  insect  pest.  The  particular  conditions  in  this  case 
were  that  the  pest  was  newlij  introduced,  had  no  enemies  in  the  locality 
to  which  it  was  introduced,  and  could  be  traced  to  the  country  whence  it 
came.  It  was  not  difficult  to  obtain  from  that  country  the  beetle  that 
there  preyed  on  it,  and  liberate  it  where  it  could  find  its  accustomed 
prey,  which  was  the  only  insect  it  recognised ;  it  utterly  destroyed  the 
pest,  partly  because  it  had  no  other  food  and  partly  because  it  had  no 
enemies  in  that  place.  Evidently  this  could  be  repeated  with  some 
chance  of  success,  but  only  in  the  case  of  newly  introduced  pests.  Our 
pests  in  India  are  probably  of  long  standing ;  they  have  enemies  here,  but 
the  fluctuations  in  the  balance  of  life  occasionally  enable  them  to  be 
destructive.  No  parasite,  no  enemy  will  entirely  destroy  an  insect  that 
is  established  throughout  India,  and  there  is  no  advantage  to  be  gained 
by  introducing  fresh  parasites.  There  is  also  no  ground  for  believing  that 
in  the  near  future  we  shall  be  able  to  artificially  employ  fungoid  and 
bacterial  diseases  in  the  destruction  of  insect  pests ;  they  appear  to 
require  special  climatic  conditions  {e.g.,  very  moist  heat),  and  this  places 
the  matter  beyond  our  control. 

What  is  of  extreme  practical  importance  is  to  encourage,  not 
particular  parasites  that  are  already  doing  their  utmost  under  conditions 
beyond  our  control,  but  birds  which  will  destroy  any  insect  that  becomes 
too  numerous.  Birds  are  the  fluctuating  check  on  insect  life,  the  safety 
valve  as  it  were  ;  they  congregate  where  they  lind  insects,  regardless  of 
their  species  or  habits,  and  constantly  consume  the  superfluous  and 
superabundant  insect  life.  We  can  encourage  birds  by  planting  trees,  by 
letting  them  take  a  not  too  excessive  toll  from  the  fields ;  and  every' 
insectivorous  kind  means  a  large  diminution  in  our  pests.  We  cannot 
as  yet  equally  encourage  other  beneficial  organisms,  but  must  rely  on  our 
own  efforts  to  check  the  superabundant  insect  life  that  destroys  oui'  crops. 


CHAPTER  VI. 

PREVENTIVE  AND  REMEDIAL  MEASURES. 

PREVENTION  is  better  than  cure,  costs  less  to  carry  out  and  forestalls 
the  loss  of  crop.  Most  measures  of  this  kind  depend  upon  a  kind  of 
commonsense  that  is  practically  non-existent  in  India  and  rare  anywhere. 
It  is  difficult  to  prove  the  value  of  preventive  measures,  which  depend 
solely  upon  a  thorough  knowledge  of  the  conditions  under  which  insects 
live  or  upon  reiterated  experience.  If  our  pests  come  regularly  and  at 
definite  times,  the  value  of  such  measures  can  be  clearly  demonstrated ; 
but  since  insects  are  not  so  accommodating  and  come  at  haphazard,  it  is 
difficult  to  bring  them  within  range  of  actual  experiment.  There  are 
several  simple  precautions  which  are  sufficiently  obvious  to  any  one  who 
practises  agricultm-e  intelligently ;  they  are  also  general  in  their  appli- 
cation and  should  form  part  of  every  agriculturist's  stock  of  maxims. 
Clean  culture  is  important ;  many  insects  breed  on  common  weeds, 
become  abundant  and  are  driven  by  lack  of  food  to  attack  crops.  That  is 
a  common  way  in  which  many  insects  become  pests.  An  herbivorous 
insect  that  increases  beyond  natural  limits  will  attack  a  crop  on  which  it 
can  feed,  and  it  is  folly  to  encourage  pests  by  growing  their  wild  food- 
plants  within  reach  of  cultivation.  Weeds  are  always  a  source  of  danger 
and  do  no  good.  This  applies  equally  to  the  strips  of  grass  that  border 
on  fields,  to  waste  lands,  jungle,  etc.  Good  grass  is  safe  and  brings  no 
pests ;  mixed  weeds  and  low  vegetation  should  be  replaced  by  grass  or 
kept  down.  The  ideal  cultivator  allows  no  weeds  or  plants  to  grow 
other  than  crops  and  grass. 

Another  precaution  consists  in  removing  crop  plants  when  the  crop 
is  harvested.  Old  cotton  plants  afford  food  to  cotton  pests,  thus  helping 
them  through  critical  seasons  when  food  is  scarce.  Juari  stubble  har- 
bours the  moth-borer  and  enables  it  to  hibernate.  A  crop  plant  that  has 
yielded  should  be  removed  and  not  allowed  to  breed  pests  after  it  is 
useless.  It  is  at  all  times  necessary  to  weed  out  dead  and  dying  plants 
from  a  crop  and  burn  them.  The  brinjal  grower  pulls  out  the  plants 
attacked  by  stem-borer  and  leaves  them  in  the  field.  If  he  burnt  them, 
he  would  destroy  his  pest  and  check  its  increase ;  as  it  is  the  calerpillar 
completes  its  metamorphosis,  comes  out  as  a  moth,  lays  its  hundred  eggs 
and  the  loss  of  plants  steadily  increases.  The  same  thing  applies  to  all 
refuse  plants,  dead  wood,  rotting  fruit,  etc.  Even  weeds  should  be 
removed  when  they  are  pulled  up  and  not  allowed  to  rot  in  the  field.  No 
vegetable  matter  should  ever  be  allowed  to  decay  in  a  field  or  anywhere 


MIXED     CROPS.  69 

but  in  a  proper  compost  heap.  The  useless  cotton  bolls  not  worth  pick- 
ing breed  cotton  pests  and  do  much  harm;  they  should  be  removed 
periodically  and  carefully  burnt  with  all  their  inhabitants.  He  who 
leaves  fallen  mangoes  to  rot  where  they  fall  should  not  be  surprised  if 
his  sound  mangoes  are  attacked  by  pests  bred  in  the  fallen  ones. 

Rotation  of  crops  is  a  practice  of  some  value  and  is  more  valuable 
the  larger  the  area  rotated.  Keeping  two  acres  side  by  side  in  sorghum 
and  cotton  alternately  does  not  help  matters  so  far  as  insects  are  con- 
cerned ;  but  the  rotation  of  large  blocks  of  land  in  alternate  crops  does 
much  to  check  pests.  In  rare  cases  it  is  possible  to  check  a  pest  by  not 
growing  its  food-plant  for  a  year  or  longer,  substituting  other  crops. 

The  practice  of  growing  mixed  crops  has  a  profound  influence  upon 
insect  life  and  is  generally  most  beneficial.  Growing  crops  in  separate 
blocks  which  might  be  mixed  and  grown  in  alternate  rows  is  a  direct 
incentive  to  insect  attack,  and  the  mixed  cultivation  of  the  Indian  culti- 
vator might  well  be  followed  in  other  countries  where  pests  are  rife. 
Mixed  crops  approximate  to  natural  conditions  and  discourage  the 
increase  of  insect  pests.  Cotton  grown  with  tur,  urd  or  maize  suffers 
less  from  insect  pests  which  do  not  so  easily  find  the  cotton  j  the  moth 
has  to  search  for  her  food-plants,  and  in  so  doing  runs  risks  of  enemies ; 
the  caterpillars  cannot  simply  crawl  from  plant  to  plant,  but  must  move 
over  the  ground  with  the  risk  of  being  snapped  up  by  ground  beetles, 
frogs  or  birds.  The  mixed  crop  is  a  great  safeguard,  though  the  cultivator 
does  not  know  the  reason  but  benefits  by  the  accumulated  experience  of 
distant  ages.  Opposed  to  the  mixed  crop  is  the  small  plot  of  any 
single  crop.  A  small  area  of  a  single  crop  in  a  large  area  of  other  crops 
is  an  inducement  to  insects  to  cluster  in  that  small  plot,  and  destroy  it. 
Insects  which  are  harmless  when  scattered  over  one  thousand  acres  are 
extremely  destructive  in  a  small  plot,  and  probably  devour  it  all.  Nothing 
is  more  fatal  than  to  grow  a  small  area  of  a  plant  j  it  is  not  the  small 
plot  but  the  relative  area  which  matters ;  if  a  crop  is  grown  in  its  due  pro- 
portion, say  one  thousand  acres  in  five  thousand,  it  may  be  broken  up 
into  small  plots,  but  the  insects  are  scattered  over  the  district ;  but  if 
there  is  only  one  plot  of  say  ten  acres  in  that  five  thousand  acres,  then 
that  plot  is  liable  to  suffer.  Many  promising  experimental  cultivations 
of  crops  suffer  because  insects  gather  in  that  one  little  plot.  If  the 
experiment  had  been  on  a  larger  scale  or  if  the  pests  had  been  checked, 
the  experiment  would  have  had  a  better  chance  of  giving  true  results.  If 
one  grows  plants  under  such  conditions,  one  must  expect  abnormal  results 
and  take  measures  accordingly. 

Much  encouragement  is  given  to  pests  by  the  promiscuous  growth 
of  plants  that  harbour  pests  at  seasons  when  the  crops  are  not  available* 


70  tllEVENTIVE   Aisri)    REAtEDlA-L    MEASUllfiS. 

Bhindi  is  a  plant  that  should  be  rigidly  excluded  from  cotton  areas,  as 
should  hibiscus,  the  roselle  hemp  [ambadi,  skerria,  etc.),  the  holly-hock 
and  a  few  other  malvaeeous  plants.  If  grown  they  should  be  grown  only 
where  cotton  is  also  growing  so  as  to  draw  off  the  pests  from  it.  There 
is  probably  a  large  field  for  the  prevention  of  pests  in  this  way,  but  we 
have  not  yet  obtained  the  requisite  knowledge  of  Indian  insects  to  be 
able  to  make  use  of  it.  Equally  we  do  not  yet  know  how  to  use  trap 
crops  to  the  best  advantage.  Trap  crops  are  crops  grown  to  lead  the 
pests  off  from  the  valuable  crop  plants.  The  cultivator  who  sows  mixed 
seeds  in  an  irrigated  plot  of  land  and  pulls  out  half  of  the  plants  with 
caterpillars  on  has  unconsciously  used  a  trap  crop  and  saved  his  really 
valuable  plants.  If  he  went  one  step  further  and  destroyed  those 
caterpillars  and  plants  he  Avould  do  still  more  good  and  use  his  trap  crop 
intelligently.  There  are  two  ways  in  which  trap  crops  can  be  used ;  we 
can  sow  an  early  small  crop  for  the  insects  to  eat,  sowing  the  bulk  of  the 
field  later  and  destroying  the  early  crop  with  the  insects  on  or  leaving'  it 
until  the  main  crop  is  well  established ;  we  can  sow  two  crops  together, 
one  a  valueless  crop  to  act  as  a  bait  for  insects  and  which  grows  only  so 
long  as  it  serves  its  purposes,  being  destroyed  as  soon  as  it  is  full  of  pests 
or  as  soon  as  it  interferes  with  the  growth  of  the  main  crop.  Neither 
method  has  been  adequately  tried  in  India,  though  the  latter  is 
unconsciously  done  by  cultivators,  and  in  rare  cases  deliberately;  the 
method  deserves  to  be  far  more  widely  tried  on  an  experimental  scale. 

The  most  valuable  of  our  preventive  measures  after  mixed  crops  is 
the  practice  of  killing  whatever  caterpillars  are  found  in  crops,  when  they 
are  few.  If  cultivators  realise  that  caterpillars  are  not  harmless  and  that 
anything  that  eats  his  crop  may  become  a  serious  pest,  and  if  he  would 
but  kill  these  stray  insects  from  the  first,  the/  would  not  multiply  to 
the  extent  that  they  now  do.  At  present  the  first  brood  of  insects  is 
never  killed,  the  second  is  larger  and  does  more  harm ;  the  third  eats  the 
whole  crop  or  perhaps  emerging  next  season  after  hibernation  wipes  out 
the  young  crops.  If  the  first  brood  were  checked,  there  would  be  no 
second  or  third  brood  and  no  loss  to  the  crop.  Such  a  procedure  is  far 
more  possible  in  India  than  in  other  countries ;  the  process  of  picking  off 
caterpillars  is  one  that  is  not  essentially  different  from  the  process  of 
laborious  hand-weeding  and  can  often  be  done  at  the  same  time^  It  is 
as  natural  and  feasible  as  weeding,  only  it  has  never  become  part  of 
established  usage.  Caterpillars  are  always  safe  things  to  kill,  though 
other  insects  are  not,  and  it  is  from  caterpillars  that  most  of  the  harm 
to  agriculture  comes. 

A  common  practice  which  helps  crop  pests  is  that  of  letting  stray 
crop  plants  grow  either  at  the  wrong  season  or  in  the  wrong  field.     Stray 


liEMEDltiS.  1 1 

plants  of  maize,  ot  bliindi,  of  juari,  of  beans,  of  any  erop  plants  should 
never  be  g-rown  in  the  fields  at  any  time.  They  eome  up  from  stray  seed 
and  are  allowed  to  grow  freely,  perhaps  in  border  strips  ;  they  harbour 
pests  and  help  them  over  critical  periods  when  food  is  scarce ;  all  such 
plants  should  be  pulled  up  unless  grown  for  a  distinct  purpose. 

A  precaution  that  might  be  used  far  more  freely  is  that  of  trenching, 
either  to  isolate  an  infested  plot  or  to  protect  an  uninfested  one  from  a 
neighbouring  infested  one.  When  caterpillars  are  abundant,  they  eat  the 
plant  they  are  on  and  move  away  to  others ;  rarely  they  move  in  a  body, 
usually  singly ;  the  owner  of  an  infested  plot  is  doubtless  glad  to  see 
them  go,  but  his  neighbours  should  certainly  make  trenches,  which  need 
not  be  more  than  a  few  inches  deep  with  sloping  sides.  Such  trenches 
do  much  to  isolate  pests  which  cannot  fly,  especially  caterpillar  plagues  ; 
these  caterpillars  often  become  restless  and  move  about  at  a  special  period 
of  the  day,  falling  very  soon  into  the  trenches ;  large  numbers  can  then 
be  killed  in  a  very  simple  manner. 

Another  simple  precaution  on  small  holdings  is  the  common  hen,  an 
indefatigable  insect  hunter ;  turkeys  and  guinea-fowls  are  equally  good 
but  rare.  The  hen  should  be  a  regular  part  of  a  ryot's  small  belongings, 
and  there  is  a  certain  justice  in  obtaining  fat  hens  from  the  insects  which 
eat  crops ;  it  is  necessary  to  give  the  hen  a  basis  of  other  food  and  not 
compel  her  to  a  purely  insect  diet. 

Whilst  there  are  many  methods  of  destroying  insect  life  on  a  small 
or  large  scale,  for  every  pest  there  is,  as  a  rule,  one  single  remedial  method 
which  proves  successful.  There  is  no  one  specific  capable  of  universal 
application,  no  "  cure-all,''''  no  patent  medicine  warranted  to  kill  every 
thing  from  fleas  to  locusts ;  if  there  is,  it  has  not  yet  come  within  the 
range  of  practical  science  and  is  made  only  to  sell  and  not  for  use. 

In  devising  remedies,  the  essential  things  are  a  knowledge  of  the 
habits  of  the  insect  and  a  full  understanding  of  the  local  conditions.  The 
habits  of  the  insect  vary  little  from  place  to  place,  and  their  variation  can 
be  predicted ;  but  local  circumstances  vary  from  village  to  village,  and 
what  is  effective  in  the  west  may  not  suit  the  east.  Thus  it  is  that  no 
remedies  can  be  given  for  such  a  pest  as  the  Rice  Stem  Fly ;  its  destruc- 
tion is  purely  a  matter  of  local  knowledge  and  of  so  altering  the  local 
agricultural  practices  as  to  baffle  the  insect ;  no  amount  of  scientific 
training',  no  remedies  from  the  most  advanced  scientific  nation  can  help 
us  in  a  case  like  this,  and  nothing  can  replace  the  local  knowledge  that, 
combined  with  a  knowledge  of  the  habits  of  the  pest,  at  once  points  to 
the  one  weak  spot  in  the  life  of  the  insect  and  adjusts  the  agricultural 
practices  accordingly.     That  is  the  essence  of  remedial  measures. 


n 


PllEVENTIVE   AND    REMEDIAL   MEASURES. 


The  remedies  described  below  are  those  so  far  tested  against  crop 
pests  in  India ;  they  have  been  laboriously  worked  out  after  many  failures 
and  in  the  face  of  many  difficulties ;  they  are  in  the  nature  of  sug'gestions, 
not  of  recommendations ;  such  suggestions  as  are  of  value  when  one  is 
face  to  face  with  a  pest  and  seeking  for  some  method  that  will  fit  in  with 
the  agricultural  conditions  and  with  the  ways  of  the  insect.  It  is  not  to 
be  supposed  that  any  one  can  read  these  pages  and  find  a  remedy  for 
every  and  any  pest.  At  best  they  are  suggestions,  which  are  the  pick  of 
the  methods  used  abroad  and  which  should  be  familiar  to  those  who 
experiment  with  crops ;  when  the  pest  comes,  some  method  may  be 
modified  with  practice,  which  will  perhaps  meet  the  case  and  give  good 
results.  No  remedy  is  of  the  slightest  use  unless  done  thoroughly  and 
with  the  full  determination  to  destroy  every  single  insect ;  if  one  could 
but  educate  the  ryot  up  to  that  feeling,  there  woiJd  not  be  a  pest  left 
in  densely  populated  India. 

The  simplest  method  is  to  pick  the  insects  off  the  plants  one  by  one 
and  Idll  them.  This  is  tedious,  but  satisfactory  and  effective.  As  stated 
above,  the  common  hen  is  perhaps  the  best  agent  for  the  purpose,  but  it 
is  a  remedy  far  more  suited  to  the  ways  of  India  where  holdings  are 
small,  time  is  plentiful  and  patience  unending  than  to  other  countries. 
Having  secured  the  insects,  there  is  no  difficulty  in  killing  them ;  a  pot 

of  hot  water,  a 
little  kerosene 

floating  on  a  pan 
of  water,  two  flat 
stones  or  a  fire  are 
all  equally  effec- 
tive. The  practice 
of  carefully  pick- 
ing off  caterpillars 
and  liberating 
them  at  a  distance 
of  say  one  hundred 
yards  from  the 
infested  plot  is 
not  only  ineffective 
and  futile  but  need- 
lessly cruel. 

An  improvement  on  hand-picking  is  a  bag,  a  basket  or  a  net.  The  bag 
is  a  most  valuable  instrument,  which  can  be  made  to  suit  all  circum- 
stances ;  with  a  width  of  12  feet  and  an  opening  3  feet  high,  it  sweeps 


Fig.  90. 

The  most  useful  bag,  loith  crost  bamboos  joined,  to  the  upright 

side  bamboos,  allowing  the  mouth  to  be  instantly  closed. 


BA(iS. 


78 


Fig.  91. 
Bag  with  two  upright  bamboos. 


large  stretches  of  grass  land ;  made  smaller,  say  ten  feet  by  two  feet,  it 
can  be  run  over  a  rice  crop,  over  wheat,  lucerne,  mustard,  etc. ;  smaller 

still,  it  is  attached 
to  the  frame  of 
bamboos  and  a 
single  man  draws 
it  between  the 
rows  of  crops, 
along  grass  strips, 
in  any  narrow 
places.  The  sim- 
plest pattern  has 
only  two  upright 
bamboos  to  hold 
open  the  sides;  a 
better  one  has  four 
bamboos,  the  two 
cross  ones  with 
projecting  handles, 

and  this  pattern  closes  up  automatically  at  the  end  of  each  sweep. 

The  depth  of  the  bag  depends  upon  its  use  ;  on  the  ground  it  may  be 

five  to  seven  feet  deep ;  but  should  be  shorter  for  use  on  crops  where 

has  to  sweep  over  the  plants  and  not  hang  too  much.     At  the  end  of  .each 

sweep  the  bag  is 

emptied  into  a  hole 

in     the     ground ; 

where  the   insects 

are  very  active,  it 

is    twisted    up    to 

crush     them    and 

then  opened.    (See 

page    288,   appen- 
dix A.) 

In    some    cases 

it  is    desirable   to 

smear    the    inside 

of    the    bag   with 

kerosene  oil,  heavy 

oil  or  tar  to  catch 

the  insects  as  they  fly  in ;  a  bag  which  is  slightly  moistened  with  kero- 
sene is  more  effective  because  the  kerosene  at  once  kills  many  insects. 


Fia.  'J-2. 
tSinall  bag  with  two  cross  bamboos. 


74  PfeHVIiNTlVE   AND   REMEDIAL   MEASUkES. 

The  basket  is  au  adjunct  to  hand-picking  when  it  is  possible  to  shake 
insects  off  tlie  plants  into  the  baskets  and  then  into  a  tin  of  kerosene  and 
water,  as  recommended  for  the  Red  Cotton  Bug  (page  104).  It  is  useful 
for  weevils  and  plant-feeding  beetles. 

The  net  takes  the  place  of  the  bag  in  some  cases,  as  when  catching 
the  Banded  Blister  Beetle.  What  is  required  is  a  bag  of  cloth  cut  as 
figured  (page  289)  and  sewn  up,  fastened  to  a  slij)  of  bamboo  that  is  lashed 
to  a  short  handle.  The  component  parts  are  very  simple,  the  net  easily 
made  and  it  does  good  service  in  gardens  and  small  holdings  where  such 
insects  abound.  The  practice  of  trenching  has  been  mentioned  above ;  it  is 
useful  when  one  is  catching  caterpillars  with  bags  as  many  escape  the  bag, 
wander  about  the  soil  and  fall  into  the  trench,  where  they  can  be  killed. 

Baits  of  cut  vegetation  are  useful  traps.  Many  injurious  insects  hide 
during  part  of  the  day  and  will  do  so  in  bunches  of  green  vegetation,  if 
these  are  laid  about  the  field.  The  bvmches  must  be  examined  periodically 
and  the  assembled  insects  shaken  off  into  hot  water  or  kerosene  and  water. 

Lights  are  useful  traps  for  a  few  insects,  especially  for  such  as  fly  at 
night.  Their  use  is  very  limited  and  fires  are  often  as  useful.  The  light 
trap  consists  of  an  ordinary  kerosene  lamp  hung-  over  a  broad  tray  contain- 
ing jaggery  and  water  or  water  with  a  film  of  kerosene.  Two  bent  pieces 
of  tin  serve  as  reflectors.  Cockchafers,  some  moths,  ants  and  a  few 
other  insects  are  generally  captured  and  the  trap  has  a  value  in  certain 
specific  cases. 

Smoke  is  a  deterrent  to  some  insects,  notably  such  as  attack  rice  and 
other  dense  crops  in  which  smoke  hangs  well.  The  smoke  of  a  few  fires 
will  not  kill  anything,  but  may  drive  out  such  an  insect  as  the  Rice  Bug 
at  a  critical  moment  when  the  grain  is  forming.  The  same  apphes  to 
cockchafers,  wliich  attack  grain  crops  just  as  they  are  ripening  and  which 
have  to  be  kept  off  until  they  die  naturally  or  until  the  grain  is  hard 
enough  to  resist  them. 

Cultivation  in  the  form  of  hoeing,  surface  ploughing,  etc.,  is  valuable 
chiefly  in  exposing  insects  to  birds  or  weather  and  is  less  a  remedial 
measure  than  a  preventive  of  attack ;  many  insects  that  eat  crops  harbour 
in  the  soil  or  descend  there  to  pupate ;  when  this  is  the  case  cultivation 
turns  out  many  to  become  the  food  of  mynas. 

Other  simple  remedies  are  discussed  above  under  "  Preventives."  A 
great  deal  can  often  be  done  to  check  a  pest  by  sacrificing  a  portion  of  the 
crops  that  is  first  infested  or  by  sacrificing  a  young  crop  with  the  insects 
on,  in  the  hope  that  a  second  crop  will  grow  up  free  of  the  insects.  A 
caterpillar-infested  crop  can  often  be  wisely  fed  off  to  cattle  or  cut  down, 
when  a  new  crop  is  likely  to  come  up. 


T 


CHAPTER   VII. 

INSECTICIDES   AND   SPRAYING. 

HE  essence  of  remedial  measures  is  to  attack  the  insect  directly,  to  make 
life  unbearable  to  him,  to  do  something  to  kill  him  or  to  drive  him 
away.  Such  methods  are  but  little  known  in  India ;  the  methods  of 
killing-  insects  on  a  larg-e  scale,  of  poisoning  acres  of  crops,  of  putting 
machinery  on  to  deal  wholesale  destruction,  do  not  occur  in  Indian 
agriculture.  At  most,  simple  methods  aimed  at  frightening  the  insects 
are  adopted  without  any  co-operation.  With  the  cultivator's  knowledge 
of  the  medicinal  value  of  plants,  it  is  somewhat  strange  that  plants  are 
not  used  as  insecticides  to  a  greater  extent.  The  juice  of  some  plants  is 
poisonous  to  insects,  as  is  the  infusion  of  the  dried  leaves  and  roots  or  the 
smoke  made  by  slowly  burning  the  dried  plant.  But  such  plants  are  little 
used ;  the  juice  of  Euphorbia  neriifolia  is  used  to  smear  toddy-palms  in 
Gujarat ;  the  leaves  of  iiim  are  believed  to  keep  off  insects  ;  the  infusion 
of  Adhatoda  vasica  or  of  Calotropis  is  used  in  irrigation  Avater,  as  are 
such  substances  as  castor  cake  and  khurasani.  Dekamali  gum,  asafcetida 
and  similar  drugs  enter  into  the  composition  of  such  mixtures  as  "  Gondal 
Fluid.'''  These  are  examples  of  the  use  of  plants,  but  they  rest  on  no 
basis  but  that  of  tradition  and  are  not  always  effective. 

It  is  singular  that  the  value  of  tobacco  infusion  does  not  appear  to 
be  more  widely  known ;  this  is  one  of  the  few  plants  used  as  an  insecticide 
in  Europe,  with  hellebore  {Veratrum  album) ,  pyrethrum  {Fyrethrum 
cinerariafolium) ,  quassia  [Picrana  excelsa).  From  the  use  of  these 
plants,  European  methods  of  checking  insects  have  developed  more  in 
the  direction  of  mineral  poisons,  a  branch  of  entomology  never  practised 
in  India.  At  the  present  time  far  more  reliance  is  placed  on  mineral 
poisons  than  on  vegetable  poisons,  and  even  the  Kentish  hop-grower  is 
abandoning  quassia  for  soft  soap.  This  is  true  also  of  America,  where 
the  use  of  purely  mechanical  methods  of  checking  insects  is  also  being 
developed  to  a  high  pitch.  It  has  yet  to  be  shown  how  far  "Western 
methods  are  applicable  in  the  East.  To  the  Western  mind  it  is  far 
simpler  to  poison  the  plant  by  spraying  on  lead  arseniate  than  it  is 
laboriously  to  pick  off  the  individual  caterpillars.  The  Eastern  mind  has 
not  yet  fully  grasped  the  idea  that  insects  could  be  or  should  be  killed  by 
hand-picking,   far  less  by  such  a  method  as  poisoning  the  plant  with 


76 


INSECTICIDES   AND   SPRAYING. 


arsenic.  If  there  is  any  value  in  the  use  of  insecticides  in  India,  their 
general  adoption  will  be  a  matter  of  slow  growth  that  must  first  be 
worked  out  on  the  experiment  farms. 

Insecticides  are  insect  poisons  and  act  in  two  ways.  There  are  those 
poisons  which  are  placed  upon  the  food  of  the  insect  and  Avhich  act  upon 
its  stomach,  just  as  medicines  and  poison  do  upon  human  beings.  These 
are  called  stomach  poisons  and  are  meant  only  for  internal  application. 


Fig.  93, 
Sand  S;prayer. 


If  caterpillars  are  destroying  the  leaves  of  a  valuable  plant  and  we  can 
put  poison  on  these  leaves,  the  caterpillar  eats  the  poison  with  the  leaves 
and  dies.  It  is  only  necessary  to  put  such  poison  on  the  leaves  of  crops, 
and  they  are  safe  from  all  caterpillars,  grasshoppers  and  other  insects 
which  eat  the  leaves.  There  are  also  many  insects  which  do  not  eat  the 
leaf,  but  which  suck  out  the  juice ;  these  feed  upon  the  sap  of  the  plant, 
not  on  the  leaf,  and  any  poison  on  the  leaf  never  reaches  their  stomachs. 
For  these  we  cannot  use  a  stomach  poison  as  we  cannot  poison  the  sap 
of  the  plant.  In  such  cases  we  must  use  poisons  which  kill  when 
the  insects  are  wetted  with  them.  These  poisons  are  known  as  contact 
poisons,  since  they  work  only  when  in  contact  with  the  skin  of  the  insect. 
If  a  colony  of  plant  lice  is  sucking  the  juice  of  a  cotton-plant,  we  cannot 
poison  the  juice,  so  we  throw  contact  poison  on  the  insects ;  all  are  ^killed, 
and  if  the  contact  poison  is  properly  made  the  plant  is  uninjured.  Both 
kinds  of  poisons  have  their  uses ;  we  can  poison  any  insect,  even  a  locust^ 
with  contact  poison  if  we  use  it  strong  enough,  but  it  is  better  always  to 
use  a  stomach  poison  for  a  biting  insect,  such  as  a  locust ;  whereas  for 
sucking  insects  we  can  never  use  a  stomach  poison  and  must  always  use  a 


SPRAYING   MACHINES. 


77 


contact  poison.  Stomach  poisons  are  in  general  far  cheaper ;  contact 
poisons  for  large  insects  require  to  be  very  strong  and  may  injure 
the  plants ;  stomach  poisons  should  always  be  used  if  possible,  but 
if  they  cannot  and  no  other  method  is  available,  we  must  use  a  contact 
poison. 

In  using  insecticides  we  must  have  a  method  of  putting  them  quickly 
over  a  large  surface  of  plant  or  insect.  The  value  of  insecticides  lies 
principally  in  the  rapidity  with  which  they  can  be  applied  to  a  large  area 
of  crop.  Insecticides  can  be  applied  in  liquid  form  with  water  or  as 
powder  mixed  with  lime,  dust,  flour,  etc.  An  insecticide  applied  as  powder 
requires  only  to  be  dusted  on  from  a  bag  and  this  is  the  simplest  method 
of  application.  A  liquid  insecticide  must  be  applied  as  a  fine  spray  or  mist 
that  wets  evenly  and  distributes  the  liquid  properly  over  the  whole  plant. 
For  this  work  the  spraying  machine  must  be  used. 

Spraying  machines  are  of  many  kinds,  all  designed  to  fulfil  the  one 
purpose  of  distributing  fluid  in  a  finely  divided  form  over  a  large  area  of 
plant.  The  simplest  pattern  is  the  tin  hand  sprayer  (figs.  93-94).  It 
consists  of  a  pump,  which  forces  air  out  of  a  fine  nozzle ;  the  compressed 
air  passes  over  the  opening  of  a  vertical  tube,  and  sucks  up  a  small  quantity 


Hand  Sprayer 


Fig.  94 

details  of  construction. 


of   the   insecticide   in   the   reservoir,  throwing  it    out  in  an  extremely 
fine  condition  in  the  jet  of  air.     The  whole  machine  is  made  of  tin  and 


78 


INSECTICIDES    AND    SPRAyiNG. 


wood,  costing"  under  two  rupees  to  prepare.  It  covers  very  little  ""round, 
however,  and  is  suitable  only  for  gardens  and  small  holdings.  It  is 
especially  useful  for  applying  contact  poisons  to  small  colonies  of  plant 
lice,  mealy  bugs  and  other  sucking  insects.  With  it  one  can  rapidly  and 
effectively  kill  such  insects  when  they  are  few.  It  is  not  adapted  to  larger 
areas,  but  as  a  check  on  incipient  diseases  it  is  invaluable  and  admirably 
suited  to  the  ryot.  If  this  were  in  general  use,  the  plant  lice  that  ravage 
cotton,  wheat,  mustard  and  other  staple  crops  could  be  nipped  at  the 
start  and  never  get  a  real  hold  on  the  crop. 

For  more  extensive  spraying,  a  larger  machine  must  be  emploj'ed, 
and  the  Success  Knapsack  Machine  ^  is  a  useful  pattern  obtainable  in 
India  at  a  cost  of  Rs.  46.  This  machine  holds  four  gallons  of  insecticide 
and  can  be  worked  on  the  ground  for  sj^raying  fruit  trees  or  on  the 
back  for  spraying  crops.  The  insecticide  is  pumped  through  the  rubber 
hose  out  at  the  nozzle  which    breaks   it   up   into  a  fine  mist.     Either 

of  two  nozzles  can  be  used, 
and  of  the  two  the  Bordeaux 
has  the  most  general  application 
and  value.  The  machine  is  built 
of  copper  and  brass,  which  are 
not  destroyed  by  insecticides.  It 
requires  to  be  kept  clean  and 
will  last  for  years  with  the 
occasional  renewal  of  the  rubber 
tube.  With  this  machine  from 
one  to  two  acres  of  crop  can  be 
sprayed  in  one  day,  using  two 
men  at  the  machine  and  others 
to  bring  water,  mix  insecticides, 
etc.  This  refers  to  cases  where 
continuous  spraying  is  required 
as  when  a  whole  crop  is  to  be 
sprayed  with  lead  arseniate. 
Where  individual  plants  here  and 
there  are  to  be  sprayed,  as  when 
afliis  is  attacking  cotton,  a  far 
larger  area  can  be  covered^daily. 
Larger  machines  are  used  to  apply  insecticides  to  fruit  trees,  to  special  crops 
and,  in  Europe  and  America,  to  field  crops.  It  is  unnecessary  to  discuss 
these  at  present  as  they  are  not  likely  to  be  used  for  field  crops  in  India. 
'  English  copies  of  descriptive  Jp^flet  are  available. 


Fio.  95. 
Success  Knapsack  Sprayer. 


LEAD    ABSENTATE. 


79 


They  can  be  obtained  on  wheels  to  work  by   hand,  on  carts  to  work  by 
£?asolene  en.^ines,  or  portable  outfits  on  the  plan  of  a  fire-engine  are  pre- 
pared which  work  by  steam  and 
cover  a  large  area  daily. 

The  choice  of  insecticides  for 
each  case  is  a  matter  requiring 
care.  The  principal  insecticides 
are  shortly  described  with  their 
uses.  The  formulae  for  prepar- 
ing these  mixtures  are  given  in 
Appendix  A,  page  283. 

Lead  Arseniate. 

This  is  practically  the  only 
useful  stomach  poison  available 
in  India,  and  no  other  is 
required.  Lead  arseniate  is  a 
form  of  arsenic  which  combines 
the  best  qualities  of  the  older 
stomach  poisons,  London  Purple, 
Paris  Green,  etc.,  with  qualities 
peculiar  to  itself.  It  is  a  white 
svibstance,  procurable  in  powder 
or  paste,  which  is  insoluble  in 
water,  harmless  to  plants,  and  easy  of  application  in  the  form  of  liquid 
or  powder.  It  has  a  considerable  power  of  resisting  rain  and  so  remaining 
on  the  plant  in  wet  weather,  and  its  white  colour  shows  up  on  the 
plants  to  which  it  is  applied.  It  is  poisonous  to  cattle  and  human 
beings  if  taken  in  any  but  a  very  small  dose,  but  it  can  be  applied  at 
such  strength  as  to  render  plants  poisonous  to  insects  though  not  to 
cattle.  Sprayed  on  to  plants  at  the  rate  of  one  pound  in  60  to  100 
gallons  of  water,  it  is  effective  as  a  poison  to  insects,  and  its  efficacy 
is  increased  by  adding  jaggery,  gur  or  molasses  and  lime.  The  usual 
mixture  is  one  pound  of  arseniate,  three  pounds  of  lime  and  six  pounds 
or  less  of  any  form  of  low  grade  sugar  or  molasses  with  the  necessary 
water.  It  can  be  used  at  double  this  strength  with  M\  safety  to 
plants.  Applied  as  a  powder,  it  is  best  mixed  with  twenty  parts  of 
wood  ashes,  road  dust,  cheap  flour,  powdered  lime,  or  any  other  cheap 
neutral  powder :  it  can  then  be  placed  in  rough  cloth  bags  and  shaken 
over  the  plants, 


Fig.  96. 
Success  Sprayer  used  on  the  ffround  for 
spray  inff  trees. 


80 


INSECTICIDES    AND    SPRAYING. 


It  is  applicable  against  all  forms  of  biting  insects ;  it  kills  cater- 
pillars, locusts,  leaf-eating  beetles,  and  other  insects  wbich  eat  leaves. 
For  an  average  crop  of  cotton,  young  juari  or  maize,  pulse,  castor,  wheat, 


Fig.  97. 
Success  Kiiajpsacic  MacJiive  :  lelon-'— left,  Bordeavx  nozzle  ;  right,  Vermorel  nozzle, 

etc.,  from  80  to  100  gallons  of  mixture  are  required  per  acre  using 
from  1  to  1^  lbs.  of  lead  arseniate.  This  explains  its  small  poison- 
ous effect  on  cattle,  since  there  is  so  little  arseniate  actually  on  each  plant. 
An  insect  eats  so  large  a  proportion  of  food  compared  to  its  size,  that  it 
absorbs  relatively  much  more  of  the  poison  and  is  killed.  Experiments 
made  in  the  Punjab  with  bullocks  fed  on  fodder  dipped  in  the  mixture 
showed  that  no  harm  resulted,  and  that  freshly-sprayed  fodder^  could 
safely  be  fed  to  cattle.  As  a  matter  of  practice,  the  lead  arseniate 
would  not  remain  on  a  plant  after  the  lapse  of  a  week  or  longer,  and 
the  crop  would  have  scarcely  any  poison  on  it  after  cutting  and  harvest- 
ing.    In   small  gardens,  in  plots  of  vegetable  crops,  it  is  simply  applied 


KEROSENE   EMULSION.  81 

by  means  of  tho  hand  sprayers,  and  it  slionld  1)0  kept  for  this  purpose. 

On  farms,  it  is  useful  a.o'ainst  many  pests  wliicli  attack  valuable  crops 
and  render  useless  the  results  of  other  experiments  whoso  value  is  shown 
by  comparative  yields.  Every  ex]wrimental  farm  shovild  keep  and  use 
lead  arseniate,  applying  it  with  a  good  spraying  machine  and  in  powder 
form.  It  is  obtainable  from  chemists  at  Re.  1  per  lb.  in  powder  or  paste 
form.  The  paste  contains  33  per  cent,  of  water,  and  1|  lbs.  of  paste 
are  sold  as  one  pound  of  lead  arseniate  and  should  be  used  as  one  pound 
in  mixing  with  water  before  spraying. 

Kerosene  Emulsion. 

The  most  useful  and  simple  contact  poison  is  kerosene,  the  ordinary 
refined  kerosene  used  for  burning  in  lamps.  It  kills  all  insects  when 
applied  to  their  bodies,  though  its  action  is  not  fully  understood.  It 
acts  partly  by  mechanically  closing  the  respiratory  openings  on  the  side 
of  the  body,  thereby  asphyxiating  the  insects ;  possibly  it  has  a  directly 
poisonovis  effect  on  the  tissues  of  the  insects  when  the  vapour  is  absorbed 
through  the  system  of  air  tubes  which  penetrate  the  body.  Applied  by 
itself,  kerosene  kills  the  parts  of  the  plants  on  which  it  is  placed  so  that 
the  application  of  undiluted  kerosene  is  as  a  rule  fatal  to  plants.  It 
has  therefore  to  be  applied  in  a  diluted  form,  and,  as  it  does  not  mix  with 
water,  it  is  made  into  an  emulsion  with  soap  and  water.  An  emulsion 
of  kerosene  consists  of  water  with  kerosene  in  very  minute  drops  ;  and  on 
applying  such  an  emulsion,  the  water  evaporates  leaving  a  minute 
quantity  of  kerosene  on  the  plant,  which  is  fatal  to  the  insects,  but  does 
not  injure  the  plant.  The  value  of  kerosene  emulsion  lies  simply  in  the 
fact  that  it  can  be  applied  at  such  strength  as  to  be  fatal  to  many 
insects  and  yet  not  injurious  to  the  tender  tissues  of  the  leaf. 

Kerosene  emulsion  is  prepared  by  boiling  a  solution  of  soap  and 
water,  adding  kerosene  and  agitating  or  beating  up  the  mixture  so  as  to 
break  up  the  oil  into  very  minute  drops,  which  gives  the  liquid  a  creamy 
white  appearance.  Such  an  emulsion  can  be  made  very  strong  and 
afterwards  diluted  with  cold  water  to  the  proper  strength  for  applying  to 
plants.  In  cold  countries,  kerosene  can  be  applied  to  leafless  dormant 
trees  in  much  greater  strength  than  in  hot  climates.  In  India  a 
strength  of  10  per  cent,  of  kerosene  can  rarely  be  exceeded.  Kerosene 
has  a  peculiar  way  of  "  wetting "  or  penetrating  insects  which  are 
protected  by  a  covering  of  mealy  white  wax.  It  is  therefore  particu- 
larly effective  against  mealy  bugs.  It  kills  aphis  (Green-fly),  the  softer 
scale   insects,   green   bugs^   small  sucking  insects  and  also  some  of  the 


82  INSECTICIDES  AND  SPRAYING. 

more  delicate  caterpillars.  Its  use  is  strictly  limited  to  these  insects  and 
it  cannot  be  used,  for  instance,  to  kill  large  caterpillars  which  are  best  dealt 
with  by  means  of  a  stomach  poison. 

Kerosene  emulsion  applied  in  the  ordinary  tin  hand  sprayer,  is  an 
excellent  remedy  for  the  aphid cb  which  attack  cotton,  tuer,  beans,  pulses 
and  other  field  crops.  In  botanic  gardens  it  is  useful  against  all  aphis 
and  the  majority  of  the  scale  insects.  In  vegetable  gardens  it  can  be 
safely  applied  against  similar  pests,  and  is  often  usefully  applied  over 
the  whole  of  a  garden  to  drive  out  unwelcome  intruders  such  as  crickets, 
grasshoppers,  leaf-eating  beetles,  plant  lice,  jumping  lice  and  other 
insects  which  are  apt  to  gather  in  a  well  watered  garden. 

Crude  Oil  Emulsion. 

The  heavier  petroleum  oils  have  a  more  permanent  and  thorough 
insecticidal  effect,  especially  where  the  climate  is  hot  and  the  lighter  oils 
soon  evaporate.  The  ordinary  emulsions  cannot  l)e  made  with  the  crude 
oil,  the  best  emulsions  containing  crude  oil  being  made  by  a  special 
process.  Such  an  emulsion,  containing  80  per  cent,  of  crude  oil,  with  20 
per  cent,  of  whale  oil  soap,  is  prepared  and  sold,  under  the  name  of 
"  Crude  Oil  Emulsion.^'  It  was  made  at  the  Entomologist^s  suggestion, 
and  analysis  shows  it  to  be  pure,  containing  the  ingredients  given  above. 

To  use  the  emulsion,  it  needs  to  be  mixed  with  cold  water  in  the 
proportion  of  \  pint  to  a  kerosene  tin  of  water  (-i  gallons).  This 
amount  measured  and  placed  in  a  bucket  or  tin,  is  readily  mixed  with 
water  by  pumping  water  on  it  from  a  spraying  machine  or  rubbing  up 
the  emulsion  by  hand.  It  makes  a  white  milky  fluid,  remaining  fit  for 
use  for  several  days,  which  needs  no  further  preparation  before  application. 
This  is  the  usual  strength  :  it  may  be  made  twice  as  strong,  and  can  then 
still  be  used  safely  on  all  but  very  delicate  plants. 

Like  kerosene  emulsion,  this  is  simply  a  useful  contact  poison.  It 
is  harmless  to  all  animals  if  eaten  and  has  a  deadly  effect  on  insects  only 
when  they  are  well  wetted  with  it.  It  should  be  applied  in  the  form  of 
fine  mist  by  means  of  a  good  spraying  machine.  For  all  soft  insects 
such  as  aphis  (Green-fly),  mealy  bug,  thrips,  green  bug,  leaf  hoppers, 
small  caterpillars,  etc.,  it  is  effective.  One  application  kills  the  greater 
number  and  a  second  application  completes  the  operation.  In  gardens,  on 
fruit  trees,  on  ornamental  plants,  on  vegetables,  it  is  a  useful  application 
for  these  diseases  and  has  a  further  use  in  driving  off  many  other  insects, 
Avhich,  though  not  killed  by  it,  find  it  objectionable.  It  has  a  certain 
value  also  in  houses,  which  are  infested  with  obnoxious  insects,  etc,     It 


IIOSIN   WASHES.  83 

acts  simply  as  a  lii^'h  class  insocticidal  soap,  witli  a  loss  objectionable 
smell  than  carbolic  preparations.  In  this  way  it  is  deadly  to  fleas  for 
instance. 

It  has  a  further  value  on  domestic  animals  :  kerosene  is  an  excellent 
application  for  the  skin  and  there  is  "no  better  way  of  applying-  it  than 
in  the  form  of  soapy  emulsion.  For  ticks,  fleas,  and  other  insects 
infesting'  cattle,  horses,  dogs,  elephants,  sheep,  etc.,  this  emulsion  should 
be  used,  at  the  same  time  destroying  the  insects  and  improving  the  skin. 

It  is  obtainable  in  five-gallon  drums  from  chemists  at  Rs.  8-14-0  per 
drum. 

Rosin  Washes. 

Rosin  has  for  many  years  formed  the  principal  ingredient  of  many 
excellent  washes  for  sucking  insects.  When  boiled  in  water  with  a 
suitable  chemical,  rosin  dissolves,  forming  a  clear  brown  wash  which  can 
bo  safely  applied  to  plants  at  a  strength  sufficient  to  kill  many  insects. 
It  is  used  in  this  way  against  many  of  the  most  resistant  scale  insects. 
A  rosin  wash  of  this  kind  on  drying  forms  a  varnish,  which  asphyxiates 
some  insects  by  closing  the  stigmata  on  the  sides  of  the  body  through 
which  they  obtain  air.  It  needs  to  be  applied  as  a  fine  mist,  by  means 
of  a  good  spraying  machine,  and  then  has  a  considerable  wetting  power, 
covering  the  insects  with  a  film  of  liquid  which  on  drying  kills  them. 

There  are  a  variety  of  formulae  for  preparing  this  wash.  Two  may 
be  taken  as  being  the  simplest  and  best,  both  having  been  tested  in  India 
and  found  fully  effective.  (See  Appendix  A,  page  284.)  These  washes 
are  similar  in  effect  and  use.  The  second  contains  fish  oil  soap  as  well  as 
rosin  and  is  a  more  powerful  wash  in  consequence.  As  caustic  soda  and 
fish  oil  are  less  easy  to  obtain  than  washing  soda,  the  first  wash  should 
generally  be  used.  Only  when  large  quantities  are  to  be  prepared  is  it 
advisable  to  use  the  second  wash.  The  rosin  used  must  be  the  clear  brown 
fir  tree  rosin  imported  from  Europe.  This  rosin  may  also  be  obtained 
from  the  Forest  Department  at  Dehra  Dun  and  Naini  Tal. 

The  washes  cost  about  Rs.  3  per  100  gallons,  or  Rs.  4  per  100  gallons 
on  estates  far  from  the  coast  and  a  railway  station. 

These  washes  are  for  use  against  scale  insects  such  as  brown  bug, 
green  bug,  black  bug,  etc.,  also  against  green  fly  (aphis)  and  similar 
small  sucking  insects.  They  have  not  the  wetting  power  of  kerosene 
emulsion  and  so  are  less  effective  against  mealy  bug  or  other  mealy 
insects.  They  are  excellent  contact  poisons,  useful  against  a  variety  of 
pests.  Diluted  wash  (1  lb.  of  rosin  to  10  gallons  of  water)  is  also 
•valuable  with  lead  arseniate,  used  as  a  stomach  poison,  since  it  protects  the 


84)  INSECTICIDES   AND   SPRAYING. 

latter  from  rain  and  liolps  it  to  remain  on  tlio  plant.  The  wash  lias  of 
itself  no  poisoning-  effect  on  eattle  or  other  animals,  and  may  be  safely- 
applied  at  all  times.  It  has  also  no  effect  as  a  stomach  poison  against  cater- 
pillars, etc.,  and  is  intended  simply  as  an  efficient  contact  poison  against 
all  small  sncking-  insects  except  the  mealy  ones. 

Tobacco. 

Fermented  tobacco  forms  a  decoction  which  acts  as  a  mild  stomach 
poison  and  also  as  a  contact  poison.  It  requires  to  be  soaked  in  water  to 
extract  the  alkaloids  and  then  is  best  nsed  with  the  addition  of  soap. 
It  is  a  weak  insecticide,  valuable  against  plant  lice,  mealy  bugs,  soft 
sucking  insects  and  very  small  caterpillars,  but  not  so  effective  as  any  of 
the  above  mixtures.  It  is  obtainable  in  many  parts  of  India,  and  the  wash 
is  best  prepared  from  the  stalks  and  refuse  of  the  leaf  tobacco. 

Sanitary  fluid. 

The  liquids  called  by  this  general  name  consist  largely  of  creosote 
oil  containing  carbolic  acid  (phenyl).  Mixed  with  water  they  emulsify, 
owing  to  the  presence  of  rosin  soap,  and  in  weak  emulsion  are  excellent 
contact  poisons.  This  is  an  insecticide  not  in  general  use  elsewhere 
but  which  has  given  excellent  results  in  India.  A  strength  of  one 
in  one  hundred  of  water  is  excellent  against  all  forms  of  soft  sucking 
insects,  against  plant  lice,  mealy  bug,  green  bug,  etc.  At  a  strength  of 
one  in  sixty  of  water,  it  is  a  powerful  insecticide,  which  kills  all  but 
the  most  resistant  sucking  insects  and  has  a  considerable  effect  on  cater- 
pillars, small  grasshoppers,  etc.  At  greater  strength  it  burns  the 
foliage  of  actively  growing  plants  ;  it  was  used  at  one  in  forty  against 
the  Bombay  locust,  killing  a  large  percentage,  and  at  one  in  twenty 
killing  everyone  sprayed,  without  injury  to  the  hardy  foliage  of  forest 
trees. 

Other  contact  poisons. 

Countless  mixtures  have  been  used  as  contact  poisons  since  these 
were  first  tested  and  a  great  variety  are  still  in  use.  In  India  only 
what  are  known  in  Europe  as  "summer  washes"  can  be  used,  which 
restricts  the  available  number.  There  is  sufficient  latitude  in  the  above 
mixtm'es  to  suit  every  case  and  no  good  will  be  done  by  discussing  the 
hundreds  of  mixtures  recommended.  This  applies  also  to  the  patent 
insecticides  ;  none  are  yet  proved  to  be  as  good  as  the  insecticides  made 
on  the  spot  and  none  have  the  combined  efficiency  and  usefulness  of  crude 


INSBCTICIDES.  85 

oil  emulsion.  Any  one  requiring  a  made-up  contact  poison  will  find  this 
suitable  ;  other  made-up  contact  poisons  can  be  purchased  ;  McDougaFs 
insecticide  is  an  example,  which  acts  solely  as  a  contact  poison.  It  is 
valuable  as  a  ready-made  and  effective  contact  poison,  which  acts  with 
much  the  same  effect  at  the  same  strength  as  crude  oil  emulsion,  the 
latter  being  far  cheaper.  Both  have  been  thoroughly  tested  and  both  can 
be  recommended. 

Insecticides  are  not  like  patent  medicines,  requiring  only  to  be  applied 
(or  taken),  when  they  do  the  rest.  They  must  be  used  in  good  time  ; 
an  acre  of  mustard  that  was  badly  infested  with  aphis  required  two  hun- 
dred and  fifty  gallons  of  insecticide  to  kill  every  aphis,  or  three  times  the 
amount  required  to  destroy  the  same  aphis  at  the  beginning  of  the  attack 
on  another  acre.  They  must  also  be  applied  intelligently  and  vigorously, 
with  the  express  object  of  destroying  the  insect  and  not  because  it  is  the 
right  thing  to  do.  They  must  be  applied  properly,  with  an  under- 
standing of  what  they  are  meant  for  and  will  effect. 


Part  III. 


INSECTS    INJURIOUS  TO   CROPS, 


CHAPTER  VIII. 

PESTS  OF  THE  COTTON  PLANT. 

THE  cotton  plant  suffers  from  a  number  of  insect  pests  which  lessen  the 
vigour  of  the  plant  and  diminish  the  actual  yield  of  the  lint  and  seed. 
These  pests  are  widespread  in  India,  do  a  great  aggregate  amount  of 
damage  and  largely  reduce  the  yield  of  probably  every  acre  in  India ;  but 
they  are  disregarded  by  the  cultivator,  who  is  not  aware  that  he  can,  by 
adopting  simple  measures,  obtain  a  larger  yield  of  finer  cotton.  These 
pests  include  the  boll-worms,  of  which  there  are  three  species,  two 
identical  in  almost  all  but  name  and  one  distinct  species ;  the  two  beetles 
that  attack  the  stem ;  two  bugs  that  attack  the  bdlls  ;  and  two  caterpillars, 
an  aphis  and  a  leaf-hopper,  that  attack  the  leaves.  There  are  in  addition 
a  variety  of  minor  pests  which  are  not  exclusively  pests  of  cotton  and 
which  appear  only  casually. 

The  Spotted  BolUworm. 

Caterpillars    which  destroy  ripening  bolls   of   the   cotton  plant  and 

which  may  be  found  by  looking  for  such 
injured  bolls  before  the  cotton  ripens.  They 
are  easy  to  recognise  and  readily  reared  to 
the  imag'o.  The  life  history  is  typical  of 
the  moths. 

The  term  boll-worm  is  in  America  applied 
to  the  caterpillar  described  in  this  book  as  the 
Gram  Caterpillar  (see  page  144) .  In  India 
this  insect  does  not  attack  cotton,  its  place 
being*  taken  by  the  two  spotted  boll-worms 
/*^.*     ■    ,  and  the   pink  boll- worm,  the  latter  being 

Boll  containing  Boll-worm.  t  i  i 

discussed  separately. 

Life  History. — Eggs  are  laid  by  the  moth  singly  on  the  bracts,  bolls 

and  terminal  leaves  of  the   cotton-plant.     Each  o.^^^  is   small,  not  more 

Figures.  "Where  a  fifture  is  saiil  to  be  magnified,  and  a  hair  line  is  found  beside  the 
insect,  this  line  represents  tbe  iictuanengtli  of  the  insect  as  drawn.  When  there  is  no  hair 
line,  the  statement,  for  example  "  magnified  three  times,"  means  that  each  lineal  dimension 
is  three  times  htrger  in  the  figuie,  the  figures  being  thus  actually  nine  times  magnified  if 
we  consider  the  area  it  covers.  A  linear  magnification  of  even  three  is  considerable,  and  in 
comparing  an  insect  with  a  fignre  (in  the  endeavour  to  identify  the  insect  wilh  the  figure) 
a  good  lens  must  be  used;  the  human  eye  cannot  compare  a  small  insect  with  its  enlarged 
figure  unless  the  insect  is  jiresented  to  it  at  least  as  large  as  the  figure,  A  lens  magnifying 
ten  diameters  will  be  sufficient  for  every  insect  figured  in  this  volume,  but  it  is  impossible 
to  compare  insects  and  tlie  figuifs  nnlses  a  lens  is  used.  Where  uo  magnification  is 
mentioned  and  no  liair  line  occurs,  the  figure  is  the  natural  size. 


x^ 

£•' 

I 

90 


PESTS  OF  THE  COTTON  PLANT. 


than  one-fiftieth  of  an  inch  across,  round,  of  a  bluish  colour,  finely  ribbed 
and  marked.  Within  a  few  days  it  hatches  to  a  tiny  dark  coloured 
caterpillar,  which  feeds  first  on  the  bracts  and  flowers  or  eats  straig-ht 
into  the  rind  of  the  boll.     In  the  former  case  it  attacks  the  bolls  within  a 

few  days.  When  no 
bolls  are  formed,  it  tun- 
nels doAvn  the  shoots, 
commencing"  at  the  tip 
and  eating"  for  a  consi- 
derable distance  down 
the  shoot,  thus  des- 
Fio.  99.  troying    it ;     normally 

Spoiled  BoU-worm.     {3Iagmfiedfoin- times.)  it  cuts  its  way  through 

the  rind  of  the  boll  and  the  dcA^eloping"  lint,  until  it  reaches  a  seed, 
which  it  eats.  Having"  destroyed  one  seed  it  eats  another.  If  the  bolls 
are  small,  they  frequently  drop  off,  but  if  a  larg-e  part  of  the  seeds 
are  eaten,  the  lint  is  destroyed  and  the  boll  filled  with  excrement. 
A  single  caterpillar  will  rarely  destroy  more  than  one  large  boll 
but  becomes  full-fed  in  the  first.  More  than  one  is  rarely  found  in 
a  boll  unless  small  ones  enter  a  boll  already  tenanted  by  a  large  one. 

When  the  caterpillar  is  full  fed,  it 
leaves  the  boll  and  prepares  a  cocoon  of 
tough  grey  silk  Avithin  which  it  transforms 
to  the  pupa.  In  the  black  cotton  soil  of 
Western  India,  this  is  found  in  the  cracks 
and  crevices  of  the  soil.  In  Cawnpore, 
Mr.  J.  M.  Hayman  states  that  it  is  found 
"on  the  bolls  or  bracts,  generally  between 
the  two,^'  and  this  is  the  case  also  iu 
Beliar  and  the  Punjab. 

The  period  of  pupation  is  from  8  to  10 
days  but  may  be  longer  in  the  cold  wea- 
ther. Eventually  the  moths  come  out, 
I)air  and  lay  eggs,  each  moth  laying 
about  sixty  eggs.  The  shortest  total  life 
history  occupies  about  one  month.  Moths 
are  to  be  found  flying  in  the  dusk; 
during  the  day  they  hide  in  the  ground 
or  on  the  cotton  plants.  They  are  not 
attracted  by  light.  Both  species  also  feed 
upon    hJiindi     [Hibisms     eaculent'm),     des- 


Fia.  100. 


Spotted  Boll-toorm. 
{3Iagnified  four  times.) 


gpdTfED    BOLL-WOUM. 


91 


Fig.  101. 

Cocoon  of  Spotted  Boll-worm. 
{Magnijied  three  times.) 


troying"  the  fruits  or  the  succulent  stems.     In  Western  India  these  insects 

are  active  tbroug-hout  the  winter,  where 

the  temperature  does  not  fall  so  low  as 

in  Northern  India.     From  Aug-ust    or 

September  to  the  following-  January  or 

February  there  is  abundance  of  cotton  in 

which  they  multiply.     In  places  where 

the  temperature  falls,  as  in  the  Deccan, 

Northern      India      and      Behar,     they 

hibernate  as  pupae,  rarely  as  eggs,  larvae 

or  moths,  until  March.     If  cotton-plants 

are   left    standing   in    the   field    or     if 

bhindi  is  available,  they  then  find 
food;  if  not,  they  remain  dormant 
as  moths  or  possibly  pupuj,  until 
the  rains.  Where  cotton  is  grown 
throughout  the  year,  it  is  conti- 
nually attacked  except  in  the  cold 
weather.  Both  species  are  widely 
distributed  in  India  and  practically 
rang-e  throughout  the  plains. 

Spotted  boll-worms  are  attacked 
by  three  distinct  parasites,  two  ich- 
neumons and  one  tachiuid  fly.  Of  these,  one  ^ 
is  generally  distributed  and  a  very  important 
check  on  the  increase  of  the  insect ;  the  fly  ^ 
has  been  found  in  some  scattered  localities 
and  may  be  an  insect  of  some  importance. 

Description. — The  moth  of  the  com- 
moner species  ^  is  coloured  with  a  broad  green 
band  extending  from  the  base  to  the  apex  of 
each  wing.  This  green  band  may  be  absent, 
the  whole  wings  being-  ochreous  or  buff. 
The  other  species*  has  the  forewings  a 
bright  green.  In  both  species  the  moth 
measures  a  little  under  half  an  inch  in 
length,  the  expanded  wings  nearly  one  inch. 
The  lower  wings  are  white,  and  the  under  ^^^-  103. 

surface  of  the  body  nearly  white.  "^^^^'^^  Boll- worm  Moth. 

''  J  {Magnified  three  times.) 


Fia.  102. 

Spotted  Boll-worm  Moth. 

{^Magnified  twice.) 


>  96.  Mhogas  lefroyi.     Ashm.     (Chalcida?.)     |  »    73.  Tlarias  fabia.     Stoll.     (Noctuidte.) 
2  99.  Flectops  orbata.  VVied.     (Tachiaidse.)  j  *  108,  JEarias  insulana.  Boisd.  (Noctuida;.) 


9^  pjjsTS  OF  ^the  cotton  plant. 

The  caterpillars  are  short  and  thick,  not  more  than  two-thirds  of  an 
inch  long-  when  full  grown.  The  colour  is  very  variable,  a  mixture  of 
white,  g-reen  and  black,  with  orange  spots.  The  predominant  colour  may- 
be a  dull  greenish  white,  with  black  marks  and  small  orange  spots,  or 
black,  with  an  irregular  band  of  greenish  white  from  head  to  tail  with 
orange  spots  on  the  sides.  There  are  tubercles  on  each  segment,  bearing 
hairs ;  the  orange  spots  appear  only  in  fairly  advanced  larvae  and  the 
quite  young  caterpillars  are  darker.  Legs  and  prolegs  are  present,  the 
head  is  dark  in  colour  and  there  is  a  dark  prothoracic  shield. 

The  cocoon  is  less  than  half  an  inch  long,  oval  and  flattened,  made 
of  grey  silk  closely  woven.  It  has  a  resemblance  to  the  grey  woolly  buds 
that  fall  off  the  cotton-plant. 

Bemedies. — The  treatment  of  this  pest  depends  upon  the  conditions 
under  which  cotton  is  g'rown,  and  the  variety  of  cotton.  Certain  varieties 
show  a  complete  or  partial  immunity  to  it,  but  it  is  uncertain  how  far 
any  variety  will  prove  immune  when  grown  as  a  field  crop.  The 
varieties  now  grown  as  field  crops  are  apparently  all  attacked.  There  is 
only  one  direct  remedy  that  can  at  present  be  advised  for  general 
adoption.  It  is  applicable  only  to  cottons  which  produce  a  crop  of  bolls 
at  one  time  and  is  ineffective  in  varieties  which  continue  to  produce 
bolls  over  a  long  period.  It  consists  in  destroying  as  many  of  the 
caterpillars  as  possible  in  the  shoots  of  the  cotton  or  in  the  first  bolls. 
The  first  brood  of  boll-worms  is  found  in  the  shoots  and  in  the  early 
bolls ;  the  dead  shoots  are  readily  seen  and  destroyed,  the  attacked  bolls 
are  easily  found  and  burnt.  There  is  no  loss  of  crop,  as  these  boUs  will 
never  yield  cotton,  and  it  is  very  important  to  check  the  first  brood  which 
soon  becomes  a  very  large  second  brood  if  left  alone.  This  method  can 
be  carried  to  the  degree  of  removing  all  the  early  bolls. 

Another  treatment,  still  in  the  experimental  stage,  consists  in 
spraying  with  lead  arseniate  when  the  bolls  first  form.  A  preventive 
measure  of  some  importance  is  to  remove  the  plants  when  the  crop  is 
picked.  It  is  not  uncommon  to  see  stray  plants  still  living  in  the  hot 
weather  after  the  crop  is  harvested,  which  help  the  pest  to  increase  at  a 
very  critical  time,  especially  if  showers  fall  and  the  cotton  makes  a  littlc 
growth. 

The  importance  of  bhindi  as  an  alternative  food-plant  is  also ^ great. 
"Where  bhindi  is  grown,  the  insects  can  breed  in  it  when  cotton 
is  not  available.  Where  cotton  is  a  staple  crop,  bhindi  should  not  be 
grown  except  when  there  is  cotton.  It  should  not  be  grown  in  Gujarat, 
for  instance,  from  February  to  August,  as  it  helps  the  pest  to  increase 
during  the    hot  weather  and  early  rains,  providing  a  large  number  of 


PINK    ■nOLL-WORM. 


93 


mollis  to  In'ood  oaf ovpi liars  wliicli  attack  tlio  ontton  in  Auq-nst  and 
Scptomber.  Expovlraonts  avo  in  pvno'ress  to  usn  bhindi  as  a  trap  crop  in 
or  aronnd  cotton,  in  tlio  liopo  of  colU^cting'  tlio  insects  in  that  crop  wliicli 
can  then  bo  destroyed.  The  success  obtained  during'  the  past  season 
justifies  the  more  extended  trial  of  this  measure. 


The  Pink  Boll=worm. 

Associated  with  the  spotted  boll-worms  is  a  slender  reddish  caterpillar 

found  feedino"  in  the 
green  or  ripe  bolls. 
It  is  easily  distin- 
g'uished  from  the 
other  caterpillars 

found  on  cotton. 

The  moth  lays  a 
number  of  small  flat- 
tened eg-gs,  similar  to 
those  laid  by  the 
majority  of  small 
moths ;  the  eg-gs  are 
deposited  sing-ly  on 
leaves,  stalks  and 
bolls,  and  hatch  in  a 
few  days. 

The  young-  cater- 
pillar is  white,  with 
a  dark  head,  and  is 
found  feeding  on  the  leaves  or  on  the  outside  of  the  boll.  It  does  not 
immediately  attack  the  boll  but  bores  in  through  the  rind  when  it  has  fed 
for  a  few  days  outside. 

Like  the  spotted  boll-worms  this  one  feeds  upon  the  oily  seeds,  eating 
seed  after  seed  until  it  has  become  full  grown.  As  a  rule  one  will  be 
found  in  a  boll  but  exceptionally  several  attack  the  same  boll.  The  full 
grown  larva  is  of  a  white  colour,  with  bright  pink  spots,  more  slender 
than  the  spotted  boll-worms  and  without  processes.  The  larval  life  varies 
in  duration  according  to  the  season  but  occupies  two  to  three  weeks  in  the 
active  period.  The  full  grown  larva  forms  a  slight  cocoon  of  silk,  in  the 
boll  or  on  the  bracts  or  leaves  of  the  cotton.  In  unirrigated  black  cotton 
soil  this  may  be  found  in  a  crack  of  the  dry  soil.     The  shortest  period  for 

'74.     Gelechia  goss  ypiella.     Sauod.     (Tipeidse.) 


Fig.  104. 
Phih  BoU-ivorm.     (Magnified.') 


94 


PESTS    OP   THE    COTTON    PLANT. 


Fig.  105. 

Finl~  Boll-ioorm  Caferpillar  and  Cocoon,  tJieJormer 

magnified,  the  latter  natural  size. 


the   pupa  is   from   fourteen   to   eighteen   days,   after  which    the   moth 

emerges. 

The  moth  is  less  than  half  an  inch  in  length,  the  antennre  filiform,  the 

palpi    upturned,  the  gen- 
eral    colour    grey    brown 

with    dark    blotches    and 

suifusions,      the        wings 

with  long  brown  fringes. 

The    moth    cannot    easily 

be       distinguished     from 

other    Tineid    moths    by 

its       appearance       alone. 

Moths    fly   at  night    and 

dusk :   they  are    attracted 

by    light  and  are   readily 

captured  in  lamp  traps. 
The    pink    boll-worms 

are  most  abundant    when 

the     cotton     forms     bolls 

in  October  or  earlier ;  the  active  period  is  dm-ing  the  rains  and  after ; 

in  many  parts  of  India  the 
larvae  hibernate  in  the  cold 
weather,  but  this  is  not  the  case 
for  instance  in  South  Gujarat. 
In  Behar  the  larvae  live  through 
the  cold  weather  in  the  lint  or 
seed  of  the  cotton,  emerging  as 
moths  only  in  March  or  April ; 
their  further  activity  depends 
upon  circumstances,  the  moths 
laying  eggs  then  if  cotton  is 
available.  There  may  be  a 
further  period  of  rest  during 
the  dry  hot  months  before 
the  rains.  Actually  larvae  have 
been  found  active  in  all  raonths 
of  the  year,  but  there  are  two 
main  periods  of  rest,  from 
November  to  March  and  from 
April  to  June,  depending  upon 
climatic  conditions  and  the  supply  of  food. 


Fig.  106, 

Pink  BoU-irorm  Moth.     {^Magnified  six 

times.) 


PINK    BOLL-WORM. 


95 


The  pest  is  apparently  universal  in  India,  Ceylon,  Burma  and  the 
Straits  Settlements,  causino*  a  very  laro-e  ag-o-re^-ate  loss  to  cotton  in  India, 
which  may  amount  to  at  least  one  crore  of  rupees  annually.  The  destruc- 
tion o£  the  seed,  the 
staining-  of  the 
and  the  loss 
young  bolls  are 
jirincipal  forms 
damag-e.  So  far 
is  known  all  varieties 
of  cotton  now  gn-own 
as  field  crops  in 
India  are  attacked, 
the  American  and 
Egyptian  as  well  as 
the  indigenous.  It 
remains  to  be  seen 
whether  there  are  any 
varieties  of  cotton  im- 


FiG.  107. 

Tarasite  on  Caterpillar  of  Pink  BoU-morm. 
[Magnified  six  times.) 


mune  to  the  pests,  but  none  have  definitely  proved  so  up  to  the  present. 

Unlike  the  other  boll-worms,  this  species  has  not  been  found  attacking 
plants  allied  to  cotton ;  its  wild  food-plants  appear  to  be  trees  with  oily 
seeds  which  are  widely  distributed  in  India. 

Remedies. — The  first  and  most  important  remedy  is  to  check  the 
increase  of  the  pink  boll- worm  by  plucking  off  the  first  crop  of  bolls  if 
they  are  attacked.  When  the  first  bolls  are  forming,  the  first  batch  of 
moths  lays  eggs  on  them  and  the  boll-worm  commences.  If  left  alone 
these  boll- worms  will  emerge  as  moths  and  each  lay  many  eggs.  The 
increase  from  one  pair  of  moths  being  large,  the  second  brood  is  generally 
a  fairly  numerous  one.  Had  this  first  brood  been  destroyed,  it  could  not 
have  multiplied  and  destroyed  so  much  cotton  later  in  the  season. 

The  second  precaution  is  the  treatment  of  seed  by  fumigation  or 
other  means  to  destroy  the  hibernating  larvae.  Fumigation  with  carbon 
bisulphide  after  the  seed  has  been  picked  over  in  the  sun  is  the  most 
effective  method  of  freeing  cotton  from  boll-worms.  Equally  it  is  import- 
ant to  pick  off  the  bolls  which  are  destroyed  on  the  plant.  Leaving  on 
the  plants  the  bolls  that  are  eaten  or  destroyed  assists  cotton  pests  to 
multiply  and  increase.  It  particularly  assists  pink  boll-worms  and  the 
cotton  bugs.  Other  methods  of  treatment,  such  as  the  spraying  of  bolls 
with  lead  arseniate  and  the  use  of  light  traps,  are  as  yet  only  in  the  experi- 
mental stage. 


96 


PESTS  OF  THE  COTTON  PLANT. 


Generally  the  picking  of  the  first  bolls  is  praetieuUy  the  only  method 
that  can  at  present  be  advised.  When  the  cotton  bolls  are  formed  at  one 
season  only  and  the  crop  ripens  (piickly  and  iiearly  simnltaneonsly, 
this  method  is  capable  of  g-eneral  application ;  in  the  case  of  cottons  that 
yield  slowly  and  continuonsly  over  lono^  periods,  it  is  doubtful  if  a  full 
crop  can  ever  be  obtained  or  even  a  reasonable  proportion  of  the  crop. 

For  such  cottons  the  pest  may  be  regarded  as  a  very  serious  one. 
Trap  crops  of  annual  cottons  may  effect  something"  in  the  case  of  valuable 
tree  cottons,  if  such  trap  crops  are  nsed  intelligently,  but  this  method 
also  is  only  in  the  experimental  stage. 

The  Cotton  Leaf=RolIer.i 

A  slender  caterpillar  of  a  pale  greenish  colour  with  a  dark-coloured 
head,  which  lives  upon  the  lower  side  of  the  leaf  of  the  cotton  and  bhindi 
plants,  folding  the  leaf  over  and  eating  it ;  it  is  easily  recognised  and  is  a 
very  common  pest  of  these  plants.  As  a  cotton  pest  it  is  of  some  import- 
ance, especially  in  the  early  life  of  the  plant,  and  needs  to  be  vigorously 
checked  from  the  outset  if  it  is  not  seriously  to  injure  or  delay  the  crop. 

Life  Histori/. — The  female  moth,  flying  in  the  dusk  or  at  night,  lays 
her  eggs  on  the  lower  side  of  the  leaves,  one  here,  one  there  ;  sometimes 
one  on  each  leaf,  often  two  or  more.  The  eggs  are  small,  round  greenish 
objects,  about  the  same  size  as  the  head  of  a  small  pin.  They  hatch  in  a 
few  days  and  a  tiny  slender  caterpillar  comes  out.     The  young  caterpillar 

feeds  upon 
the  leaf  gnaw- 
ing the  lower 
side  ;  it  spins 
threads  over 
and  around  it- 
self as  a  protec- 
tion and  soon 
sheds  its  first 
skin  and  grows 
larger.  It  then 
continues  feed- 
ing upon  the 
leaf  ',  as  a  rule 
it  turns  the 
edge  of  the  leaf 
over  in  a  fold 


*^^ 


S 


Fig.  108. 

Cotton   leaves,   rolled   hy   the   Cotton   Leaf -Holler, 

(The  left  hand  leaf  contains  tioo  caterpillars.) 


37.  Sylepta  dero^ata,    Fabr.     (Pyralidse.) 


ddTTdN    LEAF-ROLLER. 


9^ 


and  binds  it  down  with  silken  threads^  living*  safely  within  this 
fold.  As  it  grows  larg-er,  it  binds  more  and  more  folds  together,  forming' 
a  kind  of  nest  of  rolled  leaf  in  wliich  it  feeds.  In  those  varieties 
of  cotton  Avith  a  large  leaf,  the  whole  or  a  great  part  of  the  leaf  is 
thus  tied  together  and  if  the  caterpillar  eats  much  at  the  base,  the  leaf 
withers.  In  the  case  of  bhindi  or  of  varieties  of  cotton  with  smaller, 
divided  leaves,  the  leaf  may  be  simply  eaten,  not  folded  together  into  a 
compact  bunch.  Especially  is  this  the  ease  in  the  smaller-leaved  cottons, 
Avhere  the  caterpillar  lives  in  the  top  leaves  of  each  shoot  and  binds  them 
all  together.  These  folded  leaves  are  fairly  characteristic  of  this  insect  and 
if  opened  will  be  found  to  contain  one  or  several  caterpillars,  with 
a  mass  of  black  excrement  in  grains.  [Another  caterpillar  (the 
bud  caterpillar  No.  80) 
lives  only  in  the  top  leaves 
of  the  shoot,  binding 
them  into  a  very  compact 
mass,  which  withers  and 
turns  dark ;  one  can  readily 
distinguish  this  by  the 
appearance  of  the  cater- 
pillar, of  which  only  one 
lives  in  each  mass ;  it  is 
small,  not  more  than  half 
an  inch  long,  of  a  distinct 
opaque  dull  green  colour, 
not  shiny  and  transparent 
as  is  this  leaf-roller  (see 
page  99)]. 

The  leaf-roller  grows  to  a  length  of  over  one  inch;  it  is  slender, 
the  body  transparent  with  a  faint  greenish  tinge,  and  the  dark  contents 
of  the  alimentary  canal  showing  through  the  skin  3  the  legs  are  dark, 
and  easily  seen,  the  sucker-feet  long  and  slender.  The  head  and  neck  are 
dark  brown  and  there  are  a  few  long  slender  hairs  on  each  segment. 

After  two  to  three  weeks'"  life  as  a  caterpillar,  the  last  skin  is  shed 
and  the  chrysalis  is  formed.  This  is  shiny  chestnut  brown,  with  no  legs 
or  means  of  locomotion,  about  half  an  inch  in  length.  It  lies  among  the 
twisted  leaves  suspended  by  the  threads  made  by  the  caterpillar,  and  is 
easily  found  by  untwisting  the  rolled-up  leaves.  It  Hes  motionless  for 
eight  days  and  then  opens,  the  moth  emerging. 

The  moth  is  of  a  whitish  colour,  with  a  faint  yellow  tinge,  the  wings 
with  many  fine  dark  lines,  forming  an  irregular  pattern.     It  is  less  than 


Fig.  109. 
3Ioth  of  Cotton  Leaf-Roller.    {Magnified.) 


08  I'kSTS    Oi'    TriE    COTTON    PLANt'. 

one  inch  in  length,  measuring"  one  and  a  hali:  inches  across  when  the 
wings  are  open.  It  is  very  easy  to  rear  and  recognise ;  the  brown 
ehrysahs,  if  left  in  a  box,  will  yield  the  moth  in  a  few  days  and  the  moth 
cannot  easily  be  mistaken  for  any  other  moth  that  lives  upon  cotton. 
The  moths  fly  about  the  fields  in  the  dusk,  lying  hidden  among  the  leaves 
during  the  day.     After  coupling,  the  female  lays  eggs  and  the  moths  die. 

The  whole  life  of  this  insect  occupies  from  three  to  four  weeks,  so 
that  one  brood  succeeds  another  rapidly  during  the  warm  weather.  There 
are  three  broods  at  least  in  cotton  before  the  cold  weather,  and  as  each 
moth  lays  many  egg's,  the  pest  increases  rapidly.  With  the  advent  of 
the  cold  Aveather,  the  pest  disappears.  It  is  not  known  to  be  active 
during  the  winter  months  either  in  Gujarat  or  in  Behar.  It  hibernates 
during  the  cold  weather,  reappearing  with  the  rains  or  rarely  before.  It 
is  not,  therefore,  found  after  November  and  is  a  pest  to  cotton  only  up  to 
this  month. 

The  food-plants  include  both  cotton,  holly  hock  and  "  lady-finger,'^ 
01'  bhindi  {Hibiscus  escidentus).  Possibly  there  are  other  wild  plants  on 
Avliich  it  can  feed.  As  the  latter  plant  is  grown  during  the  rains  as 
a  vegetable,  the  moths  that  come  out  in  the  early  weeks  of  the  rains  can 
lay  eg^B  on  it  and  so  there  may  be  one  or  two  broods  before  it  attacks 
the  cotton.  It  also  breeds  during  the  hot  weather  if  plants  are  available. 
To  both  plants  it  is  destructive  simply  from  the  damage  caused  to  the 
leaves.  Where  it  is  abundant  and  strips  the  plants,  it  may  prove  a  serious 
pestj  the  full  yield  of  cotton  not  being  obtained.  One  of  the  common 
parasites^  a  tiny  black  fly,  lays  its  eggs  in  the  caterpillars ;  the  eggs  hatch 
to  gl'ubs  which  feed  on  the  caterpillar  and  finally  come  out,  to  form  a 
small  egg-shaped  white  cocoon  on  the  plants ;  the  caterpillar  dies  and  this 
insect  does  much  to  check  the  increase  of  the  caterpillar. 

Remedies. — The  pest  is  not  a  very  easy  one  to  destroy  on  cotton,  and 
the  first  consideration  must  be  to  prevent  its  occurrence  as  far  as  possible. 
As  the  pest  comes  from  bhindi,  the  best  thing  is  to  grow  no  bhindi  at 
till  within  reach  of  the  cotton  or  to  grow  it  in  the  young  cotton  plants  and 
tise  it  as  a  trap.  The  indiscriminate  growing  of  bhindi  where  cotton 
is  also  grown  is  the  surest  way  of  helping  the  pest  to  attack  the  cotton. 
Bhindi  should  either  not  be  grown  at  all  until  November,  so  that  the 
pest  may  have  no  food-plant  on  which  to  increase,  or  should  be  grown 
carefully  as  a  trap  crop  for  the  pest.  In  the  latter  ease,  if  it  is  sown 
between  the  cotton,  it  will  come  up  more  quickly  and  the  caterpillars 
win  be  found  first  upon  it.  The  caterpillars  must  then  be  destroyed 
and  the  bhindi  plants  too,  as  sOoli  as  the  cotton  is  large  enough  to  attract 
the  moths  to  lay  eggs*     Two  months  or  ten   weeks  would  probably  be 


COTTON    BUD    CATERPlLLAl?. 


^9 


tlie  time  during  which  the  bliindi  should  be  allowed  io  grow,  after  which 
it  should  be  removed  and  destroyed  with  all  the  caterpillars  and  chrysalides 
on  it.  Some  will  attack  the  cotton  and  then  can  be  removed  by  plucking* 
all  attacked  leaves  and  burning  them.  This  simple  method  should  be 
applied  when  the  bliindi  is  removed,  if  the  latter  is  used  as  a  trap,  or  as 
soon  as  the  pest  is  seen  on  the  cotton.  It  serves  to  destroy  the  first  brood 
on  the  cotton  and  so  to  check  the  pest  from  the  beginmng". 

In  bad  cases  of  attack  on  cotton,  spraying  with  lead  arseniate  is  the 
radical  remedy,  and  where  some  varieties  are  grown  experimentally,  this 
should  be  done.  Where  cotton  is  grown  on  a  large  scale,  the  pest  does 
little  harm  as  it  has  so  wide  a  range  and  does  not  gather  on  particular  plants. 
But  where  cotton  is  grown  on  a  small  scale,  there  may  be  so  much  of  the 
pest  as  materially  to  lessen  the  vigour  of  the  plants,  and  in  this  case  spray- 
ing with  lead  arseniate  is  necessary.  As  a  rule,  the  simple  remedy  of 
picking  off  the  affected  leaves  as  soon  as  they  are  seen  is  the  only  remedy 
necessary.     If  done  in  time,  it  is  entirely  effective  early  in  the  season » 

The  moth  has  a  very  wide  distribution  over  the  East,  from  West 
Africa  to  Siberia  and  Australia.  It  is  not  recorded  as  a  pest  outside 
India,  except  from  East  Africa  and  doubtfully  from  the  Straits  Settle- 
ments. 

The  Cotton  Bud  Caterpillar.i 

A  small  caterpillar  which  lives  on  the  top  of  the  shoot  of  the  cottoll 
plant,  binding  the  leaves  together  into  a  small  compact  knot  which  turns 


Fig.  ho. 

Cot/on  Bud\Caler];jiUar.     [MafjHified four  Hii.es.) 


i*^v,. 


FXG.  111. 
Cotton  Bud  Caterpillar.     {Mayr.ifed fovr  tin.es) 


*  80.  Fhvcita  infusella.    Meyr.     (Pyralldge.j 


II  a 


loo 


PESTS    OF   THE   COTTON    PliANT. 


Fig.  112. 

Cocoon  of  Cotton 

Bud  Caterpillar, 

ti-ith  adhering 

soil. 


browu.     This  jJest  is  easy  to  recognise  from  the  twisted  leaves  at  the  end 

of  the  shoot  and  their  withered  appearance. 

The  caterpillar  is  a  small  opaque  g-reeu  one,  with  faint  longitudinal 
lines  of  browu  pigment  visible  only  when  examined  with 
a  lens.  It  feeds  upon  the  cotton  bud  and  on  the  leaves 
at  the  tip  of  the  shoot,  webbing  these  together  with 
threads.  The  small  brown  pupa  is  fouud  within  the 
twisted  leaves.  The  moth  is  less  than  half  an  inch  long, 
the  antennse  swollen  beyond  the  basal  joint,  the  palpi 
upturned;  the  thorax  and  basal  half  of  the  wings  are 
grey,  the  apical  half  being  darker.  It  flies  in  the  dusk 
and  is  not  readily  noticed.  The  caterpillar  is  found  on 
the  cotton  from  August  to  November,  after  which  it 
hibernates.     When  abundant,  the  plant  grows  short  and 

bushy,  and  in  many  cases  the  insect  does   good  by    effecting    an  even 

pruning.     It  is  a  pest  only  when  abnormally  abundant. 

Indigenous  cottons  similar  to  the  Broach-Deshi,  Goghari,  etc.,  are 

attacked ;  American  and  tree  cottons  appear 

to    be    immune.     The    pest    is    apparently 

widely  spread  in  India  but  nowhere  seriously 

destructive.     It  is  very   easily  checked  by 

pulling  off   the  little  dried  knots  of  leaves 

and     bm'uing    them    with    the    larva     or 

pupa   inside.      Spraying  with  lead   arseni- 

ate    also    checks  it   but    is    not    generally 

necessary.     The  pest  is  one  that  is  on  the 

whole    of    little   importance,  and  generally 

needs    to     be     checked     only    on     experi- 
mental farms  where  the  cotton    plants  are 

required  to    come     to     their   full     normal 

vigour.      Parasites    keep    it    in    check    to 

some      extent.      Where     the   mealy     bug- 
attacks    cotton,    the    two    pests  are    found 


Fig.  113. 


together,    and    often    the     bud    caterpillar 


Moth  of  Cotton  Bud  Caterpillar. 
{3IaffniJied  Jive  times.) 


is  confused  with  the  caterpillar  which  feeds  upon  the  mealy  bui 


The  Cotton  Stem  Borer.^ 

During  the  growth  of  liilton   plnnis,  from  tlio  iinic  the  firs<   flower 
buds  are  formed  until  the   bolls  are  picked,  single  plants  are  found  to 

^  60.  Sphenoptcra  gossypii.    Kerr.     (Buprestidse.) 


COTTOX    RTEAr    nO"RET?. 


witlior,  turn  yellow  and  dio,  apparently 
without  cause.  If  such  plants  are  pulled 
up  and  broken  across  at  the  crown,  it 
will  be  found  that  the  centre  has  been 
eateu  out,  a  round  tunnel  extending-  up 
and  down  the  thickest  part  of  the  stem. 
Possibly  the  insect  causing*  this  damage 
will  be  found  inside  the  tunnel,  and  there 
can  then  be  no  doubt  as  to  the  iden- 
tity of  the  insect.  No  other  insect 
is  known  to  attack  cotton  in  this  way  in 
India,  and  if  such  bored  cotton  stems  are 
found  without  the  insect,  search  for  other 
withered  or  dying  plants  will  probably 
reveal  a  plant  with  this  insect  at  work. 

Life  History. — The  grub  enters  the 
stem  near  the  crown,  hatching  from  an 
egg  laid  there  by  the  beetle.  It  bores 
into  the  stem,  feeding  upon  the  tissues  as 
it  goes,  and  making  a  neat  round  tunnel 
up  and  down  the  centre  of  the  stem.  One 
grub  inhabits  a  cotton  plant  and  its  tunnel 
sooner  or  later  destroys  so  much  tissue 
that  the  plant  dies.  The  grub  is  white, 
in  length  up  to  one  inch,  with  a  slender 
body,  very  much  swollen  into  a  round, 
slightly  flattened  bulb  at  the  front  end. 
The  head  is  small,  in  front  of  the  swollen 
thorax,  and  has  powerful  jaws  with  which 
it  gnaws  away  the  wood.  Legs  are  absent 
and  the  bulbous  swelling  fits  the  burrow  in 
such  a  way  that  the  larva  can  move  by  mus- 
cular contractions  and  expansions  of  this  part. 

When  full  grown  the  grub  eats  a  hole 
almost  to  the  outside,  leaving  the  bark 
intact,  and  turns  to  a  chrysalis  within  the 
burrow.  The  chrysalis  is  white,  becoming 
dark  before  it  emerges,  and  the  legs,  wings 
and  antennae  of  the  future  beetle  may  be 
seen  folded  against  the  body.  It  lies 
naotionless    within   the  burrow    whilst   the 


Fig.  114. 

Stent  Borer  in  Cotton 

Stem, 


10:; 


PESTS    OP    THK    COTTON    PI,\\T. 


beetle  is  gTiulually  fonned.  Tlie  lieeilo  iliai  oraevg-es  is  of  a  dark 
bronze  colour,  hard;  with  leg-s,  wiug's  and  antennae.  It  measures  one-third 
of  an  inch  in  length  and  is  rocog-nisable  by  its  colour,   its   size   and 


appcaraucr    ni 


its    truncated 
front. 

It  enicrg'es  through  the 
thin  bark  left  by  the  grub. 
Having-  mated,  the  female 
beetle  lays  cg-g's  and  dies. 

These  beetles  are  not 
easily  noticed  in  thej  cotton 
fields.  They  fly  actively 
and  are  sometimes  found  on 
four    irregular 


Fig.  115. 
Sfeiii  Borer  Larva. 


as   many   as 


the  leaves  of  the  plant.  There  may  be 
broods  during  the  cotton  season;  the 
"first  is  a  small  one  and  only  few  plants  are  destroyed ;  the  second  is  a 
large  one,  the  beetles  of  tlie  first  brood  laying  many  eggs  ;  the  third 
brood  is  large  but  is  liable  to  suffer  much  from  parasites ;  the  fourth 
brood  may  be  very  small  and  is  not  important,  the  cotton  having  been 


Fig.  116. 
Fupa  in  stem. 


Fig.  117. 

Stem  Borer  Ftqia. 

{Magnified  three  times.) 


Fig.  118. 
Hole  where  Beetle  emerges. 


picked  before  its  arrival.  These  broods  are  quite  irregular  and  not  well 
marked,  since  the  beetles  do  not  all  come  out  at  once.  The  destruction 
to  the  plants  will  be  noticed  when  flowers  come  out ;  it  may  be  seen 
earlier,  depending  upon  the  growth  of  the  cotton. 


rOTTON    STFAl    WEF.VFT., 


]0« 


Tiemeilieft. — Tlio  post  is  easily  eliockod  if  .ill  tlie  withered  plants  avo 
removed  regularly  and  systematically.  It  is  easy  to  see  withered  plants, 
which  can  be  collected  and  destroyed  before  the  beetle  et-capes  from 
them.  There  is  no  other  simple  remedy.  It 
may  be  found  possible  to  apply  a  dressing-  to 
the  plants  that  will  keep  off  the  beetles  and 
prevent  eg-g'-laying-,  but  the  remedy  above  given 
is  so  simple  and  tliorough,  if  carried  out  from  the 
first,  that  there  is  no  reason  to  spend  money  in 
preventing  the  first  brood  from  coming.  It  is 
better  to  let  it  destroy  a  small  number  of  plants 
and  then  make  sure  of  catching  it  in  these 
plants.  Two  parasites  lay  their  eggs  in  the 
grubs  of  this  beetle  in  the  cotton  stem,  whicli 
check  it  to  a  slight  extent.  It  is  better  not  to 
destroy  these  parasites  if  they  are  present  in  the 
cotton  stems,  and  this  may  be  effected  thus. 
Place  all  the  stems  which  are  collected  in  a  box 
or  barrel  with  the  lid  covered  with  thin  cloth,  securely  tied  down.  The 
beetles  and  parasites  will  hatch,  the  latter  being  flies  easily  distinguished 
from  the  bronze  beetles.  The  box  can  be  examined  periodically  and  the 
parasites,  if  any  hatch,  allowed  to  escape.  The  beetles  on  hatching  will 
lie  motionless  in  the  box  and  will  not  attempt  to  escape  if  the  cloth  is 
quickly  lifted,  whilst  the  parasites  are  active  creatures  which  will  fly 
out  of  the  box  at  the  first  opportunity.  The  parasites  wiU  then  go 
to  the  cotton  fields  and  seek  for  grubs  of  the  beetle  in  which  to  lay 
their  eggs. 

This  insect  is  common  in  Gujarat,  the  Deccan,  the  Central 
Provinces,  and  parts  of  the  Punjab.  It  is  rare  in  Behar  and  is  apparently 
not  so  universal  a  pest  as  the  other  insects  that  attack  cotton.  There 
is  no  record  of  its  occurrence  outside  India. 


Fig.  119. 

Stem  Borer  Beetle. 

{Magnijied  jive  times.) 


Cotton  Stem  WeevH.^ 

A  small  white  grub  found  tunneling  in  the  stem  or  branches  of 
certain  races  of  cotton ;  the  grub  is  small,  less  than  one  quarter  of  an  inch 
long,  distinct  in  appearance  from  the  stem  borer. 

This  pest  has  been  found  only  in  Behar  and  has  not  been  under 
observation  for  any  length  of  time.  The  small  white  grub  feeds  on  the 
tissue  of  the  cotton  stem,  making  twisted  galleries  which  it  fills   with 

^142.  (Curculionidse.) 


104 


PESTS    OT"  THE   COTTON    PLANT. 


Fig.  120. 
TJie  Cotton  Stem  Weevil. 
(Afagnified  seven  times.) 


excrement.     Tlie  grub  is   white,  leg-less,  not   conspicuously   swollen   in 

front.  It  transforms  in  the  burrow  to  a  small  white  pupa  without  cover- 
ing. From  this  a  small  weevil  emerges, 
in  length  about  one-eighth  of  an  inch, 
of  a  brown  colour  with  black  and  whitish 
marks.  The  insect  has  a  slender  curved 
beak. 

The  weevil  is  so  small  and  its 
flight  so  quick  and  active  that  it  is 
not  easy  to  find  in  the  field.  They 
may  be  found  coupling  on  the  cotton 
plants  prior  to  egg-laying,  but  are  not 
likely   to   be  seen  or  recognised.     As  a 

result  of   the  attack  of  this  pest,  the   cotton  branch   dies  or   the  stem 

of  the    cotton  plant    swells   and   in  a  high    wind  breaks.     The  peculiar 

swelling  of  the  base  of  the  stem  of  the  Broach- 

Deshi  cotton  plant  is  a  symptom  of  this  pest,  and 

though  the  plant  lives,  it    may  be  destroyed   in 

the    first    high    wind.     In    Behar,    the    Broach, 

Goghari  and  other  Bombay-Deshi  cottons  were 

attacked   in   the    stems,    the    Egyptian    cottons 

seriously  injured   in   the    same  way  and  certain 

varieties  of  tree  cotton   {Caravonica  and  others) 

attacked  in  the  branches.    Other  tree  cottons  and 

many   indigenous    cottons    were    on   the     whole 

exempt  from  attack.     Once  infested  the  plant  is 

doomed  and  only  preventive  measures  are  effective. 

Experiments   with   trap  cottons   and   other  trap 

plants  are  in  progress,  and  further  investigation 

may  reveal  some  method  of  checking  it.    The  pest  is  unlikely  to  occur  only 

in  Behar  and  may  be  looked  for  in  other  parts  of  India. 


Fig.  121. 

T7ie  Cotton  Stem  Weecil. 
{3Iagnified  seven  times.) 


The  Red  Cotton  Bug.i 

This  insect  is  the  most  familiar  insect  pest  of  cotton  occurring  gen- 
erally in  India,  attracting  attention  rather  from  its  vivid  colouring  than 
its  destructiveness.  It  is  almost  identical  with  the  Red  Cotton  Stainer 
of  the  United  States  and  West  Indies.  The  full  grown  insect  measures 
a  little  more  than  half-an-inch  from  the  head  to  the  tip  of  the  wings. 
Red  is  the  predominant  colour,  the  eyes,  the  antennae,  a  spot    on   the 

'  69,  D^sdercus  cingulatusf.     Fabr,  (Pyrrhocoridse.) 


HED   COTTON   BUG. 


105 


scutellum  and  on  eaoli  wing-  beino-  black,  iho  apex  of  the  wings  absobitely 
black  and  forming  when  folded  a  black  diamond  on  the  upper  surface. 


Fig.  122. 

Bug  mist  alien  for 
Hed  Cotton  Buff. 
{From  Distant.) 


Fig.  123. 
Eed  Cotton  Biuf. 

{Magnified.') 
{From  Distant.) 


Fig.  124. 

Bug  mislaJcen  for 
Bed  Cotton  Bug. 
(From  Distant.) 


There  are  white  transverse  lines  on  the  lower  surface  of  the  body  and  a 
tiny  white  ring  behind  the  head  ;  the  long"  sucking'  beak  lies  between  the 
legs.  The  insect  is  not  likely  to  be  confused  if  carefully  examined,  but 
there  are  other  bug's  which  have  a  g-enerally  similar  appearance,  though 
(hstinct  markings. 

Iii/e  Uistori/, — The  eg'gs  are  laid  in  a  loose  mass  under  the  surface 
of  the  soil,  usually  in  a  crack  or  depression,  which  the  female  covers  with 
earth  after  depositing  the  eggs.  Each  e^^  is  round,  of  a  light  yellow 
colour ;  between  fifty  and  sixty  are  laid  by  each  female.  In  less  than 
a  week  the  eggs  hatch  to  small  active  red  insects ;  wings  are  not 
present,  the  upper  surface  of  the  abdomen  being  red,  with  a  central  row 
of  black  spots  and  a  row  of  white  ones  on  each  side.  In  other  respects 
the  young  insect  is  similar  to  the  full  grown  winged  insect. 

The  young  moult  periodically  and  grow  larger.  After  the  third 
moult  the  wings  commence  to  appear  as  small  back  lobes  on  the  base  of 
the  abdomen.  These  grow  larger  at  each  moult ;  there  are,  as  a  rule,  five 
moults  in  all,  the  insect  appearing  with  perfect  wings  after  the  fifth. 

The  male  is  slightly  smaller  than  the  female  ;  these  couple  and  the 
females  may  then  be  recognised  by  the  swollen  abdomen. 

The  red  cotton  bug  also  attacks  the  bhindi  plant  {Hibiscus  esculen- 
tus)  and  the  silk  cotton  tree ;  enormous  numbers  are  found  when  the 
latter  is  fruiting  in  April  and  it  breeds  extensively  at  this  time.  On 
cotton  it  feeds  on  the  leaves  or  stems,  but  especially  on  the  seeds  in  the 
green  or  ripe  boll.  It  may  be  found  clustered  on  the  bolls,  the  beak 
firmly  fixed,  sucking  out  the  juice,     Where  either  cotton  or  bhijidi  are 


]06 


PESTR    OF    THE    COTTOX    PLANT. 


-1^ 

I  '  . 

■'  ^^ 

w^\, 

^^^i^ 

^^  ^*^^^ 

! 

Fm.  125. 
Jied  Cotton  Buij. 


plentiful,  tho  insect  becomes  very  abnndant,  increasing  rapidly  in  warm 

■\veatlier.     This  insect  has 

also     been      reported     as 

attacking-    the    flowers    of 

Hibiscus  at  the    Saharan- 

pore     Botanical     Gardens. 

There      arc      no     definite 

broods,  insects  of  all  ag-es 

being-       found       tog-ether. 

Reproduction     ceases      if 

food      is     not     abundant, 

the   mature   insects    alone 

being    found.     This    may 

also     occur    in    the    cold 

weather,     though      it     is 

not    invariable,      and     in 

Western  India    all  stages 

may    be    found     in     the 

cold  weather.  ^'''^ 

If  the  insect  becomes  abundant,  it  weakens  the  plant  and  also 
destroys  the  seeds.  This  is  the  principal  damage  it  causes  to  cotton,  one 
that  is  not  attributed  to  the  right  cause  in  most  cases,  as  there  may  be 
nothing  to  show  what  injured  the  seeds  when  they  are  picked.  The 
sucked  out  seeds  are  useless  for  either  sowing  or  for  oil  extraction,  and 
there  may  be  a  very  considerable  loss  from  this  cause.  If  the  boll  is 
open  and  the  insects  congregate  among  the  lint  to  reach  the  seeds,  the 
lint  may  be  stained  by  the  excreta,  and  this  form  of  damage  is  more 
readily  detected. 

Jleinedies. — Many  methods  of  dealing  with  this  insect  have  been 
suggested,  most  of  them  impracticable.  The  insect  being  larg-e  and 
vigorous,  insecticides  require  to  be  very  strong-  in  order  to  kill  it,  and 
this  damages  the  cotton  in  some  cases.  A  simple  method  of  destroying 
it  in  large  quantities  is  to  collect  the  insects  by  hand.  Each  cooly  has 
a  small  grain  winnow  (soop)  and  a  kerosene  tin  with  a  small  quantity 
of  kerosene.  The  insects  are  shaken  off  the  plant  with  a  smart  tap  into 
the  winnow ;  the  winnow  is  then  jerked  and  the  insects  fall  into  the 
lower  upturned  portion,  from  which  they  are  thrown  into  the  kerosene 
tin.  The  method  is  extremely  simple  and  readily  understood.  Very  few 
insects  escape  from  the  grain  winnow,  and  once  in  the  tin  their  death  is 
certain.  The  pest  is  so  readily  checked  by  this  means  that  it  need  never 
increase  excessively.     "Where  seed   for  planting  is  obtained  from  fields 


DUSKY    COTTON    ]MIO.  107 

infested  witli  tliis  bug-,  tlio  seed  should  ho  pickled  in  a  mixture  of 
cow-duuf,  clay  and  water,  and  then  thrown  into  water,  when  the  sound 
seed  sinksj  the  worthless  seed  floatiDg  (see  page  287).  The  red  bug-s  are 
infested  with  the  magg-ots  of  a  large  Tachiiiid  fly,  which  slowly  destroy 
their  host  and  thus  form  a  check  on  the  increase  of  the  bug. 

The  insect  is  common  throughout  the  plains,  in  the  jungle  and  in  the 
fields.  It  hibernates  in  many  parts  of  India  where  the  temperature  falls 
considerably,  and  is  found  in  hiding  as  an  imago  during  the  cold  weather. 
Where  the  climate  is  suitable  it  is  active  throughout  the  year. 

The  Dusky  Cotton  Bug.i 

This  insect  is  well  known  as  a  pest  to  cotton  in  many  parts  of  India. 
Though  small  and  insignificant  in  appearance,  its 
presence  in  great  numbers  in  the  open  bolls  of  cotton 
has  brought  it  into  notice.  It  has  been  reported  as 
sucking  green  bolls  and  injuring  the  lint  and  seed. 
The  insect  is  found  upon  the  cotton  plant,  especially 
in  the  bolls  that  open  prematurely  after  they  have 
been  eaten  by  the  boll-worm.  Large  numbers  of  small 
brown  insects  run  out  of  such  bolls  when  they  are 
handled  and  either  fall  to  the  g'round  or,  if  they  are 
full  grown,  fly  away.  ^ig.  126. 

The  life  history  in  the  cotton  boll  is  very  simple.     Dusky  Cotton  Bug. 

The  eggs  are  laid  in  the  lint   close  to  the  seed  :  each       A^^''^^i^^f\ . 
o°  '  [rrom  Distant,) 

Qgg  is  cigar-shaped,  about  one  mm.  long-  (^^sth  inch), 
of  a  brig'ht  yellow  colour,  when  first  laid.  They  are  laid  in  batches  of 
G  to  10  at  a  time,  and,  egg*-laying  extends  over  some  weeks.  Before 
hatching  the  egg  turns  a  bright  orange  and  the  emerging  insect  is  the 
same  colour.  The  newly-hatched  insect  is  about  yV^^  inah.  long,  with 
three  pairs  of  legs,  the  usual  four- jointed  antennae  and  an  enormous 
proboscis  which  stretches  from  the  head  to  beyond  the  end  of  the  tail. 
"With  this  it  is  able  to  pierce  the  cotton  and  extract  food  from  within 
the  seed.  During  the  next  week  it  grows  larger,  shedding  its  skin  at 
short  intervals  to  allow  of  expansion.  The  colour  gradually  alters  to  a 
deep  reddish  brown,  darkening  at  each  moult.  At  the  fourth  moult 
the  wings  appear  as  small  growths  on  the  upper  side  of  the  body.  At 
the  fifth  moult  the  wings  are  large  but  not  fully  developed,  appearino' 
in  their  full  size  after  the  sixth  moult  when  the  insect  is  mature.  The 
perfect  insect  is  nearly  black,  one-sixth  of  an  inch  in  length,  with  the 

'  5.  Oxycarosnus  latus.    Kir^y.     (Lygajida).) 


108  PESTS  OP  THE  COTTON  PLANT. 

transparent  wing-s  folded  over  the  back.  The  female  is  slightly  larger 
than  the  male  but  otherwise  outwardly  similar. 

The  whole  period  from  the  egg  to  the  perfect  insect's  emergence  is 
twelve  days.  The  mature  insects  lay  eggs  and  then  die.  They  may 
live  for  many  weeks  before  they  lay  eggs,  and  if  food  for  their  young  is 
not  available  they  wait.  Probably  they  pass  the  dry  weather  in  the 
adult  condition  if  no  food  is  available  for  them,  as  they  may  be  found  on 
the  plants  of  cotton,  etc.,  at  different  times  of  the  year.  In  the  cotton 
season  their  increase  is  rapid,  the  eggs  being  laid  in  the  cotton  bolls. 
At  other  times  they  will  lay  eggs  in  the  pods  of  the  bhindi  (Hibiscus 
esculfinfus)  and  possibly  of  other  malvaceous  plants,  or  wait  until 
egg-laying  becomes  possible. 

The  amount  of  destruction  caused  by  these  insects  varies  with  cir- 
cumstances. Where  there  is  abundance  of  worm-eaten  bolls,  the  insects 
live  in  these  bolls,  which  open  early.  They  are  then  credited  with  the 
damage  done  by  the  boll-worm,  as  they  are  the  only  insect  found  when 
the  boll  is  picked.  The  actual  destruction  to  the  crop  in  this  case  is 
small.  Where  there  are  no  bolls  attacked  by  worm,  they  attack  the 
bolls  as  they  open  and  are  responsible  for  damage.  The  seeds  are  sucked, 
the  lint  is  dirtied,  and  they  increase  very  rapidly  in  such  bolls. 

The  simplest  method  of  treating  them  is  to  shake  them  off  the  bolls 
into  a  vessel  containing  water  and  a  small  quantity  of  kerosene.  The 
early  ripening  bolls  contain  them  in  great  numbers,  and  by  shaking  these 
bolls  over  a  tin  pot  of  kerosene  and  water  they  will  be  killed  in  large 
numbers.  Worm-eaten  bolls,  with  the  insects  inside,  may  be  picked  off 
and  removed  in  a  bag.  There  would  be  a  far  smaller  number  of  the  insect 
in  cotton  fields  were  this  done,  and  the  method  of  testing  cotton  seed 
(page  287)  should  be  applied  to  seed  from  infested  fields.  This  method  of 
picking  off  and  shaking  the  bolls  may  be  tedious  and  long,  but  it  is  the 
only  practicable  method  as  a  rule.  On  farms  the  work  can  be  better  done 
with  a  spraying  machine.  It  is  extremely  important  to  check  the  pest  at 
the  outset  when  it  is  breeding  in  the  first  opened  bolls,  and  very  much 
better  cotton  will  be  obtained  w^hen  the  cultivator  takes  an  interest  in  his 
cotton  pests  and  attempts  to  check  them.  What  is  said  about  testing  cotton 
seed  infested  with  Red  Bug  applies  also  to  seed  sucked  by  the  Dusky  Bug. 

The  pest  is  generally  distributed  in  the  plains,  though  rarely  abuitdant. 

The  Cotton  Leaf  Hopper.^ 

Among  the  common  insect  pests  of  cotton,  the  least  noticeable  is 
a  tiny  green  fly,  which  lives  on  the  cotton  leaves  and  flies  or  leaps  out 

»  82.    (J^ssidse.) 


COTTON   LEAF   HOPPEli.  109 

wiien  tlie  plant  is  shaken.  It  is  distinct  from  the  cotton  aphis  since  it  is 
veiy  active,  both  leaping-  and  flying- ;  when  it  is  plentiful,  great  numbers 
leap  from  the  cotton  plants  when  they  are  shaken  or  disturbed,  and 
this  is  the  simplest  way  in  which  to  detect  the  pest.  The  insect  belongs 
to  the  family  Jassida,  leaf  hoppers,  of  which  great  num- 
bers live  in  g-rass  or  almost  any  veg-etation ;  they  are  so 
small  as  to  escape  notice.  The  eg-gs  are  laid  in  the  tissues 
of  the  plant,  and  the  young-  that  hatch  are  similar  to  the 
full  grown  insect  but  wingless  and  smaller.  The  food 
consists  of  the  sap  of  the  leaves,  which  is  extracted  by 
means  of  the  slender  sucking  apparatus  which  forms  the 
mouth.  The  species  attacking  cotton  may  be  found  at 
all  times  of  the  year  both  in  grass  and  in  cotton.  Healthy 
vigorous  cotton  is  less  attacked  than  weak  unhealthy  cotton  ;        c-      -lo*- 

°  .  ,  tlG.  127. 

fewer  insects  are  to  be  found  on  vigorous  cotton  plants      coUon  Leaf 
and  the  leaf  hoppers  prefer  to  live  on  unhealthy  plants.     As        Sopper. 

.  ,         ,  PIT  ii.  •  {Magnified.) 

a  pest,  the  insect  has  been  found  only  on  cotton  growing 
under  unsuitable  conditions.  In  190i,  there  were  plots  of  healthy  cotton 
and  of  cotton  that  had  suffered  from  the  drought,  growing  side  by  side  in 
one  of  the  Government  experimental  farms.  Few  insects  could  be  found 
in  the  former,  whilst  the  latter  contained  enormous  numbers.  Tliis  was 
observed  also  in  Behar,  where  cotton  was  being  tried  and  suffered  heavily 
from  the  excess  of  moisture.  The  absolutely  backward  cotton  was 
infested,  the  vigorous  cotton  was  practically  free.  As  a  pest  then  it  will 
be  found  attacking  weak  cotton;  the  result  of  the  attack  is  that  the 
leaves  curl,  become  discoloured^  wither  and  fall  off. 

The  pest  is  apt  to  kill  cotton  that  is  struggHng  against  bad  conditions. 
It  appears  to  attack  the  larger  leaved  tree  cottons  and  American  varieties 
more  than  the  smaller  leaved  Broach-Deshi  and  Goghari  cottons,  but  will 
attack  every  variety  if  the  plants  are  in  bad  condition.  Evidently  this 
insect  cannot  rank  as  a  general  pest  since  it  will  not  attack  healthy 
cotton.  It  is  a  serious  pest  in  the  experimental  farnis*  where  introduced 
varieties  are  being  acchmatised  ;  it  has  also  been  a  pest  to  many  varieties 
of  the  American  and  Egyptian  cotton  grown  in  Behar  during  the  wet 
months.  It  has  been  successfully  checked  by  spraying  with  crude  oil 
emvdsion,  at  the  rate  of  1  in  50  of  water.  An  acre  of  badly  infested 
Goghari  cotton  treated  with  a  Success  Knapsack  machine  requires  100 
gallons  of  wash,  costing  Rs.  •'3-8,  and  one  day  for  application.  A  large 
amount  of  wash  must  be  used  since  it  is  desired  to  spray  the  insects  as 
they  come  out  of  the  plants  in  a  cloud,  and  not  to  spray  the  plant  alone. 
This  is  a  simple  and  effective  remedy ;  no  other  appears  Hkely  to  be  so 


no 


tfiSTS    Of    THE    COTTOX    PLAJ^T. 


successful.  AVliere  it  is  necessary  to  lielp  a  struggling  crop  tlirougK  a 
bad  season,  spraying  of  this  kind  will  be  a  necessity.  When  the  plants 
become  stronger,  they  T^'ill  not  show  the  disease,  and  will  not  be  impaired 
by  it. 

This  insect  is  known  from  Gujarat,  Nagpur,  Cawnpore,  Lyallpur  and 
Behar  at  the  present  time.  It  will  probably  be  found  wherever  cotton  is 
grown  in  India. 

Cotton  Aphis. 

Small  sucking  insects  found  in  abundance  on  the  shoots  and  leaves 
of  the  cotton  plant ;  they  are  about  one-twentieth  of  an  inch  long, 
coloured  in  dull  yellow  or  black,  and  have  two  short  processes  projecting 
from  the  upper  surface  of  the  abdomen.  This  pest  is  one  of  the  common 
plant-lice  discussed  in  a  later  section  and  has  a  similar  life  history.  The 
colonies  found  on  cotton  consist  of  female  insects,  which  produce  living 
young.  There  is  no  metamorphosis ;  the  young  are  born  alive  and  are 
all  females.  After  a  few  days  they  in  turn  commence  to  produce  living 
young  ones.  Two  kinds  of  females  may  be  seen,  unwinged  yellowish 
ones  and  winged  black  ones.     The  latter  fly  from  plant  to  plant  and 


Fig.  128. 

Winjed  female.      {3Iagnified  ten  times.) 

Spread  the  pest  over  the  field.  As  a  rule  the  young  and  the  unwinged 
females  move  but  little,  feeding  in  compact  colonies  on  the  underside  of 
the  leaves  or  on  the  shoots ;  they  extract  the  sap  frcm  the  plant,  making 
it  weak  and  sickly.  The  insect  appears  in  the  rains  and,  if  cotton  plants 
are  available,  remains  on  them  until  the  weather  becomes  very  dry,  often 
until  the  end  of  the  cold  weather*  In  cloudy  weather  the  ringed  ones  fly 
far  over  the  field  and  found  nelv  colonies.     Hence  it  is  that  after  the 

^B.  i4j}liis  gosst/fii-     Glov.     (ApLicla:) 


fcd'rl'ON  APHi^. 


ill 


cloudy  Avi'atiicr,  aphis  becomes  move  a])undaiit  and   suddenly  appears    over 
larg-e  ai'eas. 

Plant-lioe  excrete  a  sugary 
liquid,  wliicli,  falling-  on  the 
leaves  below,  dries  to  a  sticky 
coating.  This  appearance  on 
the  leaves  is  a  sign  of  the  pest 
and  is  familiar  to  cultivators. 

Many  insects  attack  the 
cotton  aphis  and  are  very  im- 
portant checks  upon  it ;  these 
are  described  in  a  later  section 
under  beneficial  insects.  These 
insects  should  be  familiar  to  all 
who  grow  cotton  and  should  not 
be  destroyed  in  error  as  injuri- 
ous insects. 

The  treatment  for  cotton 
aphis  lies  in  spraying  with  a 
contact  poison,  doing  tliis  when 
the  first  colonies  appear  on  the 
cotton  and  not  delaying  until 
with  cloudy  weather  they  spread 
over  the  whole  field.  If  culti- 
vators Avere  familiar  with  aphis 
and  checked  it  as  soon  as  they 
first  saw  it,  it  would  never 
become  so  serious  a  pest. 
Without  this,  large  areas  may  in  cloudy  weather  become  aiffiected,  and 
though  the  pest  is  principally  one  on  farms  and  experimental  cultivation, 
it  is  also  an  important  field  pest. 


Fig.  129. 
CoHon  Aphis,  tcint/ed  femalo. 
{^Magnijied  jifleen  times,) 


Minor  Pests. 

There  are  a  iiumbei'  of  insects  which  attack  cotton  casually,  doing  as 
ft  rule  no  harm  but  possibly  injurious  in  unusual  seasons.  The  Wliite 
"Weevil  ^  is  a  small  beetle,  of  a  dull  Avhiie  colour,  found  upon  the  leaves  of 
all  varieties  of  the  cotton  plant  almost  throughout  the  year.  It  bites  the 
leaves  of  the  plant,  eating  in  from  the  edge.     It  is  most  conspicuous  from 

^  JIi/UocerKs  inactdosia:     Des  L.     (Curculionidii'.) 


in 


tUSTS    OF   THli   COTTON    PLANT. 


July  to  October,  but  has  been  found  at  all  times.  The  life  history  is 
completely  unknown  and  is  apparently  not  passed  in  the  cotton  plant. 
Special  treatment  is  not  required 
for  this  pest,  which  is  easily  de- 
stroyed by  shaking-  it  off  the 
plant ;  it  has  a  habit  of  falling-  to 
the  ground  Avhen  disturbed  and 
"shamming  dead.^^  The  Green 
Weevil  ^  is  also  a  pest  of  cotton, 
eating  the  leaves  in  the  same 
manner.  This  insect  is  larger 
than  the  Wliite  Weevil,  of  a 
dark  colour  but  clothed  in 
metallic  green  scales,  which  give 
it  a  peculiarly  brilliant  aj^pear- 
ance.  It  is  common  in  Behar 
and,  like  the  White  Weevil,  is 
found  also  on  bhindi,  maize  and 
other  crops.  The  Cotton  Cater- 
pillar^ is  a  green  caterpillar, 
which  is  found  on  the  cotton  leaf  ; 
it  walks  after  the  fashion  of  the 
true   looper  caterpillars,  hunching- 


/ 

/ 

JH^   ,t    U,    ?<    '  tad^^              V 

.^^BS'li/'                  >'•*«'*  i^Bik 

j^  '^BS^^  >"  ~       .•yJB  \^ 

\ 

/ 

)            J                   \^ 

\ 

Fig.  130. 

Cotton  Aphis,  iinwinged  female, 
{Mag nijied  fifteen  times.) 


up  its  body  at  every  step,  but  is  actually  a  "  semi-looper  ^^  with  three 
pairs  of  sucker-feet  on  the  abdomen.  The  caterpillar  is  marked  with 
fine  white  lines  and  grows  to  a  length  of  one  inch  and  a  quarter.  It  eats 
the  leaf,  making  large  holes,  and  finally  pupates  by  turning  over  the 
edge  and  folding  it  down.  The  moth  emerges  after  eight  days.  This 
pest  is  not  common,  is  found  only  during  the  rains,  and  feeds  also  on  bhindi 
and  other  plants. 

Another  semi-looper  found  on  cotton  has  but  two  pairs  of  sucker- 
feet  on  the  abdomen  and  a  swelling  on  the  upper  surface  of  the  body  on 
the  first  abdominal  segments  and  the  tail.  It  feeds  on  the  cotton  leaf 
and  eventually  comes  out  as  a  white  moth  3  with  dark  markings.  Like 
the  last  this  is  not  usually  injurious  but  is  likely  to  be  mistaken  for  a 
serious  pest.  '^ 

Hairy  caterpillars  which  at  times  ravage  large  areas  of  crops  also 
attack  cotton  and  may  do  much  harm.     In  Behar,  the  common   hairy 

^  188.  Asiycus  lateralis,  F.     (Curciilionifla\) 
2  115.  CosmopMla  erosa,    HuLn.     (Noctuidse.) 
^  162.  Taraclie  catena.     Sow.     (Noctuidte.) 


MINOR   COTTON   PESTS.  113 

caterpillar  ^  is  found  in  abundance  on  cotton  throughout  the  rains  if  other 
crops  fail  it,  and  this  applies  also  to  the  Hairy  Caterpillar  of  Gujarat." 

The  very  common  Red  Leaf  Beetle  ^  is  found  on  cotton  but  does  no 
harm.  The  Cotton  Mealy  Bug  is  a  iDeeuliar  species  which  is  found  on  the 
top  of  the  shoot ;  the  shoot  swells  and  twists,  forming  a  hard  gall-liko 
mass  and  stunting  the  growth  of  the  plant.  Only  some  varieties  of 
indigenous  cottons  are  affected  and  the  pest  is  not  widely  spread.  It 
requires  to  be  destroyed  by  picking  the  twisted  shoots,  or  by  spraying,  as 
it  interferes  with  the  normal  growth  of  the  plant. 

The  large  spotted  grasshopper  *  is  one  of  the  few  grasshoppers  that 
is  commonly  found  feeding  on  this  plant.  Germinating  cotton  suffers 
from  the  ground  grasshoppers  and  weevils  which  attack  germinating 
seeds  as  they  push  leaves  above  the  ground  (see  page  220).  The  ryot  sows 
his  cotton  so  thickly  that  no  damage  is  done  as  a  rule,  but  tree  cottons 
and  other  cottons  sown  far  apart  will  be  eaten  if  the  field  is  very  clean. 
It  is  advisable  to  sow  some  such  crop  as  maize  between  the  cotton  or  to 
leave  the  final  weeding  till  the  cotton  has  formed  two  leaves,  as  the  insect 
then  has  other  food  and  spares  the  cotton. 

1  136.  Diacrisia  obliqua.    Wlk.     (Arctiidae.) 

2  220.  Amsacta  lactinea.     Cr.    (Arctiidae.) 

^    11.  Aulacophorafoveicollis.     Kiist.     (Chrysomelida».) 
*    49.  Acridium  ceruginostim.     Burm.    (Acridiida;.) 


CHAPTER  IX. 

PESTS  OF  RICE  AND  WHEAT. 

THE  area  occupied  by  these  crops  is  so  large  that  it  has  not  been  possible 
to  study  adequately  their  pests  in  detail.  The  four  chief  insects 
that  attack  rice  and  one  that  attacks  wheat  are  described.  There  are 
in  addition  many  insects  which  appear  occasionally,  especially  those 
caterpillars  which  attack  rice.  In  general  these  are  not  formidable  nor 
sufficiently  abundant  to  make  any  impression  on  the  very  large  area  of 
this  crop.  The  method  recommended  for  dealing  with  the  Rice  Grasshop- 
per should  in  many  cases  give  good  results  against  these  Rice  Caterpillars. 

Wheat  appears  to  sufPer  from  few  pests ;  the  stem-borer  is  a  specific 
pest  of  wheat,  cane,  etc.  The  wheat  aphis  is  a  serious  pest  dealt  with 
under  the  heading  "Green  Fly  and  Plant  Lice"  (page  237).  Young 
wheat  suffers  from  ground  insects  as  do  other  young  rabi  crops.  Many 
pests  of  wheat  probably  remain  to  be  discovered  and  any  extension  of  the 
area  under  this  crop  to  fresh  districts  will  probably  produce  new  pests. 


The  Rice  Hispa  .^ 


A  small  blue-black  beetle,  covered 
the  leaves  of  rice;  an  infested  field 
becomes  yellow,  the  leaves  dying  and 
the  plants  withering.  This  pest  is 
a  familiar  one  to  cultivators  of 
Bengal  and  Assam,  known  by  many 
vernacular  names.  The  small  flattened 
beetle  is  easy  to  recognise  and  the 
peculiar  effects  of  the  attack  are  fairly 
characteristic. 

Life  Histori/. — The  eggs  are  laid 
singly,  each  q^^  being  inserted  in 
the  tissue  of  the  leaf,  almost  exposed 
and  easily  visible.  The  egg  is  oval, 
about  one-thirtieth  of  an  inch  long, 
and  when  in  the  leaf  is  detected  by  the 
white  spot  and  the  bvilge  in  the  slit 
epidermis.  It  is  laid  in  the  upper  part 
of  the  leaf,  not  far  from  the  point.   The 


with    spines,    which    feeds    upon 


Fig. 131. 
Tha  Rice  Rispa.  {Magnified  seven  times.) 


^  41.  Hispa  mnescens.    Baly.    (Chrysomeliclae.) 


RICE    HISPA.  115 

egg  hatches  to  a  small,  flattened  grub,  with  three  pairs  of  legs,  which  lives 
inside  the  leaf  between  the  upper  and  lower  epidermis.  The  gnib  is  white  or 
3'ollow  with  black  markings,  very  flattened,  the  first  three  segments  broader 
than  the  abdomen.  It  feeds  on  the  tissue  inside  the  leaf,  eating*  it  away 
and  producing'  a  large  yellow  spot.  The  grub  is  found  by  searching  for 
such  yellow  spots,  and  the  insect  may  be  seen  inside  if  a  spotted  leaf  is 
held  up  to  the  light.  The  grub  when  fidl  grown  transforms  to  the  pupa 
inside  the  leaf  and  emerges  as  the  beetle.  The  whole  life  history  is  passed 
within  the  leaf  until  the  mature  beetle  comes  out  to  fly  about.  It  feeds 
upon  the  leaf,  eating  away  the  epidermis  and  causing  further  destruction. 

The  insect  principally  attacks  the  young  plants,  feeding  and  laying 
eggs  npon  the  tender  green  leaves  of  the  seedling  or  of  the  newly  trans- 
planted rice.  It  is  injurious  to  rice  in  the  seed-bed  and  shortly  after 
transplanting,  the  older  rice  being  less  attacked  and  not  injured. 

Wild  grasses  are  the  normal  food-plants  and  the  beetle  flies  from  the 
waste  lands  or  jungle  to  attack  the  early  rice.  In  some  parts  of  Bengal 
it  is  reported  to  come  in  enormous  numbers,  blackening  the  fields  on 
which  it  settles  and  causing  a  wholesale  destruction  of  the  crop.  Like  the 
rice-bug  it  is  dependent  upon  moist  conditions  and  attacks  rice  that  is 
submerged  in  preference  to  rice  on  higher  land  from  which  the  water  has 
been  run  off  ;  this  is  the  only  remedy  applied  by  cultivators,  who,  when 
possible,  let  the  water  out  in  the  hope  that  the  insect  will  leave  their  fields. 

The  insect  spends  the  winter  as  a  beetle  in  waste  lands  and  grass- 
lands. The  season  at  which  it  appears  depends  upon  the  sowing  of  rice 
and  the  climate,  but  lies  between  April  and  November. 

Preventive  measures  for  this  pest  must  be  based  upon  local 
conditions  :  where  the  pest  is  known  to  come  from  a  particular  place,  it 
may  be  possible  to  destroy  it  there,  as,  for  instance,  in  the  wild  grasses 
in  which  it  lives  before  the  rice  is  sown,  or  the  sowing  and  transplanting 
of  rice  may  be  varied  to  prevent  the  pest  attacking  it.  In  seed-beds  the 
beetle  can  be  destroyed,  and  if  the  seed-bed  is  watched  when  the  beetle 
is  likely  to  attack  it,  egg-laying  can  be  prevented.  When  the  beetles 
come  in  great  number  the  ordinary  bag  is  sufficient  to  sweep  them  up 
with,  and  the  cultivator  is  quite  capable  of  using  his  dhoti  or  other 
cloth  for  the  purpose.  Any  concerted  action  designed  to  prevent  egg- 
laying  and  worry  the  insect  is  what  is  required,  and  what  is,  in  India, 
so  diflfjcult.  When  once  egg-laying  has  been  performed  nothing  can  be 
done  but  to  wait  for  the  emerging  beetles  and  destroy  them.  The  use  of 
arsenical  insecticides  is  valuable  as  a  poison  for  the  beetle,  but  is  ineffective 
against  the  egg  or  larva.  There  is  probably  little  scope  for  the  use  of 
lead  arseni9,te,  since  it  will  not  stand  rain  and  washes  off.     There  is  also 

i8 


116 


PESTS   OF   RTCE   AND  WHEAT. 


little  scope  for  the  use  of  smoke.  Smoke  is  advisable  as  a  means  of 
checking  the  insects  when  they  first  come  as  it  drives  them  out  of  the 
field ;  it  has  no  further  effect,  kills  nothing  and  is  only  a  temporary  device 
to  frighten  away  the  incoming  beetles.  No  specific  remedy  can  be 
recommended  against  this  pest ;  the  life  history  is  so  safeguarded  that 
there  is  no  obvious  point  of  attack,  and  reliance  must  be  placed  upon 
preventive  measures  based  solely  on  local  conditions  and  aimed  at 
destroying  the  insect  in  its  breeding  grounds,  securing  an  earlier  or  later 
growth  of  rice  to  circumvent  the  beetle,  or  making  the  conditions 
unsuitable  to  the  existence  of  the  insect.  The  only  available  direct 
remedy  is  to  destroy  the  beetles  with  bags,  systematically  working 
through  the  fields  and  sweeping  them  clean  ;  this  must  be  done  promptly 
as  soon  as  the  beetles  come,  and  must  be  thorough. 

It  has  been  found  that  certain  softer-leaved  varieties  of  rice  are  more 
attacked  than  rough  hard-leaved  varieties  growing  side  by  side,  and  in 
these  cases  the  ryot  has  a  remedy  to  hand.  The  higher  priced  soft  variety 
is  grown  at  a  risk,  when  the  rough  variety  might  afford  an  almost  certain 
full  yield. 

The  Rice  Bug.^ 

A  slender  green  insect,  found  flying  in  the   rice-fields,  which  sucks 

the  sap  of  the  developing  ears 
and  causes  them  to  turn  white. 
The  insect  has  an  aromatic 
odour,  suggesting  geraniums, 
and  may  be  found  in  rice-fields 
when  the  grain  forms.  The 
characteristic  symptom  of  the 
pest  is  the  whitening  ears,  a 
whole  field  often  turning 
colour  in  this  way. 

The  insect  is  a  typical 
bug,  with  no  metamorphosis. 
The  eggs  are  laid  in  the  jungle, 
as  also  in  the  rice  crop  coming 
into  ear.  Each  egg'  is  oval, 
somewhat  flattened,  nearly 
black  and  very  seed-like.  They 
are  laid  separately,  in  clusters 
of  four  to  ten,  on  the  leaves. 


Fia.  132. 
The  Rice  Stiff.     (Maffnijled  twice.) 


*103.  Leptocorisa  varicornis.     F,     (Coreidje.) 


RICE   BUG. 


117 


off  aud  liberatins!:  the  bug-. 


Tliey  are  quite  easily  seen,  the  cg-gs  forming'  a  conspicuous  object  on  the 

"•recn  leaf.     When  ready,  the  eg'g-  opens,  the  delicate  inner  membrane  and 

part  of  one  end    of   the   outer  shell  coming 

The  little   bugs  are    most    quaint 

insects,  all  legs  and  feeler?,  with  a 

slender  green  body.     The  antennae 

are    banded    in   black,  white  and 

brown,  the  legs  black,  all  extremely 

long  in  comparison  with  the  tiny 

green     body.     The     proboscis     is 

very    long,    reaching    beyond  the 

insertion  of  the  hind  legs. 

At  each  moult  the  insect  grows 

larger,  the  body  remaining  green. 

Wings     are      formed      gradually. 

When  full  grown  the  insect  is  about 

two-thirds   of   an    inch    long,  the 

wings  folded  over  the  abdomen,  the 

body  green  with  a  tinge  of  straw 

colour,  the  antennae  parti-coloured. 

It  flies  actively  and  may  be  readily  Fig.  133. 

made  to  fly  out  of  the  field.  ^^^*  ^/  '^"  ^'''  ^'^^-   (^''^'^^J^''^  *'"^''-^ 

This   bug    feeds   upon  ripening   seeds;   it   will    attack   rice,    small 

millets,  grasses  and  other  plants  as  the  seeds  form  and  fill  with  milky 
juice.  Sama  [Panicum  Jrumentacenm)  is  a  favourite  food,  and  the  bug  s 
normal  food  is  the  wild  grasses  in  the  jungle  and  waste  lands.  Though 
common  in  cultivation  during  the  rains,  it  breeds  only  when  a  crop  is 
ripening  and  food  is  plentiful.  Then  the  eggs  are  laid  on  the  leaves  of 
the  plant  and  the  young  find  abundance  of  food. 

Cultivators  know  the  pest,  which  has  many  vernacular  names,  but 
do  nothing  to  check  it.  It  is  prevalent  in  Burma,  Assam,  Bengal,  the 
United  Provinces  and  Madras,  practically  throughout  the  rice  districts  of 
India.  In  other  parts  of  India  it  is  to  be  found  where  the  conditions 
are  suitable ;  it  extends  to  Ceylon,  the  Malay  Peninsula,  Malayan  Archi- 
pelago and  China.  As  the  winged  form  is  fairly  active,  it  can  be  driven 
from  the  rice-fields  with  little  effort.  The  unwinged  young  when  dis- 
turbed simply  fall  to  the  ground  or  to  the  surface  of  the  water,  whence 
they  climb  u])on  the  plants  again.  There  is  no  easy  means  of  checking 
it,  but  if  sufiicient  trouble  is  taken  and  a  large  area  treated,  the  insect  can 
be  destroyed.  Ihe  simplest  method  is  to  draw  a  bag  through  the  rice, 
simply  running  it  over  the  plants.     Two  coolies  can  easily  manage  a  bag 


118 


PESTS    OF    RICE    AND    WHEAf. 


eight  feet  wide  and  three  feet  deep  with  the  opening  three  feet  high. 
Two  bamboos  keep  open  the  sides  of  the  mouth  and  the  bag  can  be 
drawn  tight  and  rapidly  run  over  the  rice,  brushing  through  the  upper 
half  of  the  plant.  The  winged  and  unwinged  are  caught  if  the  bag  is  at 
once  twisted  up  at  the  close  of  each  run  and  a  very  large  area  can  be 
rapidly  swept.  The  method  is  useless  without  co-operation,  as  a  whole 
area  must  be  swept  clean  or  the  bugs  wander  in  again. 

When  the  flying  bugs  first  come  in,  the  mere  dragging  of  a  rope 
through  the  crop  drives  them  out  again,  and  a  little  systematic  worrying 
of  this  kind  sends  them  back  to  the  jungle.  A  remedy  for  this  pest  used 
in  South  India  and  Ceylon  is  to  smear    a   paddy  winnow  with  sticky 

fruit  juice,  fix  it  to  a  pole  and  wave  it 
in  the  fields.  The  insects  stick  to  the 
winnow  if  struck. 

A  common  hand  net  is  more  efficacious 
and  just  as  easily  made,  and  in  actual 
j)ractice  the  bag  is  better  still.  This 
method  however  appeals  to  cultivators  and, 
if  vigorously  carried  out,  does  destroy  and 
drive  away  the  pest. 

In  Bengal  the  rice- fields  are  found  to 
contain  numbers  of  very  active  blue 
beetles,  marked  with  six  white  spots, 
which  feed  upon  the  rice  bug.  This  is  the 
Six-spotted  Tiger  Beetle,^  a  very  valuable 
predaceous  l^eetle  which  gathers  in  bug -infested  rice-fields  and  keeps  the 
bugs  in  check.     Another  check  is  a  small  parasite  found  in  the  eggs. 


FiCx.  134. 

The  Six-spotted  Tu/er  Beetle 

that  preys  on  the  Rice-Buj. 


The  Rice  Stem  Fly.2 

The  first  symptom  of  this  pest  is  the  withering  of  the  upper  half  of  the 
plant,  the  main  stalk  bending  over  from  a  point  some  distance  above  the 
ground.  The  upper  part  withers  and  the  main  stem  dies.  If  such  a 
stalk  is  split  up  the  middle,  the  maggot  or  pupa  of  the  insect  will  be 
found. 

Very  little  ia  known  of  the  occurrence  of  this  insect  in  India,  as  it 
has  been  reported  very  seldom.  The  maggots  are  foun<l  in  the  shoots 
of  rice ;  they  feed  on  the  sap  and  produce  a  deformity  and  weakening  of 
the  stem.  The  stem  eventually  falls  over  at  the  weak  point.  The 
maggot  transforms  to  the   pupa   inside   the    stem,   the   pupa  being  a 

'  187.  Cicimlela  sexpunclata.  L   (Ciciadeliclae.)  |     *    14.  (Muscitla3  acalyptratiE.) 


inCK   GEASSHOPPER. 


119 


small  brown  object  like  a  flax  seed.  No  specimens  have  yet  been 
reared  in  India  under  observation  and  the  details  of  the  life  history  are 
not  known. 

The  insect  has  been  found  or  reported  from  a  few  scattered  local- 
ities in  the  plains  of  India  and  is  probably  far  more  widely  spread,  gen- 
erally escaping-  notice.     It  is  attacked  by  a  hymenopterous  parasite. 

Rice  is  not  the  only  food-plant  sama  being  an  alternative  one. 

No  general  methods  of  treatment  are  available  against  such  a  pest; 
and  preventive  measures  based  upon  local  conditions  can  alone  be 
effective.  Some  good  would  be  done  if  all  affected  plants  were  destroyed, 
but  no  remedial  measures  can  cheek  such  an  insect.  It  will  be  necessary 
to  devise  measures  based  on  supplying  the  insect  with  a  trap  food-plant, 
such  as  sowing  an  early  trap  crop  or  destroying  it  in 'a  particular  plant  or 
crop  at  one  special  period  of  the  year.  It  may  be  possible  to  find 
immune  varieties  of  rice,  or  to  make  such  changes  in  the  agricultural 
practice  of  affected  districts  as  will  baffle  the  pest,  as,  for  instance,  sowing 
earlier  or  later.  It  is  not  likely  that  any  good  will  be  done  without  care- 
ful study  and  some  experiment,  and  what  is  found  usefid  in  one  locality 
will  not  be  likely  to  suit  another. 

Wood-Mason  has  recorded  an  insect  ^  allied  to  the  Hessian  Fly 
which  attacks  rice  in  a  somewhat  similar  manner.  This  is  a  distinct 
pest,  of  which  practically  nothing  is  yet  known.  Either  insect  is  likely 
to  be  found  in  rice. 

The  Rice  Grasshopper.^ 

Among  the  most  familiar  rice  pests  is  a  large  grasshopper,  green  ol* 
dry  grass  colour,  which  lives  in  the  rice-fields,  becoming  mature  about 


Fig.  135. 
The  nice  Grasshopper.     Aornial  form. 


'   Cecidomyia  oryzee.     W.  M.     (Cecidomyiidac.) 
2  47.  Sieroglyplms furcifer .     Serv.     (Acridiidaj.) 


120 


PESTS   Ot   RlCE  AtJD   WHMT. 


Aug-ust  or  September.  It  is  easily  reeog-nised  from  the  fig-ure,  the  short 
wing's,  the  uniform  colour  and  the  indented  black  marks  on  the  thorax 
being  distinctive. 

The  life  history  is  passed  in  the  rice-fields  and  occupies  seventeen 
weeks.  The  egg's  are  found  embedded  in  the  soil,  in  the  fields  or 
embankments ;  each  egg  mass  is  a  hard  cylindrical  body,  about  half  an 
inch  long  with  one  end  rounded,  the  other  flat ;  the  eggs  inside  are 
densely  packed  in  a  hard  cement, 
and  the  outside  crust  consists  of 
cement  and  earth.  These  eggs 
hatch  after  the  first  heavy  rains 
and  the  small  active  insects  emerge  ; 
they  are  at  first  dark  coloured,  with 
a  green  dorsal  stripe,  but  later 
become  green.  The  little  insects  are 
very  active  aud  feed  on  the  growing 
rice.  They  undergo  the  usual  five 
moults  and  become  full  grown  in 
eight  to  ten  weeks.  The  imago  is 
found  in  two  forms  (figs.  135  and 


Fig.  137. 

E(f(f  Mass  of  Bice 

Grasshopper  to  show 

interior.  {Maffnijied  twice.) 


Fig.  136. 
Egg  Mass  of 
138),  one  with  the  long  wings,    the  -Kicc  Grasshopper 

other  with  short  imperfect  wings. 
As  the  insect  never  flies,  wings  are  apparently  useless.  After  mating  the 
eggs  are  laid  in  the  soil ;  this  takes  place  in  late  September  or  early 
October,  as  a  rule,  but  the  dates  vary  according  to  the  rains  and  the  sowing 
and  reaping  of  the  rice  crop.  This  grasshopper  is  found  in  grass-fields, 
in  damp  waste  lands,  in  rice-lands  and,  more  rarely,  in  sugarcane  fields. 
It  is  also  a  pest  of  cane,  aud  in  irrigated  cane-lands  there  may  be  an 
early  brood  of  the  pest,  the  eggs  hatching  when  the  land  is  irrigated  in 

March  or  April.  It  is 
injurious  principally 
by  devouring  the 
young  rice  crop  or  by 
eating  the  soft  grains 
of  rice  in  the  ear. 
A  useful  method  of 
dealing  with  thi§  pest 
was  worked  out  by 
Mr.  S,  Stockman  and 
Fig.  138.  l^^s    been    applied  in 

The  Rice  Grasshopper,  small  winged  form.  the  Central  Provinces 


MiNOli    IMCiB    PESTS. 


131 


and  Belg-aiiin.  It  consists  in  drag-giny-  a  net  tliroug'li  the  rice  to 
sweep  lip  the  insects ;  the  net  is  36  feet  by  7  feet,  weighted  at  one 
side,  with  ropes  on  the  bottom  to  drag"  it  by,  and  a  bamboo  to  hold 
lip  the  top.  Nino  men  drag  it  throug-h  the  field,  the  lower  edge 
below  Avater  sweeping  up  grasshoppers,  caterpillars,  and  other  insects. 
The  method  was  successfully  adopted  in  Belgaum  and,  where  the 
cultivators  work  together,  large  areas  of  rice-lauds  can  be  effectually 
cleared  of  the  pest. 

Attempts  to  destroy  the  eggs  during  the  cold  weather  have  failed, 
owing  to  the  difficulty  of  finding'  the  egg  masses,  which  are  buried  to  a 
depth  of  two  inches  in  the  soil. 

The  Rice  Grasshopper  is  common  throughout  the  plains  of  Bens^al, 
the  Central  Provinces,  parts  of  the  Bombay  Presidency  and  Mysore. 


Minor  Pests. 

A  mimber  of  insects  feed  upon  the  rice-plant  and  it  is  uncertain 
which  of  these  can  rank  as  pests.  Caterpillars  are  particularly  common 
and  a  number  have  already  been  reared  from  rice  but  only  rarely  found 
to  be  injuriously  numerous.  An  important  local  pest  is  the  "  beddi "  ^ 
insect  of  Bhandara  and  Kauara,  which  is  closely  allied  to  the  aqimtic 
caterpillar  ^  of  Burma.  The  work  of  these  is  apparently  identical ;  both 
eat  the  leaves  and  live  in  a  case  formed  of  a  leaf -blade  twisted  over  and 


Fig.  139. 
Butterflif  of  large  Rice  Caterpillar 


*  38.  Nymphula  depunctalis.     Guen.     (Pyralidse.) 
^  Nymphula  fluctuosalis.    Zell.     (Pyralidae.) 


l2^  PESTS    OF    RICE   AND    WUliAt. 

made  fast  with  silk.  The  caterpillar  is  a  serai-aquatic  one,  provided  with 
gills  for  obtaining"  air  from  water.  If  the  water  is  let  ont  of  the  fields, 
the  insect  is  less  destructive,  and  remains  by  day  on  the  wet  soil.  It 
pupates  in  its  leaf -case  and  the  moths  are  found  in  large  numbers  in  the 
affected  fields.^ 

Another  and  larger  caterpillar  that  folds  over  the  leaf  is  the  green 
caterpillar  of  a  butterfly.^  A  large  green  caterpillar,  distinguished  by 
having  two  large  processes  on  the  head,  is  the  caterpillar  of  the  butterfly  ^ 
reproduced  (fig.  139).  This  caterpillar  clings  tightly  to  the  leaf  and  is 
protected  by  its  cryptic  colouring.  The  larva  of  a  small  black  and 
yellow  moth*  twists  the  leaf -blade  into  a  shelter  and  feeds  within. 
Other  caterpillars  live  openly  on  the  rice  leaves,  and  it  is  not  unusual  to 
find  that  swarming  caterpillars  will  destroy  large  areas  of  this  crop  (see 
page  187).  One  species^  in  particular  appears  in  vast  numbers  on  the 
plants,  strips  the  leaves  to  the  mid-rib  and  spreads  rapidly  from  field  to 
field.  Against  these  pests,  the  bag  (page  72)  is  often  useful.  Branches 
of  trees  placed  in  the  fields  encourage  insectixorous  birds  which  can 
perch  there  in  the  intervals  of  making  a  meal  on  these  pests. 

Blister  beetles  attack  rice  when  in  flower  (page  206)  and  several 
cockchafers  have  the  habit  of  destroying  the  soft  grain  before  it  is  ripe 
(page  200). 

The  Wheat  Stem  Borer.« 

It  is  not  iTUcommon  to  find  the  stems  of  wheat  withering  prema- 
turely, the  plants  becoming  yellow  and  dying.  Such  plants  contain 
borers,  which  will  be  found  by  splitting  up  the  stems.  The  eggs  from 
which  these  borers  hatch  are  laid  in  clusters  on  the  lower  leaves  near  the 
stem ;  they  are  the  usual  small  white  rounded  eggs,  in  compact  clusters 
of  twenty  to  thirty.  The  caterpillars  bore  into  the  stem  of  the  wheat 
plant,  feeding  in  the  centre  of  the  stem.  The  plant  dies,  withering  up, 
and  new  shoots  are  formed  at  the  base.  The  full  grown  caterpillar, is 
about  one  inch  long,  smooth,  with  a  brown  head  and  a  rather  pinkish 
body  j  it  is  not  the  dull  white  of  most  borers,  biit  tinged  with  pink  and 
thus  easily  recognised.  The  chrysalis  is  found  in  the  wheat  stem.  The 
moth  is  the  colour  of  dry  grass,  similar  in  appearance  to  many  other 
moths  which  live  in  g-rasses.  '^ 

^  Report  of  Eatiram  Khamparia,  Entomological  Assistant,  Central  Provinces. 
2     30.    Chapra  mathias.     Fabr.      (Hcsperiidae.) 
^  236.   MeJaniiis  ismene.     Cram.      (Nymphalida?.) 

*  48.   Cnaphalocrocis  wedinah's.  Gueii.     (Pyralidir.) 

*  235.  Spodopfera  mauriUa.     Boiwd.     (NoctuidfE  ) 

*  91.  Nonagria  uniformis.     Ddgn.     (Noctuida;.) 


WHEAT    STEM    BOllEU. 


1^3 


Fig.  140. 
Wheat  Stem  Borer.     (Magnified  twice.) 


This  species  has  been  found  duriug"  the   cold  weather  in    wheat    and 

during-  the  hot  weather  and 
rains  in  sorg-hum,  rice  and 
cane.  It  is  a  common  cane 
pest  in  Behar,  and  an 
important  wheat  pest  in 
Gujarat  and  Nagpur. 
There  is  a  considerable 
amount  of  confusion  as  to  the  identity  of  the  various  wheat  and  rice 
borers  reported  in  India  in  the  past,  but  this  species  is  probably  the  most 
important  and  will  be  found  to  be  widespread. 

There  is  no  remedy  for  it  beyond  the  few  commonsense  precautions 

which  are  suggested  by  the  habits 
of  the  pest.  When  first  found  in  a 
wheat  crop,  the  crop  should  be 
periodically  examined,  and  all 
withered  plants  at  once  destroyed. 
The  pest  is  first  found  in  the  most 
advanced  wheat  in  the  districts 
where  it  multiplies,  seriously  injur- 
ing the  later  wheat.  If  the  first 
brood  is  destroyed,  no  appreciable 
harm  will  result.  It  is  unlikely 
that  cultivators  will  ever  find  the 
this   is 


Fig.  141. 
The  Wheat  Stem  Borer  Moth. 
{Slightly  mar/nified.) 


sorghum 
harvest, 
ary,    the 


eggs    and   destroy  them,  though 
quite  feasible. 

The  increase  of  the  pest  is  much 
assisted  in  sorghum-growing  localities 
by  the  practice  of  leaving  the 
stumps  in  the  ground  after 
With  a  few  showers  in  Febru- 
stumps  grow  new  shoots  in 
which  the  caterpillars  of  this  pest  are 
found  after  the  wheat  is  reaped.  This 
helps  the  insect  through  a  very  critical 
period.  W^here  this  insect  attacks  wheat 
on  the  experimental  farm,  spraying  with 
lead  arseniate  must  be  resorted  to  if  the 
full  yield  is  required.  It  thrives  on  the 
plots  of  varieties  of  wheat,  grown  possibly 
with  irrio-ation  under  abnormal  conditions 


Fig.  142. 
The  Wheat  Stem  Borer  Moth. 
{^Magnified  twice.) 


124  pEsts  of  kice  and  wheat. 

and  possibly  not  even  in  a  wheat-growing  area ;  as  in  all  cases  of 
experimental  cultivation  special  remedies  should  be  adopted;  when  this 
pest  is  prevalent,  by  spraying  with  lead  arseniate  to  poison  the  young 
insects  as  they  hatch. 

Minor  Wheat  Pests. 

The  most  important  minor  pest  of  wheat  is  the  aphis  (page  237);  a 
green  aphis  which  infests  the  leaves  and  ears.  It  is  a  fairly  general  pest 
found  in  enormous  abundance  on  ripening  wheat.  It  is  doubtful  how 
much  harm  ajMs  does;  at  its  worst  it  so  weakens  the  plants  and 
grain  that  only  inferior  wheat  is  produced.  Beyond  spraying,  there  is 
no  remedy  possible  until  further  investigation  has  discovered  the  habits  of 
this  pest  throughout  the  year.  Spraying  is  practical  only  on  experimental 
crops  but  is  necessary  there  if  the  full  results  are  to  be  obtained.  Flea 
beetles  (page  203)  attack  wheat,  and  germinating  seed  is  destroyed  by 
ground  grasshojii^ers  and  surface  weevils  (page  220). 

Termites  are  also  a  somewhat  serious  pest  in  some  localities  (page  228). 


V 


CHAPTER  X. 

PESTS  OF  CANE,  MAIZE,  AND  SORGHUM. 

THESE  plants  are  so  closely  related  that  the  same  insects  in  some 
cases  attack  all  of  them.  When  this  is  the  case,  treatment  of  the 
pest  in  one  crop  is  insnfficient,  so  that  it  is  necessary  to  consider  carefnlly 
in  Avhich  crop  and  at  what  time  of  the  year  the  insect  can  be  most  easily 
destro^^ed.  This  is  especially  important  with  the  Moth-borer,  which  is 
the  most  serions  insect  enemy  of  all  three  plants.  Cane  is  also  attacked 
by  the  White-borer,  the  Cane-fly,  the  Cane  Mealy  Wing ;  the  Maize-fly 
attacks  sorghnm  also. 

Moth=borer  in  Sugarcane,  Maize,  and  Sorghum. i 

The    most   abundant    and    serious    pest    to    sugarcane,    maize    and 

sorghum  is  the  cater- 
pillar known  as  the 
moth-borer.  It  is 
found  in  the  cater- 
pillar form,  a  slender 
caterpillar,  not  more 
than     one      inch      in 

Fm.  143.  length,      of     a     dirty 

Motn-lorer.     {Magnified  three  times.)  ^^.^^        ^^^^^^^       ^.^^ 

dark  spots  and  a  black  head.  It  is  not  possible  from  the  caterpillar 
to  be  certain  of  the  identity  of  the  pest,  as  there  are  other  caterpillars 
which  closely  resemble  it  in  form  and  colour.  The  moth  can  be 
identified,  but  it  also  is  similar  to  other  moths  Avith  similar  habits  :  it  is 
advisable,  if  caterpillars  such  as  that  described  below,  are  found  destroying 
these  crops,  to  assume  the  insect  to  be  the  borer,  until  caterpillars  or 
moths  have  been  sent  to  an  entomologist  for  accurate  identification. 
Specimens  are  required  from  all  parts  of  India  to  ascertain  exactly 
where   the  borers  occur    and   whether  one    or    more    species   are  thus 

found. 

Life  Eistory. — The  female  moth  flies  about  the  field  after  dusk  and 
lays  eggs  on  the  leaves  of  the  plants.  The  eggs  are  very  flat,  oval  in 
outline,  about  one  twenty-fifth  of  an  inch  across.  They  are  laid  in  a 
cluster,  one  partly  overlapping  another,  the  number  in  the  cluster  varying 

'       "^  11,     CliiJo  simplex.     Butl.     (Pyralidae.) 


126 


PESTS    OF    CANE,    MAIZE,    AND    SORGHUM. 


from    tlirec    ov   four   to    twenty    or  more.     The    wliole   cluster  forms    a 

. small   patch    on   the    leaf,     usually     about 

a  tliird  of  an  inch  in  length  and 
about  one-twelfth  of  an  inch  across, 
When  first  laid,  the  egg's  are  creamy  white, 
after  which  they  turn  yellow  and  then 
orang'c  before  hatching.  In  about  one 
week  the  caterpillar  comes  out  and  leaves 
the  empty  white  egg-shell.  It  commences 
its  life  as  a  tiny  active  ereatiTre,  about 
one-tenth  of  an  inch  long,  orange  in  colour, 
with  many  short  dark  spines  and  a  black 
head.  It  feeds  upon  the  leaves  of  the  plant 
while  it  is  young,   and  after  a  week  or  so 


Fig.  144. 

Moih-ltorer  l£f)f/s. 
(Mar/nified  fven/i/  times  ) 


enters  the  shoots  or 
the  stem.  If  possible 
it  spends  the  rest  of 
its  caterpillar  life  inside 
the  plant.  The  cater- 
pillar g-rows  larger, 
becoming  a  dirty  white 
colour  ;  the  head  is 
black ;    there    are  many 

little 


Moth-horer. 


Pig.  145. 
{Maffnifed  iliree  times  ) 


Fig.  146. 

Moth-horer  Pwpa. 
[Magnified.) 


dark  spots  on  the  body,  each  of  which 
bears  a  small  dark  hair.  The  usual  three  pairs  of 
legs  and  five  pairs  of  sucker-feet  may  be  seen  with 
which  the  caterpillar  walks  actively  if  disturbed. 
Life  in  this  form  lasts  for  about  four  weeks, 
except  in  the  cold  weather  when  it  may  last  some 
months.  When  the  caterpillar  has  become  full 
grown  and  is  a  little  more  than  one  inch  long,  it 
makes  a  hole  to  the  outside  of  the  plant,  spins  a 
lining  of  thread  inside  the  burroAv  near  this  open- 
ing and  rests  for  two  days.  The  skin  is  then 
thrown  off  and  it  turns  into  a  chrysalis ;  this 
is  three-quarters  of  an  inch  or  less  in  length, 
brown,  with  no  legs  or  mouth.  The  chrysalis 
lies  in  the  burrow,  unable  to  move  except  by 
wriggling,  remaining  thus  for  six  to  seven 
days.  Then  the  skin  splits  open,  and  the  molh 
comes  out. 


MOTH-BOURR. 


127 


Tliis  moth  is  of  a  .2;Toy  brown  colour,  witli  lono'  \oQ;fi,  wiili  two  pairs 
of  wings  and  lias  two  projoctino-  palps  in  front  of  the  head  which  look 
like  a  beak.     The   upper   wino-s  have  dark  marking's,  which    vary   very 


Fia.  14.7. 
Moth.      {^Magni fieri.) 


much  in   different  specimens;   the    lower    wing's    are    white    or    slightly 

grey  :  when  resting,  the   wing-s  are 

carried  close  to  the  body,  the  lower 

ones  not  visible.     When  the  wings 

are    spread,    the     insect    measures 

from   one    to    one   and   a     quarter 

inches  across  ;  the  male  is  smaller 

than  the  female.     It  is  impossible 

to  describe  the    moth  so    exactly 

that  it  can  be  recognised  as  distinct 

from   all     other     moths,    but    one 

point  to  look  for  are  the  palpi  in 

front  of  the  head  which  look  like 

a  beak  ;   if  these  are  not  seen,  the 

moth  is  probably  not  that  of  Ckilo 

simplex,    but     one   of   the     many 

other  moths  found  on   cane,   maize, 

or  sorghum. 

These  moths  mate  and  the  male  dies,  the  female  living  a  day  or  two 
longer  in  order  to  lay  eggs.  In  ordinary  circumstances,  when  there 
is   plenty   of   food   and  the    weather    is    warm,  the  whole    life  history 


Fig.  148. 
Moth  in  repose.     {Magnified.) 


128 


PESTS    OF    CANE,    MAIZE,    AND    SORGHUM. 


Fig.  149. 

Motli-l)orer  Caterpillar,  in  hibernafinij  eondHion. 

{Magnified  three  times.) 


The  withered 
''  deadheart ') . 
killed  in  this 


takes  about  six  weeks,  one  week  for  the  egg-s,  four  weeks  for  the 
caterpillar,  one  week  for  the  chrysalis,  and  a  couple  of  days  for  the  moth 
to  lay  eggs. 

In  November  the  caterpillar  often  ceases  feeding,  and  rests ;  it  does 
not  change  to  the  chrysalis, 
biit  simply  lies  in  its  bur- 
row hibernating.  It  may 
remain  in  this  state  imtil  the 
end  of  May,  when  it  turns 
into  a  chrysalis  and  comes 
out  as  a  moth  in  June.  It 
may  also  come  out  and  rest 
as  a  moth  before  this  time ;  if  there  is  irrigated  cane  or  maize  growing 
during  the  cold  weather  or  dry  weather,  the  moth  may  emerge  as  it  does 
in  the  warm  weather  and  never  hibernate.  This  depends  upon  local 
circumstances,  though  the  rule  is  that  the  caterpillar  hibernates  during 
the  cold  and  dry  weather,  especially  if  it  is  in  sorghum. 

The  caterpillar  is  often  very  destructive  to  young  cane, 
leaves  show  that  the  caterpillar  has  killed  the  shoot 
During  the  first  five  months  many  young  cane  shoots  are 
way,  the  plants  thus  becoming  weak  and  sickly.  When  the  cane  becomes 
larger,  the  caterpillar  attacks  the  stem,  boring  into  the  growing  canes. 
If  it  can  find  other  food,  such  as  maize  or  sorghum,  it  will  often  leave  the 

cane,  but  if  only  cane  is 
grown  it  may  continue  to 
attack  and  damage  the  cane. 
In  sorghum,  the  caterpillar 
attacks  the  young  shoots  just 
as  it  does  in  cane  ;  it  also 
bores  in  the  stems,  being 
usually  very  abundant  as 
the  sorghum  ripens.  Where 
there  are  many  caterpillars  and  each  stem  contains  several,  the  crops  may 
be  seriously  damaged.  After  the  grain  is  harvested,  the  caterpillar 
remains  in  the  dry  stems  and  especially  in  the  stumps,  which  are  left  in 
the  field.  ^ 

In  maize  the  caterpillar  lives  in  all  parts  of  the  plant,  except 
the  roots.  It  bores  in  the  stems,  feeds  upon  the  tassel  and  is 
particularly  fond  of  the  cob.  Many  young  caterpillars  are  often 
found  in  the  ripening  maize,  eating  the  grain  so  that  the  harm  is 
very  apparent, 


Fig.  150. 

Moth-horer  Caterpillar,  in  hihernating  condition. 

{Maffnijled  three  times.) 


MOTH-BORER. 


129 


Remedies. — There  are  several  thing-s  which  may  l)C  done  to  check  the 
increase  of  the  moth-borer,  but  they  will  only  be  fully  efEective  if  they  are 
all  done,  so  that  the  pest  is  checked  all  the  year  round.  No  remedy  will 
entirely  kill  out  the  insect,  and  if  it  is  checked  only  at  one  season  it  will 
increase  again  during  the  rest  of  the  year.  In  every  place  where  the 
moth-borer  is  found,  it  should  be  attacked  in  cane,  maize  and  sorghum,  if 
all  these  are  grown. 

(1)  Cut  out  all  the  young-  shoots  of  cane  that  are  seen  to  wither. 
When  the  moth-borer  attacks  the  shoots,  the  centre  leaves  wither  and 
dry  up ;  if  these  shoots  are  cut  out  with  a  knife,  low  down  just  below  the 
soil,  they  can  be  taken  away  with  the  caterpillar  or  chrysalis  inside. 

This  does  no  harm  to  the  cane  as  the  shoots  would  not  live  in  any  case 
and  other  young  shoots  will  grow  again  just  as  well.  These  dead  shoots 
should  then  be  piled  in  a  heap  and  burnt.  They  must  not  be  left  on  the 
ground  as  the  cater])illar  will  come  out  as  a  moth  in  due  time  and  lay  eggs 
in  the  field  again.  The  object  of  cutting  out  the  cane  is  to  check  the 
borer  at  the  beginning. 

(2)  Sow  maize  or  sorghtmi  among  the  canes  when  the  cane  is  planted. 
This  will  come  up  quickly  and  the  moths  may  lay  eggs  in  the  maize  or 
sorghum  and  the  caterpillars  will  not  attack  the  cane.  The  plants  of  maize 
or  sorghum  may  then  be  removed  with  the  borers  in  them,  say  in  six 
weeks  or  two  months  after  sowing.  These  plants  must  be  removed  from 
the  field  and  if  they  have  many  insects  must  be  destroyed.  In  any  case 
the  insects  must  not  be  allowed  to  come  out  as  moths  and  breed. 

(3)  Cut  out  all  young  sorghum  or  maize  shoots  that  are  attacked  and 
burn  them.  This  is  just  the  same  as  the  first  remedy  and  has  the  same 
effect.  It  can  only  be  done  in  the  young  plants  because  it  is  only  then 
that  the  shoots  which  are  attacked  can  be  seen  by  the  withered  leaves. 
When  the  plants  get  bigger,  the  borer  cannot  be  cut  out,  because  that 
would  kill  the  whole  plant. 

(4)  Destroy  the  stubble  of  the  sorghum  or  maize  plants  after  the 
crop  is  reaped.  During  the  winter  the  caterpillars  live  in  the  stumps  of 
the  sorghum  left  standing  in  the  field.  From  these  caterpillars  come  the 
brood  that  attacks  the  crops  after  the  winter.  Great  numbers  can  be 
destroyed  in  the  stubble  so  that  this  is  the  most  important  remedy  ;  the 
moth-borer  will  probably  be  more  thoroughly  checked  by  this  practice 
than  by  any  other  remedy. 

Enemies.— ks  the  caterpillar  lives  inside  the  plant  few  insects  can 
attack  it,  so  that  many  enemies  that  feed  upon  most  caterpillars  are  power- 
less. Three  insects  are  known  which  lay  eggs  in  the  body  of  the  cater- 
pillars (figs.  151,  322)  ;  these  eggs  hatch  quickly  to  maggots  which  live 


K 


130 


PESTS    OF    CANfE,    MA.I/E,    AND    SOnCHtlM. 


in  the  caterpillar  and  gradually  devour  it.  The  caterpillar  dies,  the 
maggots  come  out  and  themselves  turn  to  flies  which  lay  eggs  in  other 
caterpillars.  Few  of  these  insects  are  found  as  the  caterpillar  is  seldom 
exposed  to  their  attacks. 

A    more    important    enemy    is    a    very    tiny    fly    which    lays   its 

egg  in  the  eggs  of  the  moth ;  the  fly*s 
egg  hatches  first  and  the  maggot  eats  up 
the  eggs  of  the  moth.  Such  eggs  are 
black  in  colour,  not  white  or  yellow,  and 
very  many  such  eggs  are  found  in 
the  fields  of  young  canes.  This  tiny  fly 
is  the  most  important  check  upon  the 
moth-borer  and  prevents  the  destruction 
of  many  cane-fields  every  year.  Another 
enemy,  which  is  very  seldom  found,  only 
attacks  the  borer  when  it  is  feeding  upon 
some  exposed  part  of  the  plant,  such  as 
the  tassel  of  maize.  This  is  a  very 
active  small  black  grub,  which  runs  about 
feeding  upon  the  caterpillars.  It  kills  the  caterpillars  by  sucking  out 
their  blood. 

The  moth-borer  is  found  in  many  parts  of  India,  but  it  is  not  certain 
that  it  occurs  all  over  the  continent.  It  is  common  in  many  places  in 
the  Bombay  Presidency,  Baroda,  the  Central  Provinces^  Bengal,  the 
Punjab  and  the  United  Provinces.  It  will  probably  be  found  all  over 
these  Provinces  and  is  likely  to  be  the  borer  of  cholam  (sorghum) 
in  Madras. 


Fig.  151. 

Fit/  whose  Maggot  lives  in  the 

Moth-horer  Caterpillar. 

{Magnified  twice.) 


White  Borer  of  Cane.^ 

Whilst  the  moth-borer  is  the  common  pest  of  cane,  other  boring 
caterpillars  also  attack  it,  some  in  the  roots,  others  in  the  stalk.  Of 
these  the  "White  Borer  is  the  most  prominent,  found  principally  at  the 
apex  of  cane,  boring  through  the  growing  joint  and  down  the  upper 
joint. 

The  moth  lays  eggs  on  the  leaves  of  the  cane,  several  eggs  together 
in  a  cluster ;  the  eggs  are  cigar-shaped,  fixed  to  the  leaf,  and  the  ^cluster 
is  covered  with  buff  coloured  hair  taken  from  the  tip  of  the  moth's 
abdomen.  When  the  moth  deposits  eggs  covered  with  a  gummy 
secretion,  the  hairs  from  the  end  of  the  body  are  plastered  over  the  eggs. 

*  \%\.  Scirpophaga  auriflua.    Zell.     (Pyralid^ ) 


WUITK    I'.ORKlt. 


131 


The  cg'g-  cluster  thus  lias  a  very  characteristic  appearance  and  can  be 
readily  found. 


Fig.  152. 

White  Borer.     Larva,  Male  and  Female  Pupa.     Papa  in  the  cane. 

Moth,  male  above. 

The  larvae  that  hatch  are  small  spiny  insects  not  unlike  the  moth- 
borer.  They  behave  in  much  the  same  way,  eating-  down  into  the 
rolled-up  leaves  of  the  cane  shoot.  They  pierce  the  rolled-up  leaves,  which 
have  a  characteristic  appearance  when  they  open,  the  leaves  being- 
spotted  with  small  holes.  Eventually  they  bore  into  the  growing  point 
and  straight  down  the  solid  part  of  the  shoot. 

In  old  canes  the  larva  eats  down  the  centre  of  the  young  rolled- 
up  leaves  above  the  growing  point  till  it  reaches  the  latter.  The  grow- 
ing point  is  destroyed  and  the  larva  continues  eating  through  the  soft 
tissue,  travelling  downwards.  When  it  becomes  fully  fed,  it  bores  to 
the  outside,  reaching  first  the  rind  of  the  cane,  then  perforating  the 
sheathing  leaves.  The  leaf  on  the  outside  is  not  eaten  away  but  a  neat 
round  disc  is  cut  and  left  blocking  the  tunnel.  The  tunnel  is  then  webbed 
with  silk,  and  if  there  is  a  space  between  the  rind  of  the  cane  and  the 
outer  leaf,  this  is  bridged  by  a  silken  tube. 

The  pupa  retires  into  the  tunnel  and  prepares  cross  partitions  as  it 
goes,  webbing  the  tunnel  across  with  partitions.  It  then  settles  down, 
the  skin  is  cast  and  pushed  behind  it,  and  the  pupa  lies  head  downwards 
in  the  tunnel, 


132  PESTS    OF    CANE;,    MAIZE,    AND    SOBGHUM. 

The  caterpillar  bores  through  several  internodes  of  the  cane  before 
turning'  outwards  ;  as  a  rule  there  are  at  least  three  internodes  between 
the  apex  and  point  of  emergence. 

In  old  canes,  the  death  of  the  growing  point  by  this  caterpillar  leads 
to  the  development  of  the  buds  next  to  the  apex  and  some  distance  down 
the  cane.  The  result  is  a  cane  bearing  large  shoots  on  the  upper  half, 
forming  a  bunchy  top  of  long  green  shoots.  Such  canes  are  very  con- 
spicuous ;  the  yield  must  be  largely  reduced,  the  cane  instead  of  ripening 
normally,  having  to  form  shoots  at  the  expense  of  its  sugar  contents.  The 
upper  half  of  the  cane  is  also  more  fit  for  feeding  cattle  than  for  grinding. 
In  young  canes,  the  effect  of  the  attack  is  to  produce  a  "  deadheart/^ 
a  single  dead  shoot  which  grows  no  more. 

Before  the  cold  weather  becomes  severe,  the  larvse  that  are  full  fed 
turn  to  chrysalides  and  remain  thus  throughout  the  winter.  At  Pusa, 
the  first  moth  was  caught  in  the  fields  in  1905  on  March  9th,  probably 
an  abnormally  late  date.  Many  chrysalides  could  be  found  at  that  date, 
though  they  hatched  out  soon  after.  Probably  the  end  of  hibernation 
is  a  fairly  distinct  period,  most  moths  hatching  out  about  the  same  time. 
The  commencement  of  hibernation  cannot  be  fixed  so  clearly.  Moths 
were  common  up  to  the  end  of  October  and  in  early  November.  After 
that  none  were  caught  and  probably  the  last  had  emerged  in  November. 
AH  pupse  would  then  probably  hibernate  by  the  end  of  November, 
full  fed  larvae  would  turn  to  chrysahdes  and  smaller  larvse  would 
feed  till  the  cold  numbed  them,  or  till  they  could  in  turn  become 
chrysalides. 

The  wings,  legs,  body,  head,  etc.,  of  the  moth  are  clothed  in  white 
scales,  the  only  colour  visible  being  at  the  end  of  the  abdomen.  In  the 
female  the  abdomen  terminates  in  a  dense  tuft  of  brown  hair,  the  outer 
layer  of  which  is  red  in  the  variety  intacta.  The  amount  of  this  hair  is 
extraordinary,  and  as  stated  above  is  used  for  covering  the  eggs.  The 
females  are  larger  than  the  males  and  may  be  known  by  this  tuft  of 
hair.  Both  sexes  can  be  easily  found  in  the  field,  sitting  on  leaves  of 
cane  or  other  plants  during  the  day-time,  flying  actively  when  the  sun 
goes  down. 

As  a  rule  mating  takes  place  on  the  first  night  and  egg-laying  may 
occur  on  the  second  but  may  be  delayed.  Moths  do  not  all  emerge  with 
the  eggs  fully  developed ;  dissection  of  reared  moths  shows  that  in  some 
the  eggs  are  not  so  fully  developed  as  in  the  majority  and  such  moths 
probably  live  a  day  or  two  longer. 

The  number  of  eggs  actually  laid  by  moths  cannot  be  accurately 
ascertained^  even  under  the  best  conditions  in  captivity  moths  do  not 


teliave  normally ;  they  may  lay  unfertilised  eggs,  they  may  lay  no  eggs, 
or  few,  or  the  full  number  contained  in  the  ovary  may  be  deposited 
irregularly.  In  natural  conditions  the  eggs  are  laid  a  few  at  a  time 
scattered  over  some  area,  each  egg  cluster  being  carefully  finished 
off.  In  captivity  this  is  not  possible.  Dissection  of  mature  females  shows 
that  there  are  about  one  hundred  eggs  in  the  ovaries  which  appear  to  be 
uniform  in  size  and  fit  for  deposition ;  immature  females  will  contain  from 
sixty  to  seventy  large  eggs  and  others  in  various  stages  of  develop- 
ment; probably  one  hundred  is  approximately  the  number  of  perfect 
developed  eggs,  and  in  normal  circumstances  the  majority  of  these  are 
probably  laid. 

The  males  die  after  coupling,  the  females  after  egg  laying ;  the 
moths  that  can  be  caught  in  the  fields  are  freshly  emerged  males  or 
females  that  have  not  laid  eggs. 

The  eggs  are  attacked  by  parasites,  as  are  also  the  larvae. 

There  are  three  methods  of  checking  the  pest : — • 

(1)  The  eggs  can  be  collected  on  the  young  plants  especially  when 
the  first  moths  come  out  at  the  first  warm  weather.  These  eggs  should 
not  be  destroyed  but  be  put  in  a  tray  or  dish  standing  in  a  larger  dish 
of  water  or  into  a  tray  with  a  gutter  of  water  round  the  rim.  The  para- 
sites hatch  out  and  fly  away,  the  caterpillars  that  hatch  being  unable  to 
cross  the  water  and  dying.  In  this  way  the  parasite  is  not  destroyed, 
but  continues  to  do  its  good  work  in  the  canes. 

(2)  The  young  shoots  can  be  cut  out  when  they  are  seen  to  wither, 
and  the  insect  destroyed  with  the  shoot.  This  is  exactly  similar  to  the 
remedy  for  moth-borer. 

(3)  The  bunchy  tops  of  the  canes  which  are  attacked  can  be  cut 
out  and  used  as  fodder.  The  last  is  probably  necessary  only  in  bad 
attacks. 

The  pest  has  been  fomid  commonly  in  Behar  and  in  parts  of  the  United 
Provinces.  It  is  also  known  in  Java.  The  moth  has  a  wider  distribu- 
tion in  India  and  will  probably  be  found  in  sugarcane  throughout 
the  plains. 

The  Sugarcane  Fly.i 

A  dull  straw-coloured  insect,  about  half  an  inch  in  length,  with  a 
conspicuous  upturned  proboscis,  which  is  found  abundantly  in  the  canes ; 
it  leaps  and  flies  with  great  agility  ;  the  female  is  conspicuous  by  a  mass 
of  white  material  at  the  end  of  the  body.     This  fly  is  not  difficult   to 

»  147.     Bictyophara  pallida.     Don.     (Fulgoridse.) 


134  PESTS    OF    CANE,    MAIZE,    AND    SORGHUM. 

recognise,  being   found  in    great  numbers  in    fields  of   old    cane.     Tlie 


Fig.  153. 

The  Cane-fy,  showing  Eggs,  Nymphs  and  Imago.     Tlie  nymphs  are  denuded  of 

their  mealy  covering  and  processes. 

{Magnified  Jive  limes.) 

female  lays  eggs  on  the  lower  surface  of  the  cane  leaf,  near  or  on 
the  mid  rib ;  the  eggs  are  oval,  about  one- twenty-fifth  of  an  inch 
in  length,  pale  green  or  yelloAV  in  colour.  They  are  deposited  in  a 
loose  irregular  mass  covered  with  white  cottony  material  forming  a 
conspicuous  object  on  the  leaf.  From  ten  to  thirty  eggs  are  found 
in  each  mass.  They  hatch  after  a  few  days,  and  active  young  bugs 
emerge  Avhich  are  able  to  suck  the  juice  of  the  plant.  These  insects 
have  at  the  hind  end  a  pair  of  long  straight  processes,  covered  in 
white  mealy  wax,  which  they  can  move  apart  or  bring  close  together. 
They  hop  vigorously  from  leaf  to  leaf  and  rapidly  grow  larger.  The 
Avings  appear  as  lobes  on  the  back,  and  after  five  moults  the  perfect 
Avinged  insect  appears. 

This  insect  is  found  only  in  cane,  and  is  apparently  widely  spread 
over  the  Punjab,  United  Provinces  and  l?ehar,  l)ut  has  not  been  found  in 
Western  India.  Its  origin  is  obscure,  and  though  it  becomes  abundant 
in  cano,  it  has  not  been  found  ui)on  wihl  plants  and,  unless  brought 
from  cane  fields,  does  not  come  out  of  the  jungle  and  infest  new  cane 
lands.  In  old  cane  fields  it  is  common,  but  the  damage  is  appreciable 
only  in  the  rare  cases  when  it  is  very  abundant. 


CANE    MEALY    WlKG. 


l35 


The  insect  sucks  out  the  juice  of  the  leaves  and  canc^  thus  weakening 
the  plant ;  the  principal  effect  of  its  presence  in  large  numbers  is  that 
the  juice  of  such  canes  makes  bad  sugar. 

The  pest  can  be  checked  only  by  collecting  the  eggs  regularly  and 
systematically  till  the  numbers  of  the  insect  are  reduced.  This  is  easier 
on  young  canes  but  usually  necessary  on  maturing  canes. 

No  other  method  is  so  simple  and  the  use  of  insecticides  for  this  pest 
is  impossible. 


Cane  Mealy  Wing.^ 

A  disease  of  cane  well  known  to  cultivators,  takes  the  form  of 
small,  oval,  scale-like  bodies  attached  firmly  to  the  leaf ;  each  is  black 
in  the  centre,  with  a  white  fringe,  about  one-twentieth  of  an  inch  long, 
never  moving  about  on  the  leaf.  This  is  the  immature  form  of  the  Cane 
MeaJy  "Wing;  it  cannot  be  mistaken  and  is  usually  found  in  large 
numbers. 

bodies   are    the     developing    insects,     correspond- 


me* 


These  scale-like 
i-  to  the  half 
grown  larvae  and 
pupae  of  a  moth. 
If  the  life  history 
is  traced  from  the 
beginning  we  find 
0  r  a  n  o-  e-c  o  1  o  ured 
eggs,  very  small, 
laid  singly  on  the 
leaf  a  number  close 
together.  The  larvae 
that  hatch  are  small 
flattened  insects, 
having  tiny  legs 
and  antennae,  which 
walk  a  short  dis- 
tance on  the  leaf, 
fine    beak   into    the 


Fig.  154 

Effffs  and  Scales  of  the  Cane  Mealy  Wing. 

{Magnified  ttvehe  times.) 


As  each  finds  a  suitable  place  it  inserts  its 
caf  and  fixes  itself  down.  At  the  first  moult 
it  assumes  the  scale-like  form  and  remains  motionless;  its  food  is 
obtained  by  suction  from  the  leaf  and  the  insect  has  no  further  need  of 
legs  or  antennae. 

'  Ccc.  39.     Aleurodes  harodensis.     Mask.     (Aleurodidec.) 


l36  PESTS  OF  CanE;  Maize,  and  soRGUUivi. 

Within  this  scale  it  completes  its  larval  life,  transforms  to  the  pupa, 
and  finally  emerges  as  a  tiny  moth-like  flying  insect ;  there  are  now  two 
pairs  of  Avings,  and  both  sexes  are  to  be  found.  These  mate,  eggs  are 
laid  and  the  life  history  recommences. 

This  pest  is  common  on  cane  in  widely  separated  parts  of  India. 
Like  other  sucking  insects,  it  is  more  numerous  on  weak  cane,  proving  a 
serious  pest  if  it  once  becomes  abundant.  The  plant  steadily  loses  vigour 
as  the  result  of  the  constant  drain  of  sap,  and  unless  it  is  growing  freely 
becomes  stunted  and  yellow. 

Parasites  attack  the  scales  and  it  is  not  uncommon  to  find  a  large 
percentage  destroyed.  The  pest  cannot  be  treated  once  it  becomes  well 
established,  and  everything  possible  should  be  done  to  prevent  infection  of 
the  young  canes,  either  from  the  plant  canes  used  or  from  neighbouring 
fields  of  uncut  canes. 

If  the  pest  appears  on  young  canes,  the  infested  leaves  should  be 
removed.  Poor  canes  that  are  not  growing  vigorously  are  sure  to  suffer 
from  such  pests  ;  a  vigorous  healthy  cane  may  become  infested  but  suffers 
little  from  the  insect.  In  most  cases  the  insect  is  a  sign  of  a  poor  cane, 
just  as  lice  and  ticks  are  of  an  unhealthy  bullock,  and  the  radical  course 
is  to  grow  a  better  cane  or  manure  it  more  highly. 

The  cultivators  of  Gujarat  regard  this  disease  {mosi)  as  a  very  serious 
one  and  state  that  it  decreases  the  yield  from  100  maunds  to  30  and  renders 
the  cane  unfit  for  seed.  They  adopt  no  remedy  but  withhold  irrigation  in 
the  belief  that  if  the  plant's  growth  is  checked  that  of  the  pest  will  be  checked 
also.  This  is  probably  erroneous.  They  also  state  that  mist  and  damp  kill 
the  pest.  The  Behar  cultivator  has  a  similar  belief  in  the  destructiveness 
of  the  pest  [lahi)  but  appears  to  adopt  no  remedy  against  it. 

Minor  Pests  of  Sugarcane. 

The  Rice  Grasshopper  (page  119)  is  reported  as  attacking  sugarcane 
but  is  not  generally  a  pest  of  this  crop.  The  Rice  Leptispa  (page  201)  is 
also  reported  as  feeding  on  sugarcane  leaves,  and  the  Sugarcane  Hispa  is 
actually  found  on  cane  but  does  no  harm. 

Termites  or  white-ants  are  serious  enemies  especially  to  young  cane. 

Three  borers  have  been  found  by  Mr.  M.  Mackenzie  in  Bel\ar,  and 
these  are  as  yet  little  known.  The  larva  of  the  Gold-fringed  Moth  i  attacks 
cane  much  as  the  moth-borer  does  j  the  Green  Borer  ^  attacks  the  portion 
of  the  cane  below  the  soil,  and  a  third  borer  ^  is  found  in  the  stalk. 

1  122.  Chilo  auricilia.   Ddgn.  (Pyralidte.)  |  '  146.  Anerastia  ahlidella.   Zell.  (Pyralidse.) 
'*  149.  Polyocha  saccharella.  Ddgn.  (Pyralidse.) 


MAIZE   tLY. 


is? 


Ground  weevils  of  three  species  attack  the  young  canes  and  are  best 
cliccked  by  sowing"  maize  or  sorg-hum  with  the  canes,  to  supply  them  with 
other  food.  Leaf-eating  caterpillars  eat  the  leaves  of  cane  but  are  not  of 
any  importance.  Three  mealy  bugs  (page  245)  are  found  on  cane  and 
may  do  a  small  amount  of  damage  in  the  aggregate  but  are  checked  by 
sowing  only  clean  seed  canes. 


The  Maize  Fly.i 

A  small  dark-coloured  insect,   not   unlike  a   large    aphis,    is   found 
in  the  sheathing  leaves  of  maize  and  sorg-hum.     The  insects  are  active 
running   crab  like    with    a   sideways    motion   and   leaping   away    when 
disturbed. 

Eggs  are  laid  in  the  tissues  of  the  plant,  a  cut  being  made  in 
the  leaf  and  the  eggs  deposited  in  the  cut  with  a  coating  of  white 
secretion. 

The  young  are  active,  grey  brown  in  colour,  running  in  the  heart  of 

the  j)lant.  Large  colo- 
nies of  all  ages  are  found 
in  infested  plants.  Tlaey 
feed  by  extracting  the 
juice  from  the  tissues  of 
the  plant.  Young  sor- 
ghum plants  are  affected 
as  well  as  maize.  The 
insect  is  not  a  pest  to 
field  cultivation  of 
maize  in  large  areas, 
but  to  plots  of  maize 
grown  where  the  crop  is 
not  a  staple.  It  weakens 
exotic  and  unhealthy 
plants,  and  is  one  of  the 
minor  pests  so  common  in  experimental  cultivation.  It  is  allied  to  the 
cane-fly  of  the  West  Indies,  an  insect  with  similar  habits  which  attacks 
sugarcane. 

Numbers  of  these  insects  are  found  in  grass  lands,  being  one  of  a 
large  group  of  common  sucking  insects  which  are  generally  restricted  to 
their  wild  food-plants.  As  a  rule  no  remedy  is  needed  beyond  the  simple 
one  of  dropping  ashes  or  lime  and  kerosene  into  the  heart  of  the  plant  to 

'  4.     Belphax  psylloides.     Leth.     (Fulgoridae.) 


Fia.  155. 
Maize  Fly.      n,  Imago.      b,  c,  d,  Young.      e,  Egg. 
Antenna,     g,  h,  k,  Legs.     (All  magnijied.) 


f. 


Ids 


PESTS    OF    CANE,    MaIZE^    AND    SORGHUM, 


drive  out  the  flies.  In  bad  cases  spraying"  is  required,  the  ordinary 
contact  poisons  being  sufficient  to  check  the  pest  on  a  valuable  plot  of 
maize  or  sorghum. 

Minor  Pests  of  Maize. 

Maize  is  the  food-plant  of  a  great  number  of  insects  which  rarely  do 
it  serious  injury ;  only  where  it  is  grown  in  small  quantities  and  is  not 
the  staple  crop  do  these  pests  become  so  numerous  on  each  plant  as  to  do 
much  damage.  Moth-borer  is  not  uncommon  in  maize  and  may  do  much 
harm.  The  Hairy  Caterpillar  of  Gujarat  (page  193)  will  eat  maize  if  it  has 
no  other  food.  Swarming  Caterpillars  destroy  maize  as  they  do  other  crops 
but  are  not  specially  addicted  to  this  crop  (page  187).  The  Maize  Leaf 
Caterpillar^  does  an  inappreciable  amount  of  harm  in  ordinary  seasons 
by  feeding  on  the  leaves.  Many  other  caterpillars  attack  maize,  eating 
the  young  plants,  feeding  on  the  tassel  or  destroying  the  cob.  None  are 
specific  pests ;  one  particular  pest  of  small  irrigation  crops  in  April  and 
May  ^  is  fond  of  maize  as  also  is  the  Gram  Caterpillar  (pages  144-45). 
The  White  Weevil  (page  202)  eats  maize  leaves  and  the  two  smaller 
Blister  Beetles  (page  205)  have  been  reported  as  destroying  the  flowers 
of  this  plant. 

Minor  Pests  of  Sorghum. 

This  crop  has  few  pests ;  the  two  smaller  Blister  Beetles  (page  205) 

are    quite    serious    pests,    destroying    the 

flowers     and     lessening     the     yield.      The 

Wheat  Stem-borer  (page  122)  also  attacks 

it,  and  a  leaf-eating  caterpillar  ^  is  common 

in  the  young  shoots  but  destructive  only 

when  in  great  numbers  on  a  small  area  of 

the  crop.     This  caterpillar  does  occasionally 

come   in   great   numbers,    feeding   on    the 

plant  by  night,  lying  hidden  in  the  soil  by 

day.     When   this   is   the   case,   iDloughing 

or  cultivation  is  advisable  if  it  be  possible. 

Fig.  156.  The    eateri^illars    can    be    trapped     under 

Sorghum  Leaf  Caterpillar.         heaps  of  fodder  laid  on  the  soil,  as  they 

will  gather  there  by  day  and  can  be  readily  destroyed.     The  moth-borer 

is  the  serious  pest  of  sorghum  though  only  rarely  becoming  destructive. 

The  bugs  that  suck  the  heads  of  this  plant  in  South  India  are  stated  to 

'  210.     Marasmia  trapezalis.     Guen.     (Pyralidae.) 
'  llO.     Caradrina  exiffita.     Hubu.     (Noctuidte.) 
'     29.     Cirphis  unipu'ncta.     Haw,     (Noctuidse.) 


SOllGIIUM    fESTS. 


l39 


be  serious  pests^  mucli  feared  by  cultivators.  Other  widespread  pests 
in  Madras  are  described  by  Mr.  Barber.'  Of  these  tlie  mite  which 
produces  an  appearance  similar  to  rust  is  a  widespread  pest  in  some  years. 
On  the  whole  this  crop  appears  to  be  fairly  free  from  pests  and,  when 
g-rown  in  large  areas,  the  pests  are  often  so  widely  spread  that  little 
injury  results. 

'  Bulletiu  Nl).  49.     Diseases  of  Audropogou  sorghum  iu  Madras.     (1904.) 


Chapter  xl. 


PESTS  OF  LEGUMINOUS  CROPS. 

BESIDES  the  four  pests  described  below,  few  insects  are  known  to 
attack  leguminous  plants.  This  is  largely  due  to  the  fact  that  these 
plants  are  mainly  subsidiary  crops,  so 
that  destructive  insects  have  not  the 
same  opportunities  for  attack.  The 
pests  described  probably  have  a  greater 
range  among  the  leguminous  crops 
than  is  at  present  known ;  the  pod 
caterpillar  of  tur  is  found  on  val 
[Dolic/ios  lab-lab)  and  probably  on 
other  pulses. 

Tur  Pod  Caterpillar. 

As  the  tier  or  ar/iar  {Cajanus  indi- 
cus)  crop  ripens,  the  seeds  are  des- 
troyed by  small  caterpillars.  These 
are  the  larvae  of  the  Tur  Plume 
Moth  (fig.  160),^  an  insect  first  found 
in  Nagpur  and  since  recognised  in 
several  parts  of  India. 

Life  Bistory. — The  life  history  resembles  that  of  other  moths.     Small 

round  eggs  are  laid 
singly  by  the  moth 
on  the  flower  or 
small  pods.  These 
hatch  in  five  days 
to  small  greenish 
caterpillars,  which 
eat  through  the  pod 
and  feed  upon  the 
seeds  within.  The 
caterpillar  dges  not 
enter  the  pod  but 
Pjg    253  makes  a  hole  to  the 

Tii'^a  of  Tur  Flume  Moth.     {Magnifud  six  times.)  seed,  and  feeds  from 


Fig.  157. 

Tur  Pod  Caterpillar  on  left,  a  bunch  of 

spines  as  found  on  each  segment 

on  right. 


*  72.  Exelasta  parasita.    Meyr.    (Pterophoridse.) 


TUR    PESTS. 


141 


outside.  Having'  eaten  one  seed  it  makes  a  hole  opposite  anotlier  and  attacks 
that.  The  L^^rva  is  green  or  brown  or  a  mixture  of  both.  The  colour  is 
similar  to  that  of  the  pod,  that  singular  mixture  of  green  and  brown,  and 
so  is  not  easily  seen.  The  body  is  dotted  with  dense  tufts  of  spines  and 
hairs,  the  former  of  peculiar  form,  either  single  or 
radiating  from  points  in  each  segment  (fig.  157). 

After  a  larval  life  of  25  to  30  days,  the  chry- 
salis is  found  on  the  pod.  It  is  coloured  exactly  like 
the  pod  and  is  clothed  in  fine  hairs  as  is  the  larva. 
After  seven  days,  the  moth  emerges,  a  singularly 
graceful  moth,  with  long  narrow  wings.  It  may  be 
found  flying  in  the  dusk  and  comes  readily  to 
lights  (fig.  160). 

JDescription. — The  pest  is  a  common  one  on  tur 
or  arhar  [Cajamis  indicns)  and  is  found  commonly 
in  Bombay,  Central  Provinces  and  Beliar.  It  has 
not  been  reported  from  many  districts,  but  is  an 
inconspicuous  insect,  and  is  probably  common 
throughout  the  plains.     Where  this  crop  is  grown  ^ i<^- 159. 

extensively,  the   pest  does   no    appreciable   harm.        "^"^'"^  "-^^^^  ^^"'"' 
Where  small  areas  of  tur  are  grown,  it  may  be  very      {Magnified  six  times.) 


Fig.  160. 
fur  Plume  Moth.     {Magnified  five  times.) 


14&  PESTS   OF    LEGUMINOUS   CROPS. 

destructive,  causing  a  loss  of  quite  forty  per  cent.     In  addition  to  tur  it 
has  been  found  on  val  {Doliehos  lab-lab)  and  probably  attacks  other  pulses. 

Remedies. — No  case  has  been  seen  where  remedies  for  it  -were  required 
except  in  experimental  plots.  On  such  plots,  spraying  with  strong  contact 
poisons  is  a  simple  and  radical  cure.  A  sprayed  plot  gave  an  increased 
yield  of  fifty  per  cent,  over  a  similar  unsprayed  plot.  Serious  attacks  of 
this  pest  in  large  areas  could  be  cheeked  by  hand-picking  or  other  tedious 
methods,  and  where  such  attacks  occur  preventive  measures  should  be 
taken  in  the  following  seasons.  The  only  really  valuable  preventive 
measure  probably  lies  in  not  growing  any  leguminous  crop,  such  as  val, 
mung  {P/iaseohis  mungo),  etc.,  from  the  time  the  tur  is  picked  till  the 
next  crop  is  ready.  By  this  means  the  pest  will  be  starved  out  and  will 
not  be  abundant  in  the  next  season.  This  is  a  matter  of  local  conditions, 
tur  ripening  so  much  sooner  in  some  parts  of  India  than  in  others.  The 
pest  has  alternative  food-plants  in  the  small  mass  of  leguminous  crops 
grown  in  the  hot  weather  and  rains,  chiefly  vegetable  crops  which  form 
pods  at  a  time  when  the  pest  has  not  got  its  staple  food. 

Tur  Pod  Fly.i 

A  small  white  maggot,  found  feeding'  upon  the  seeds  of  tur ;  the 
injury  is  apparent  only  when  the  insect  leaves  the  pod,  there  being  at 
first  no  sign  of  the  attack.  A  small  hole  in  the  pod  is  the  only  external 
sio-n  of  an  infested  pod.  This  pest  was  discovered  in  the  Central 
Provinces  ^  and  has  since  been  found  in  Behar.  The  fly  lays  an  c^g  in  the 
pod  piercing  the  shell  with  her  ovipositor  and  leaving  a  single  egg  behind. 
The  maggot  feeds  upon  the  tur  seed,  first  tunnelling  under  the  skin,  later 
devouring  a  large  part  of  it.  Only  one  seed  is  eaten  and  several  maggots 
may  inhabit  the  same  pod.  The  maggot  is  a  typical  fly  maggot,  small, 
white,  without  legs  or  head,  the  mouth  at  the  tapering  end  with  small 
black  hooks ;  in  length  it  is  one-eighth  of  an  inch.  AVhen  full  grown 
it  eats  almost  through  to  the  outside,  leaving  only  the  thin  outer  skin  of 
the  seed  intact.  It  transforms  within  to  the  brown  seed-like  pupa,  and 
when  the  fly  emerges,  it  pushes  through  the  thin  skin  left  by  the  larva 
and  emerges  directly  into  the  air.  Larvae  and  pupse  are  found  in  the  same 
pod.  The  fly  is  a  very  small  black  insect,  the  wings  large  in  comjparison 
to  the  body.  It  is  common  in  the  tur  fields,  though  not  easy  to  find  or 
to  recognise  from  other  small  black  flies.  The  female  has  an  ovipositor, 
an  organ  resembling  the  sting  of  a  wasp. 

'  194.     (MiiBcidse  acalyptratae.) 

'  Bv  Bntiram  Khampftria,  Entomological  Assistant. 


TUR    PESTS.  143 

The  lifo  history  appears  to  be  a  short  one  and  broods  probably 
succeed  one  another  rapidly.  The  increase  of  the  insect  is  chccke'l  by 
hymenopterous  parasites. 

No  precautions  are  possible  once  the  fly  has  laid  eggs  in  the  pods. 
Nothing-  can  then  be  done  to  destroy  the  insect  without  destroying-  the 
pods  also.  It  is  unlikely  that  the  insect  causes  serious  harm  in  large  areas 
of  tur.  Much  has  to  be  learnt  of  this  insect  before  preventive  measures 
can  be  devised. 

Tur  Leaf  Caterpillar.^ 

This  caterpillar  feeds  upon  the  small  upper  leaves  of  the  tur  plant, 
webbing-  them  together  into  a  small  compact  mass  within  which  it  lives. 
The  webbed  leaves  are  very  conspicuous  so  that  the  pest  is  at  once 
recognisable. 

The  moth  lays  eggs  on  the  upper  leaves,  the  eggs  being  laid  sing-ly, 
scattered  over  many  plants.  A  small  white  caterpillar  hatches,  which 
feeds  upon  the  leaf.  It  draws  together  the  very  small  leaves  at  the  tip 
of  the  shoot  in  the  usual  way  characteristic  of  caterpillars ;  commencing 
with  two  leaves  close  together,  it  rapidly  draws  a  thread  between  them, 
the  thread  being  of  soft  gummy  matter,  exuded  from  the  lower  lip  of  the 
insect ;  first  touching  one  leaf  with  the  end  of  the  lower  lip  it  affixes  the 
gummy  matter,  draws  it  rapidly  across  to  the  other  leaf  and  so  produces 
the  first  thread ;  it  then  returns,  bringing  a  second  thread  to  the  first 
leaf  and  continues  to  move  from  one  to  another,  producing  small  threads 
which  rapidly  dry  and  so  contract ;  as  the  first  threads  dry  they  pull  the 
two  leaves  together  and  the  later  threads  are  shorter ;  all  the  threads  as 
they  dry  shorten  and  their  united  pull  eventually  brings  the  two  leaves 
together ;  the  caterpillar  then  commences  on  a  new  leaf,  and  draws  that 
close  to  the  two  previously  webbed  ones,  so  continuing-  till  it  has  prepared 
its  habitation.  Within  this  knot  of  leaves  the  caterpillar  lives  ;  it  orows  to 
a  length  of  one  quarter  of  an  inch,  smooth,  with  no  markings,  the  head 
brown,  a  very  small  prothoracie  shield  and  the  body  a  yellow  tendino-  to 
orange.  When  full  fed  it  pupates  within  the  twisted  leaves  and  a  tiny 
dark-coloured  moth  emerges.  This  moth  is  never  seen  in  the  fields 
being  very  small  and  coming  out  only  at  night  or  in  the  dusk. 

This  pest  attacks  the  young  tur  plants  in  July,  August  and  Septem- 
ber. It  produces  a  very  characteristic  form  of  injury,  which  is  of  little 
importance  unless  the  top  shoot  is  so  drawn  into  the  knot  that  it  is  killed. 
When  only  side  leaves  are  drawn  in,  the  leaves  alone  are  killed,  but  where 
the   top   shoot   is   affected,   it   is   bitten   throug-h     and  side   shoots  are 


143.     Hucelis   critica.     Meyr.     (Tineidse,) 


144 


PESTS    OF    LEGUMINOUS    CROPS. 


thrown  out  producing  a  somewhat  stunted  bushy  plant.  In  all  the  cases 
observed  a  very  large  percentage  of  the  larvae  are  killed  by  parasites, 
which  puts  a  great  check  on  the  pest.  The  small  white  cocoons  of  the 
parasite  are  found  in  the  twisted  leaves  of  the  caterpillai-'s  dwelling  and 
may  be  mistaken  for  some  stage  of  the  pest's  life.  The  pupa  of  the  pest 
is  the  usual  small  brown  pupa  lying  naked  in  the  leaves. 

The  pest  has  been  found  in  several  widely  scattered  districts  in  the 
plains.  It  is  most  abundant  in  plots  of  unmixed  tur,  less  so  where  tur  is 
sown  with  maize,  til  or  other  crops.  These  crops  coming  up  more 
rapidly  than  the  tur,  serve  to  hide  it  to  some  extent,  and  though  mixed 
crops  are  attacked,  unmixed  tur  suffers  more.  Possibly  this  has  some 
connection  also  with  the  habits  of  the  parasite  which  may  prefer  the  tur 
grown  under  shelter  of  another  plant  to  tur  grown  in  the  open,  and  so 
destroy  the  insect  more  largely. 

The  very  simple  remedy  of  pulling  off  the  affected  leaves  is  suffi- 
cient to  check  it.  These  knots  of  leaves  are  readily  seen  and  can  be  rapidly 
and  easily  collected  by  hand.  The  caterpillars  collected  should  not  be 
destroyed  but  placed  in  a  box  or  some  closed  receptacle  ; 
the  parasites  will  hatch  out  gradually,  and  if  the  box  be 
cautiously  opened  in  the  day-time  in  bright  light,  they 
will  fly  out ;  the  moths  will  not  escape  at  the  same 
time  if  the  box  is  carefully  opened.  In  this  way,  the 
valuable  parasitic  flies  will  not  be  destroyed,  but  will 
return  to  the  fields  to  complete  their  useful  work. 


The  Gram  Caterpillar. 

The  seeds  of  the  gram  plant  are  commonly  eaten 
by  a  large  green  caterpillar,  somewhat  over  one  inch 
long  when  full  grown,  which  sits  on  the  outside  of  the 
pod.  This  is  a  cosmopolitan  pest  ^  which  attacks  an 
enormous  variety  of  crops  all  over  the  world. 

The  life  history  is  identical  with  that  of  similar 
caterpillars  ;  the  eggs  are  laid  singly  on  the  food-plants, 
small  whitish  eggs,  round  and  beautifully  sculptured  ; 
the  caterpillars  feed  for  a  short  time  on  the  leaf  or 
the  outside  of  the  gram  pod  and  then  bite  through  to 
the  seeds ;  they  feed  from  outside,  attacking  one  seed 
after  another,  but  not  bodily  entering  the  pod  and 
remaining  there.     This  period  lasts  about  a  fortnight  as 


Fig.  161. 
Gram  Caterpillar. 
{Twice  magnified.) 


PP,  Chloridea  olsoUta^    F.     (Noctuidae.)     The  Aipericiin  BpU-worjfl. 


GRAM   CATERPILLAR. 


145 


a  rule,  when  the  caterpillar  descends  to  the  ground,  buries  itself  and  trans- 
forms to  the  chrysalis.  The  moth  emerges  in  as  short  a  time  as  six  days  in 
the  hot  weather,  but  may  remain  over  one  month  or  even  up  to  three 
months  in  localities  where  the  winter  is  cold.     The  shortest  actual  life 


^ 

Fig.  162. 
Gram  Caterpillar.     (Twice  maffnijied.) 

history  is  very  little  over  three  weeks  when  the  temperature  is  high 
and  food  plentiful.  This  species  attacks  a  great  variety  of  plants  but 
is  eliiefly  known  as  a  pest  upon  gram,  which  it  attacks  severely. 

Where  the  winter  is  mild,  the  caterpillars  are  found  throughout  the 
season  on  gram,  and  there  may  be  more  than  one  brood  in  this  crop. 
"Where  the  winter  is  colder,  the  moths  emerge  from  hibernation  and 
attack  the  gram ;  this  occurs  in  Behar  in  late  February  or  early  March 
in  normal  years ;  if  many  moths  come  out  then  and  lay  eggs  on  the 
gram,  there  may  be  a  considerable  loss.  From  this  time  till  the  followino- 
November  there  is  a  succession  of  broods  on  various  plants. 


Fig. 163. 
On  the  right  one  caterpillar  eating  another^ 


Gram  Caterpillar  and  JPvpa. 

Opium    [Pajaver   somniferttni)    is   much   attacked,    the    caterpillars 
laling  the  capsules;  tobacco  seed  capsules  are  eaten,  as  also  the  pcds  of 


146 


PE3TS    OF    LEGUMtNOUS    CROPS. 


till-   [Gajanm  indlcm),   tlio    fi-iiits   of   tomato   and   the   sosds  o£   bajra 
[Pennisetum  typJi.oideum)  and  sunflower  [rLeliinthits  sp.). 


V 


■^. 


;.H 


^m.1 


Fig.  164. 
Fupa  and  3Ioth  of  Oram  Caterpillar. 


(3Iaffnified  twice.) 


The  leaves  of  the  indigenous  indig-o  {Indigo/era  sumatrana) ,  oilneevne 
{Medicago  sativa),  o£  maize  and  the  wild  dhaiiira  are  its  food-plants  at 
different  seasons  of  the  year  ;  it  is  beheved  to  be  the  caterpillar  attack- 
ing the  ganja  plant  {Ca?inalis  sativa),  and  there  are  many  records  of 
rather  doubtful  food-plants,  in  Indian  Museum  Notes.  The  above  is 
only  a  ijartial  Hst  of  its  food-plants,  the  moth  having  been  actually 
reared  from  caterpillars  found  feeding  on  each  of  these  plants. 

With  this  great  Hst  of  food  plants,  the  moth  presumably  finds  little 
difficulty  in  laying  eggs,  and  the  pest  can  thus  live  at  all  seasons  of  the 
year.  In  America  the  insect  attacks  the  bolls  of  cotton,  a  habit  never 
recorded  against  it  in  India.  Its  attacks  on  gram,  on  opium  and  perhaps 
on  ganja  are  important  on  the  whole,  though  perhaps  rare.  The  cater- 
pillars are  noticeable  for  their  colour  variations,  and  it  is  impossible  to 
describe  them.  Green  is  the  basis  of  the  colouring  with  brown  stripes ; 
or  brown  almost  obscures  the  greens  or  blends  to  form  a  variety  of 
neutral  tints.  Another  feature  is  their  carnivorous  habits  ;  they  devour 
one  another  readily  when  shut  up  together  or  when  food  is  scarce,  and 
the  artist  has  attempted  to  depict  this  (fig.  163).  They  are  also  note- 
worthy for  their  feeding  habits.  As  a  rule  they  feed  on  pods  or  capsules, 
stretching  in  from  outside  to  reach  the  seeds  and  never  going  inside 


GROUNDNUT  PESTS.  l47 

the  pod ;  having  eaten  one  seed  they  move  down  the  pod  and  eat  in 
opposite  another.  The  species  is  known  from  every  continent  and  has 
become  extraordinarily  omnivorous. 

There  is  no  trustworthy  record  of  tliis  species  behaving-  as  a  surface 
caterpillar  or  '  cutworm/  though  it  is  possible  it  may  do  so ;  nor  does  it 
often  appear  to  come  in  largo  swarms  and  move  from  field  to  field.  It  may 
be  characterised  as  a  pod  and  fruit  caterpillar  becoming  a  typical  leaf-eating 
caterpillar  only  when  it  must  do  so. 

It  is  doubtful  if  any  further  treatment  than  hand-picking  is  ever 
possible  or  desirable  except  in  cases  of  bad  attack  on  small  areas  of 
experimental  cultivation,  where  spraying  may  be  necessary.  The  cater- 
pillars are  large  and  should  certainly  be  hand-picked  in  early  gram  and 
opium  in  order  to  prevent  the  later  brood  from  being  very  large. 

Minor  Pests   of  Groundnut. 

Groundnut  is  on  the  whole  fairly  immune  from  insect  pests  but  is  injured 
by  hairy  caterpillars  (pages  161-62) .  These  caterpillars  have  a  predilection 
for  groundnut,  and  where  they  are  abundant  will  destroy  a  field  in  a  very 
short  time.  In  districts  where  hairy  caterpillars  are  found,  the  crop  should 
be  protected.  Another  common  insect  which  likes  the  groundnut  is  the  big 
cricket,  whose  habits  are  described  elsewhere  (page  224). 

A  small  black  caterpillar  webs  up  the  leaves  and  lives  within  the  webbed 
shoot;  this  is  not  destructive  but  is  likely  to  be  thought  a  serious  pest. 
White-ants  greedily  attack  groundnut  and  may  be  a  very  serious  pest.     The 


Fig.  165. 
Moth  of  Q roundnut  Hairy  Cater fiUar.     (Magnified  txvice) 

J.2 


liS 


PESTS    OF    LEGUMINOUS    CROPS. 


leaf -miner  ^  of  g-vonndniTt  in  South  India  and  Ceylon  is  a  pest  wliich  becomes 
f»f  importance  only  wlien  tlie  climatic  conditions  are  abnormal  and  favour  it. 


Pests  of  Sann  Hemp. 

The    Sann  hemp   {Grotalaria  juncea)    is  very  commonly  attacked  by 
three    species   of    hairy    caterpillars    which    come 
in    large    numbers     and    eat    the    leaves.     These 
caterpillars   are    much    alike     with  slender    bodies 
covered    in    short   hairs,    the   usual    colour   being 
black  or  brown  with  yellow  or  white    (fig.  168). 
The  life  history  is  much  the  same  in  the   three 
the  moth    lays    a   mass   of   small    white 
clusters     on     the     lower    side    of    the 
these    hatch    in    three    or   four   days    to 
small    dark     caterpillars    which    feed    voraciously 
on   the   leaves.      They   rapidly   grow   larger    and 
in     a     fortnight     are    full    grown,     when     they 
themselves      in     the      soil    with    a     light 
round    them    in    order    to    pupate.     The 
emerges    after    four     to    six     days.     The 
are       characteristic  ;       all      are      bright 
and    they     can    be    seen    in    the    fields 
to    plants    or    fluttering    about    in   the 
The     commonest     species^    is      white, 
speckled  with  red 
and    black    ( figs. 
166-67);  another  3 
is   a   brilliant 
orange    with 
black    speckles ; 
the      third  *     has 
the  fore- wings   a 
dull  red  with 
black     speckles 
edged  with   gold, 
the      hind-wing 
red     with     black 
spots. 


Fig.  166. 

The  Hed  Spoffed 

Ermine  Moth. 

{Magnifecl  fivo  and  a 

half  times.) 


species ; 
eggs    in 
leaves  : 


bury 

cocoon 

moth 

moths 

coloured 

clinging 

daytime. 


Fig.  167. 
The  Hed  Spotted  JErmine  Moth. 
{Magnified  two  and  a  half  times.) 


1 273.  Anacampsis  neneria.     Meyr.     (Tineida\) 

'  137.  Utetheisa  pulchella.     L.     (Hypsidse.) 

s    56.  Argina  cribraria.     CI.     (Hypsidse.) 

^    55.  A-rgina  syringa,     Cr.     (Hypsidsg.) 


MuNG  tk&ni 


iti) 


Tlic  moths  lay  their  eg-g-s  also 


Fig.  168. 
Saii'if  C'a(erj)illar.     {Ilagnijied  twice.') 


on  wild  plants,  breeding"  particularly 
upon  leguminous  plants.  There  are 
several  broods  in  the  year,  the  tirst 
in  March  or  April,  the  second  in 
June  or  July,  when  the  bulk  of  the 
caterpillars  are  found  on  the  sann 
plants. 

The  great  safeguard  against 
these  pests  lies  in  clean  cultivation, 
thus  affording-  them  no  food-plants 
at  times  when  sann  hemp  is  not 
available.  It  is  also  possible  to 
collect  the  clusters  of  eggs  and  the 
newly  hatched  caterpillars  if  a 
sharp  watch  is  kept  when  moths 
are  seen  in  the  field.  Nothing  can 
be  done  to  a  crop  that  is  once 
badly  affected  except  to  spray  lead 
arseniate. 

Sann  is  also  attacked  by  a  small 
brown  flea  beetle,  which  eats  holes 
in  the  leaves ;  the  beetle  does  little 
harm  but  it  is  likely  to  be  thought  a 
serious  pest. 


Other  Pests  of  Leguminous  Crops. 

Muug  {Pkaseolus  nmngo)  is  attacked  by  the  caterpillars  of  the 
moth  *  figured,  which  eat 
into  the  base  of  the  pods 
and  destroy  the  seeds ;  the 
caterpillar  remains  within 
and  eats  seed  after  seed 
until  it  is  full  fed,  when  it 
pupates  in  the  ground. 
This  form  of  damage  is 
very  characteristic  and  the 
pest  easily  found.  It  is  as 
yet  doubtful  how  far  this 
pest  occurs  generally,  as  it 
has    not    been    commonly 


Fig.  169. 
Muug  Motli.     (Magnified.) 


^  2'61.3Iarucafeiiulalis.     Gey.     (PyralidsD.) 


15U  tESTS  OP  LEGUMINOUS  CKOl'S. 

reported ;  probably  no  remedies  are  required  and  no  easy  way  of  checking 
it  is  yet  known. 

Soybean  {Glycine  sot/a)  suffers  from  surface  grasshoppers  when  eiuitc 
young',  from  leaf-eating-  caterpillars  of  several  kinds  as  it  grows  larger. 
Except  in  places  where  the  conditions  are  suitable,  the  crop  is  likely  to 
suffer  much  from  these  pests. 

Indigo  is  attacked  by  a  variety  of  insects,  none  of  which  appear  to 
be  of  very  great  importance.  An  aphis '  and  a  small  scale-hke  insect,^ 
which  gather  in  abundance  on  the  shoots,  are  pests  which  weaken  the 
plant  and,  should  the  latter  not  be  healthy,  will  seriously  damage  it.  The 
hJierwa  of  Behar  is  a  pest  of  indigo  as  of  other  crops  grown  where  these 
insects  thrive  (page  227).  Caterpillars  of  many  kinds  attack  indigo  as 
they  do  most  luxuriant  crops,  and  the  indigo  plant  naturally  suffers  more 
as  it  is  grown  at  a  time  when  other  vegetation  is  not  available.  It  is 
worth  noting  that  the  Java-Natal  variety  of  indigo  suffers  less  than  the 
other  varieties  of  indigo  generally  grown  in  Behar.  Little  is  known  of 
these  caterpillars  and  none  appear  to  be  specific  pests  of  indigo. 

>  83.  ApUs  cardui.     Lian.     (Apliidse.)     |    2  Psi/lla  isitis.     Buckt.     (Psyllidge.) 


CHAPTER  Xil. 

PESTS  OF  MISCELLANEOUS  FIELD  CROPS. 

THE  number  of  miscellaneous  field  crops  in  India  is  so  lar<^-e  that  the 
pests  are  probably  numerous.  However^  not  very  much  is  at  present 
known  of  the  pests  of  minor  crops,  and  a  number  of  insects  can  be 
omitted  because  they  come  into  well  defined  classes  of  pests  not  needing 
individual  discussion.  Pests  of  these  crops  are  likely  to  be  more  local 
and  far  more  varied  than  is  at  present  believed.  The  few  that  are  dis- 
cussed here  are  general  in  the  plains,  so  far  as  their  crops  extend.  Very 
many  new  ones  remain  to  be  found  and  among  them  many  very  interest* 
ing  insects  peculiar  to  India. 

Jute  Pests. 

The  insect  pests  of  the  jute  crop  {Corchoms  olitorius  and  C.  cap-mta- 
ris)  are  as  yet  but  little  known.  A  small  black  weevil  ^  breeds  in  the 
stems  of  the  jute,  the  grub  being  found  tunnelling  near  the  axils  of  the 
leaves.  The  grub  is  a  very  small  white  insect,  legless,  with  the  usual 
biting  mouth-parts ;  it  makes  small  tunnels  in  the  jute  stem,  causing  the 
plants  to  become  stunted  and  wither.  In  some  cases  one  grub  is  foimd 
to  almost  every  leaf ;  the  tunnels  extend  about  an  inch  up  and  down  the 
plant,  and  about  half-way  across  the  stem.  The  perfect  insect  is  a  very 
small  black  weevil  with  long  slender  beak  ;  it  is  found  eating  holes  in 
the  leaf  of  the  jute  plant.  Nothing  more  is  known  of  this  pest,  which 
was  found  on  jute  in  Bengal  by  Purushottam  G.  Patel. 

A  pest  of  jute  grown  experimentally  in  Behar  is  a  greeu  semi-loopilig 
caterpillar  ;  the  first  pair  of  prolegs  is  reduced  in  size,  the  body  and 
head  green  ;  two  lateral  stripes  of  white  run  from  head  to  tail  and  there 
are  numerous  black  spots  with  white  edges  on  each  segment.  This  insect 
lives  on  the  top  of  each  plant,  eating  the  leaves  and  eventually  destroying 
the  bud,  so  that  the  growth  of  the  main  shoot  ceases.  It  has  been  found 
only  on  jute  and  is  apparently  a  specific  pest  of  this  crop.* 

Jute  also  suffers  from  hairy  caterpillars  (pages  161-62).  Germinating 
jute  is  attacked  by  the  ground  grasshoppers  (pao-e  221),  and  before 
sowing  it  is  advisable  to  clear  grasshopper-itifested  land  of  them. 

'  212.  Apiou  sp.     (Curculiouidffi.) 

2  229.  Cosmophila  salulifera.    Guen.     (Noctuidte.) 


l53  PESTS    OF    MISCELLA.NBOUS    PIBLD    CROPS. 

The  Mustard  Sawfly.i 

Mustard,  rape,  cabbage  and  other  cruciferous  plants  are  eaten  by 
the  larva  of  one  of  the  few  plant-feeding  H^/metioptera  known  in  India. 
This  larva  is  a  black  caterpillar-like  insect ;  it  may  be  distinguished  from 
the  true  caterpillars  by  having  eight  pairs  of  sucker-feet  instead  of  five ; 
it  is  a  small  insect  not  more  than  half  au  inch  long,  of  a  dull  black  colour ; 
the  skin  has  the  appearance  and  feel  of  velvet. 

It  is  a  pest  to  field  cultivation  of  mustard,  rape,  etc.,  as  also  a  more 
serious  enemy  to  tlie  cabbage  and  radish  crops  grown  by  market 
gardeners.  The  larva  feeds  in  the  morning  and  evening,  descending  to 
the  ground  by  day.  When  full  fed,  it  makes  a  slight  covering  of  silk 
between  two  leaves  and  turns  into  the  pupa,  from  which  the  perfect  insect 
emerges  in  10  to  12  days.  The  imago  looks  like  a  fly,  with  a  rather  short 
thick-set  body  marked  in  black  and  orange  and  with  two  pairs  of  dark 
wings.     It  is  a  very  inconspicuous  insect  but  may  be  caught  in  the  fields. 

The  female  lays  her  eggs  singly  in  the  tissue  of  the  margin  of  the 
leaf,  splitting  the  edge  and  depositing  an  eg^  inside.  There  are  several 
broods  in  the  year  and  the  larva  continues  feeding  in  the  cold  weather 
upon  the  rabi  crops.  It  is  rarely  destructive  where  a  large  area  of 
cruciferous  crop  is  grown  :  when  it  infests  small  plots  or  garden  cultiva- 
tion it  may  cause  a  large  loss.  Dusting  lime,  ashes  or  soot  on  the  plants 
has  a  deterrent  effect  for  market  gardens  :  this  is  the  simplest  precaution. 
Lime  or  road  dust  mixed  with  kerosene  is  better  than  ashes.  The  same 
applies  to  field  crops ;  only  small  areas  are  affected  and  in  them  a  good 
dusting  with  any  of  these  mixtures  is  sufficient  to  check  the  pest.  The 
cultivator's  practice  of  collecting  the  larvae  by  hand  in  an  earthen  pot  and 
carefully  liberating  them  outside  the  field  is  of  course  a  useless  precaution ; 
the  larvae  simply  go  into  the  ground  and  crawl  back  into  the  field  as  soon 
as  it  is  dark.  This  insect  has  been  found  in  widely  separated  localities  in 
India  and  is  probably  of  general  occurrence. 

The  Diamond  Back  Moth.^ 

In  several  parts  of  India  crops  of  cabbage,  mustard,  radish  and  similar 
plants  have  been  attacked  by  the  little  green  caterpillars  of  this  moth. 
The  leaves  have  holes  in  them  and  present  a  withered  appearance,  being  in 
some  cases  eaten  almost  completely.  The  pest  is  familiar  to  those  who 
grow  these  crops,  and  the  cultivators  round  Surat  collect  the  caterpillars  in 
water  and  throw  them  outside  the  fields.     The  pest  is  probably  a  common 

'  54.  Athalia  proxima.     Kl.     (Tcnthrcdinida;.) 
2    3.  Plutella  maoiUipennis.     Curt.     (Tiucida;.) 


DIAMOND    BACK    MOTH. 


153 


one,  but  as  it  attacks  plants  which  are  grown  chiefly  on  small  areas  near 
towns,  it  does  not  rank  as  an  important  pest  and  has  escaped  notice. 

Life  Hisfort/. — The  moth  lays  small  white  eg-gs  on  the  leaves  ol:  the 
plant  on  the  under  side.  From  these  eggs  come  the  caterpillars,  slender 
green  creatures,  thick  in  the  middle,  which  feed  upon  the  tissue  of  the  leaf. 


Fig,  170. 
Diamond  Back  Moth.     {Magnified.) 

not  biting  it  through  but  eating  off  the  lower  surface.  These  portions  of 
the  leaves  wither  and  holes  appear  in  a  short  time.  The  caterpillar  is 
about  half  an  inch  in  length  when  full  grown,  the  head  is  small,  the  body 
almost  devoid  of  hairs.  There  are  the  usual  three  pairs  of  legs  and  five 
pairs  of  sucker-feet.  The  caterpillar  lives  and  feeds  for  about  a  fortnight 
and  then  constructs  a  very  beautiful  cocoon  of  white  silk.  The  cocoon  is 
very  light,  of  a  fine  texture,  and  the  green  chrysalis  is  visible  within. 
This  is  the  resting  stage,  the  chrysalis  remaining  motionless  inside  for  about 
one  week,  becoming  a  little  darker  in  colour.  The  moth  then  emerges.  It 
is  very  small,  nearly  half  an  inch  long  when  the  wings  are  folded,  with  an 
expanse  of  two-thirds  of  an  inch  across  the  open  wings.  The  prevailing 
colour  of  the  wings  and  body  is  brownish  grey ;  the  fore-wings  have  darker 
spots  and  a  light  line  along  the  inner  edge.     When  the  fore-wings  are 


154 


PESTS    OP    MISCELLANEOUS    FIELD    GROPS. 


Fig,  171. 

Ijiamoml  Back  Moth. 

{Natural  size  and  magnified.) 


folded,    the    light     marks   on    the    wings   come  together  forming    tlie 
characteristic  diamond  marks  along   the   upper   surface,  from  which  the 

moth  takes  its  name.  The  moth  may  be 
seen  in  the  fields  flying  from  plant  to 
plant  or  resting  on  the  plants.  There  are 
several  broods  in  the  year,  overlapping  irre- 
gularly, so  that  insects  of  all  ages  are  found 
at  the  same  time.  Probably  there  are  at 
least  eight  and  possibly  twelve  generations 
in  a  year,  the  insect  being  active  through 
the  cold  weather  and  continuing  its  life 
history  as  at  other  times. 
JRemedies.— The  pest  is  a  serious  one  to  growers  of  cabbage,  mustard, 
radish,  and  similar  crops  raised  for  sale  in  the  bazaars.  The  cabbage 
crop  suffers  heavily,  the  plants 
being  frequently  badly  attacked, 
the  leaves  spoilt,  and  the  crop 
unsaleable.  The  cultivator's 
remedy  of  picking  the  larvae  is 
effective  but  very  tedious.  Better 
results  are  obtained  with  spray- 
ing, and  the  simple  tin  hand 
sprayer  made  in  the  bazaar  at  a 
cost  of  rupee  one  annas  twelve  is 
eminently  adapted  for  this  work. 
The  best  insecticide  is  Messrs. 
McDougal  &  Co.''s  Insecticide  and 

Fun  gicide.  Kerosene  emulsion  is  effective  and  also  py re- 
thrum  powder  (or  Keatiug's  insect  powder)  used  as  a 
stomach  poison  at  the  rate  of  1  oz.  to  1  gallon  of  water. 
Where  such  work  is  done  intelligently,  the  use  of  lead 
arseniate  is  by  far  the  best  remedy,  but  owing  to  its 
poisonous  effect  if  applied  in  excessive  quantities  this 
insecticide  cannot  be  generally  applied.  Where  spraying 
is  not  possible  a  dressing  of  ashes,  applied  by  hand  to 
the  underside  when  the  plants  are  wet,  is  effective  in 
preserving  the  leaves  from  the  caterpillars.  A  good 
and  safe  application  is  tobacco  and  soap  or  tobacco 
decoction,  made  by  soaking  refuse  tobacco  in  cold  water 
at  the  rate  of  1  lb.  to  5  gallons  and  adding  soap  suds 
made  by  mixing  |  lb.  soap  in  1  gallon  of  water. 


Fig.  172. 

Semi-loo;per  Calerpillar  that  eats  cabbage. 

{Magnified  four  times.) 


Fig.  173. 

Pupa  of  Cabbage 
Semi-looper,  as  found 
on  cabbage  leaf  under 
a  silken  iceb. 


ilkVt  PESTt^. 


l55 


Minor  Pests  of  Mustard,  Rape,  etc 

Cruciferous  plants  also  suffer  from  the  attacks  of  other  insects 
which  are  not  specific  pests  but  come  casually.  More  than  one  species 
of  caterpillar  can  be  reared  from  mustard, 
cabbage,  rape,  etc.,  and  the  cabbage  crop  in 
particular  suffers  from  the  presence  of  green 
semi-looper  caterpillars  ^  which  eat  holes  in 
the  leaves.  The  mustard  aphis  is  also  a 
serious  pest,  attacking'  mustard,  rape,  sarson, 
etc.,  when  grown  as  a  rabi  crop.  This  aphis 
appears  first  on  the  young  plant,  increases 
with  enormous  rapidity,  and  clusters  on  the 
pods  and  stems.  A  weak  crop  becomes  ex- 
hausted and  unable  to  bear  seeds  (page  2'39). 
The  painted  bug  (page  333)  is  a  very  minor 
pest  of  these  crops,  in  peculiarly  favourable  seasons  becoming  very  abun 
dant  on  late  sown  mustard. 


'^v,-*^'" 

TisS^ 

/75=Sr*^ 

/    H-<     ■- 

y 

'  ,  t  ' 

Fig.  174. 
Calbage  Molh. 


Via.  175. 

The  Rape  Aphin. 

a.  Wingless  female,     b.  Nymph,     c,  Winged  female.     {Magnified  twelve  times.) 

^  loo.  Fliiski  signata.     F.     (NoctuidsB.) 


156  PESTS    OF   MISCELLANEOUS    FIELD    CEOFS. 


Tobacco  Stem  Borer, 

The  most  serious  pest  of  growing'  tobacco  is  a  small  whitish  caterpillar, 
which  is  found  tunnelling  in  the  main  stem,  causing  a  peculiar  gall-like 
swelling.  The  caterpillar  enters  at  the  axil  of  a  leaf  or  tunnels  down  the 
mid-rib  of  the  leaf  until  it  reaches  the  stem  ;  apparently  it  hatches  from 
an  egg  laid  on  the  stem  or  on  the  leaf,  but  this  egg  has  not  been  found. 

Having  entered  the  main  stem,  it  tunnels  in  the  tissues,  which  swell 
and  undergo  abnormal  growth,  producing  a  distinct  and  characteristic 
knot.  Within  this  swelling  the  caterpillar  lives  until  it  is  full  grown, 
when  it  prepares  an  exit  hole  for  the  future  moth  and  turns  to  the  pupa 
inside.  The  moth^  is  a  small  brown  insect,  the  wings  narrow  and 
fringed,  not  easily  distinguishable  from  the  many  small  moths  of  this 
family  which  are  found  in  the  fields. 

Tobacco  is  a  crop  of  which  great  care  is  taken  during  the  growing 
period,  so  that  cultivators  are  aware  of  this  pest ;  when  they  find  this 
swelling,  they  make  a  cut  into  it  with  a  knife,  believing  that  the  admis- 
sion of  air  will  destroy  the  insect.^  Apparently  the  pest  is  not  injurious 
in  healthy  vigorous  tobacco  but  is  worst  in  a  season  of  drought.  It  is 
common  in  various  parts  of  India  and  Mr.  Green  reports  it  from  Ceylon. 
Where  the  pest  is  seen  so  late  that  the  emerging  moths  could  not  produce 
a  new  generation  in  the  tobacco,  only  plants  that  are  useless  should  be 
removed  and  burnt.  No  treatment,  except  perhaps  that  of  cutting  open 
the  plants,  can  check  the  insect  in  the  stem.  The  pest  can  be  looked  for 
in  experimental  tobacco  cultivation,  where  varieties  are  grown  side  by  side, 
and  causes  a  considerable  amount  of  harm  under  these  circumstances. 

Tobacco  Caterpillars. 

Leaf-eating    caterpillars    attack    tobacco   and  a    small  number   may 

do  a  large  amount  of 
actual  damage  by  eating 
holes  in  the  leaves.  The 
most  abundant  of  these 
is  a  dark  brown  cater- 
pillar, common  through- 

„      ,,^  out  India,  which  is  the 

Fig.  176.  ' 

Tobacco  Leaf  Caterpillar.  larva  of  a  common  moth.* 


^  76.     Gncrimoschema  heliopa.     Low,     (Tineidsc.) 

2  For  this  aud  other  facts  about  Gujarat  tultivators,  I  am  indebtedlto  Puruahottam  Patel, 
first  fieldmau. 

3  53.  Prodenia  litioralis.     Boibd.     (Noctuidse.) 


TOBACCO    PESTS. 


157 


The  life  history  is  similar  to  that  of  other  moths,  the  eg-g-s  being 

laid  on  the  plant,  the  caterpillars 
feeding"  on  the  leaves,  the  pupa 
lying  in  the  earth  without  a 
cocoon,  the  moth  lying  hidden  by 
day  and  emerging  at  dusk.  In  the 
hot  weather  or  rains  the  whole 
life  history  is  passed  in  about  a 
month  ;  the  insect  liibernates  as  a 
pupa  or  larva,  emerging  in  March. 
If  tobacco  is  not  available,  the 
caterpillar  attacks  a  variety  of  crops 
and  is  a  pest  in  gardens  (see  page 
181). 
Another  species  attacking  tobacco  is  a  green  caterpillar,  with  a 
similar  life  history ;  it  is  a  common  insect  in  the  plains,  the  moth  ^  being 
closely  similar  to  that  of  the  Gram  Caterpillar,  both  being  of  the  same 
genus.  When  the  tobacco  is  young,  an  application  of  lead  arseniate 
does  good,  poisoning  all  caterpillars  that  feed  on  it.  This  application 
cannot  be  made  to  plants  that  have  large  leaves  and  are  within  a  short 
time  of  ripening,  as  the  arsenic  might  remain  on  the  leaves.  A  fort- 
night before  cutting  is  the  very  latest  date  on  which  arsenic  can  be 
safely  applied.  In  such  a  case  nothing  but  hand-picking  is  possible, 
and  a  careful  watch  must  be  kept  for  such  caterpillars  in  the  last  growth 
of  the  tobacco  plants. 


Fig.  177. 
Moth  of  Tohacco  Leaf  Caterpillar, 


Minor  Tobacco  Pests. 

Surface  grasshoppers  are  commonly  found  attacking  newly  set  out 
plants  of  tobacco,  eating  the  leaves  and  destroying  the  young  plants. 
Even  if  the  plants  are  not  killed,  the  crop  becomes  very  uneven.  To 
check  this  the  grasshoppers  should  be  removed  before  transplanting  ; 
where  possible  the  transplainted  seedlings  shovild  be  dipped  in  the  lead 
arseniate  mixture  used  to  poison  the  leaves  ;  the  young  plants  grow  quite 
well  and  regularly  (page  220). 

Crickets  are  also  found  attacking  young  tobacco,  and  where  this  is  a 
valuable  crop,  the  ravages  of  the  large  crickets  may  be  important 
(page  224). 

The    seed   capsules   are   eaten   by   several  caterpillars,  including  the 

'  158, 1  Chloridea  assulfa,     Gueii.     (Noctuidffl.) 


158 


PESTS   OF    MISCELLANEOUS    FIELD    CROPS. 


omnivorous  Gram  Caterpillar  (pag-o  144).  This  form  of  attack  may  be 
watched  for  and  the  caterpillars  picked  off  if  seed  is  required,  as  these 
insects  may  soon  clear  a  plant  of  the  whole  of  its  seed. 


Caterpillars 


Castor  Pests. 

Castor  is  in  general   a  healthy   i)hwit    with  few   pests. 
are  fond  of  it  and  sometimes 

come  in  vast  numbers,  clear-       ^^         .d*^^^^B^ 
ing  the  plants  of  leaves  in 
a   very  short   time.      Three 
species  are  represented,  being*  Fig.  1V8. 

totally     distinct    and      easily  The  Smooth  Castor  Caterpillar. 

1  (Maqnified  fioice.) 

recognised.  ^     ^   j 

The  Smooth  Castor  Caterpillar  is  a  long  slender  caterpillar  of  a 
dark  colour,  with  longitudinal  stripes  of  red  and  white ;  it  has  the  usual 
five  pairs  of  prolegs,  the  first  being  reduced  in  size  ;  at  the  hind  end 
there  is  a  small  blunt  paired  process  on  the  dorsal  surface.  The  cater- 
pillar walks  with  a  semi-looping  motion.  This  caterpillar  pupates 
in  a  fold  of  the  leaf  in  a  light  cocoon.  The  life  history  is  short, 
occupying  about  five  weeks,  and  there  are  several  broods  in  the  year. 
The  moth  *  is  figured  here  ;  it  is  common  throughout  India,  and  the 
caterpillars  often  appear  in  hordes,  strip  the  plants  and  disappear. 
The  Hairy  Caterpillar  also  feeds  upon  the  leaves  and  is  found  in  clusters 
at  the  base  of  the  stem  from  whence  it  climbs  up  the  plant  to  feed.  The 
full  grown  insect  is  over  two  inches  long,  clothed  in  dense  hair  and  look- 
ing like  a  piece  of  blanket.     This  caterpillar  is  not   so  abundant  as  the 

former  species  and  has  other  food- 
plants.  It  pupates  in  a  cocoon 
formed  of  the  hairs  of  the  larva, 
the  moths  *  that  emerge  being 
green  or  yellow,  the  male  much 
smaller  than  the  female.  The  Spiny 
Castor  Caterpillar  is  a  green  cater- 
pillar, the  body  covered  with 
branched  spines,  the  head  with 
two  long  processes  bearing  spines. 
Moth  of  Smooth  Castor  Caterpillar  shoioing  It  feeds  upon  the  leaves  of  the 
upper  and  lo^ver  surf  ace  of  ^cings.  ^^^^^^      ^^^       pupates     by     hanging 

itself  from  the  leaf;   the  pupa  is  greyish  brown,  with  a  flat  hood-like 

^    52.  Ophiusa  melicerte.     Dr.    (Noctuidae.) 
^  205.  Tralala  vishmi.    Lef.    (I^ymantriidoe.) 


CA-STOU   PESTS. 


159 


structure  on  the  baok,  similar  to  other  butterfly  chrysalides.     The  imago 
is  a  deep  brown  butterfly/  common  throu<>'hout  India  (fig-.  180). 

These  three  species  attack  castor  at  almost  all  seasons  o£  the  year. 
When  the  egga  are  laid  and  the  caterpillars  hatched,  nothing'  can  be 
done  but  to  destroy  that  brood  by  picking  and  burning  the  infested 
leaves.  The  increase  of  these  insects  is  rapid  and,  if  allowed  to  multiply, 
they  may  come  in  such  vast  numbers  as  to  entirely  strip  the  plants. 
The  smooth  caterpillar  is  the  worst  as  it  feeds  upon  many  wild  plants 

and  suddenly  appears  in  numbers 
out  of  the  jungles,  eating  every 
plant  it  can  find  :  having  finished 
the  castor,  it  starts  upon  other  crop 
plants.  Like  other  Noctuid  cater- 
pillars, this  species  feeds  voraciously 
and  quickly;  the  life  history  is 
short  and  the  reproductive  powers 
of  the  moth  large.  Compared  with 
it,  the  Hairy  Caterpillar  is  harm- 
less, being  slow  in  its  life  history 
and  having  few  broods  in  the 
year ;  and  the  spiny  butterfly  caterpillar  is  a  rarer  insect,  that  appears 
constantly  but  does  not  multiply  at  the  enormous  rate  of  its  successful 
cousin. 

Another  pest  of  castor  is  a  small  caterpillar  found  boring  in  the 
capsules,  destroying  the  seeds.  It  does  a  considerable  amount  of  destruc- 
tion when  well  established  and  is  found  abundantly  in  late  ripening"  castor. 
The  caterpillar  is  easy  to  rear,  a  small  bright  yellow  moth  ^  emerging, 
which  is  speckled  with  black.  The  chief  safeguard  is  in  leaving  no  stray 
plants  for  the  pest  to  breed  in  ;  where  the  crop  of  castor  comes  on  evenly 
the  pest  can  do  little  harm.  When  some  ripens  early  or  is  sown  early, 
or  when  stray  plants  are  left  in  the  fields  and  bear  at  unseasonable  times, 
the  pest  increases.  It  is  best  to  sacrifice  the  early  capsules,  picking  them 
off  and  destroying  them. 


Pig.  180. 
Castor  Bidterflij. 


Til  Sphinx. 

A  large  green  caterpillar,  with  oblique  yellow  stripes  on  the  abdominal 
segments,  is  found  feeding  upon  the  leaves  of  til  (sesamum)  during"  the 
cold  weather.     It  has  a  large  horn  on  the  hind  end  and  grows  to  a  length 

^  15fi.  Ergolis  merione,     Cr.     (Nymphalidse.) 

'  161.  Dichocroeis  punctiferalis,     Gqei;.     (Pj^ralidae.) 


160 


PESTS   OF   MISCELLANEOUS   PIELD   CROPS. 


of  over  two  inches.  This  pest  has  been  found  in  the  Central  Provinces 
attacking"  the  cold  weather  til  and  appears  to  be  fairly  abundant  in  some 
seasons.     The  life  history  is  similar  to  that  of  other  moths  of  this  family. 


Fra.  181. 

The  Til  Sphinx  Caterpillar.     {From  Moore.) 

The  eggs  are  laid  singly  on  the  leaves  of  the  plant,  rather  large 
rounded  eggs  of  a  greenish  white  colour.  The  caterpillars  hatch,  feed  upon 
the  leaves  of  the  plant  and  rapidly  grow  larger.    The  larval  life  is  peculiarly 

long,      occupy- 

ing  about   two 

'     ■  •  j       months,  during 

;  which  the  cater- 
pillars increase 
in  size  till  they 
are  very  large 
and  conspicuous. 
The  full-grown 
caterpillar  is  a 
bright  green 
with  eight 
oblique  yellow 
stripes  on  each 
side ;  the  body 
tapers  'towards 
the  head  and 
the  anterior  seg- 

FlG.  182.  »v,/^v,4-o  o«« 

raents        can 

lEmpty  pupa  co.9e  from  which  the  moth  ,  .        ,    ,      .,, 

emerged,  heioxo,  be  retracted  w;th 


Til  Sphinx. 


TIL  PESTS, 


161 


the  head  drawn  in,  giving  the  insect  a  very  striking  appearance.  The 
laro'C  anal  horn  adds  to  the  curious  effect,  which  accounts  for  the  belief  that 
the  caterpillar  is  venomous.  Actually  it  is  absolutely  harmless  and  safe  to 
handle.  When  full  fed  the  colour  changes  to  a  deep  brown,  and  the  cater- 
pillar then  leaves  the  plant  to  find  a  suitable  place  in  which  to  enter  the  soil. 

This  change  of  colour  is  protective,  the  green  colour  hiding  it  when 
on  the  green  plant,  the  brown  colour  when  it  is  on  the  ground  searching 
for  a  suitable  spot.  It  buries  itself  in  the  soil,  appearing  as  a  pupa  after 
a  period  of  rest.  This  is  a  large  chestnut  brown  insect,  smooth  and 
shiny;  the  figure  shows  the  empty  pupa  case  from  which  the  moth 
above  emerged.  The  pupal  period  lasts  for  two,  three  or  more  months. 
The  moth  is  one  of  the  larger  hawk  moths,^  closely  related  to  the  *  death''s 
head '  moth  of  Europe.  The  head  and  thorax  are  dark,  the  latter  with 
the  *  deatVs  head '  mark,  the  abdomen  is  yellow  with  black  bands  and  a 
dark  stripe  down  the  middle,  the  fore-wing  is  mottled  in  brown  and 
grey,  the  hind-wing  yellow  with  black  bands. 

The  larger  specimens  measure  nearly  four  inches  across  the  expanded 
wings ;  the  moths  are  very  swift  in  flight,  emerging  at  dusk  to  fly 
about  and  seek  the  flowers  from  which  they  obtain  nectar. 

This  species  has  also  been  found  on  val  [BolicJios  lah-lah)  and  has 
alternative  food  plants.  It  is  found  throughout  the  plains  of  India,,  not  as 
an  injurious  pest  but  as  a  common  insect ;  it  has  a  wide  distribution  outside 
India.  The  best  treatment  is  to  pick  the  caterpillars  by  hand ;  they  are  large 
and  conspicuous,  can  be  easily  collected  and  are  most  simply  killed  in  water. 


Minor  Pests  of  Til. 

A  small  white  caterpillar,  black  speckled  and  with  a  touch  of  creamy 
is   found    feeding  


green, 

on  the  leaves  or  the  pods 
of  til.  It  is  not  common, 
though  widely  spread  in 
India  and  has  not  been 
reported  or  found  as  a 
serious  pest.  It  is  the 
larva  of  a  small  red  moth  ^ 
less  than  one  inch  across 
the  expanded  wings, 
which  extends  over 
Europe  and  Asia.   Another 


Fio.  183. 
Hairy  Caterpillar  of  Bihar.    {SligMly  magnified.) 


1  193.  Acheroniia  styx.     Westd.     (Sphingidte.) 

2  Jll.  Antifastra  catalawalis.     Dup.     (Pyralidae.) 


162  PESTS    01'    MISCELLANEOUS    FIELD    CHOPS. 

pest   is  the  hairy   caterpillar  (fig-.  184)   which  devours   so    many   crops. 


Fio.  184. 

Hairy  Caterpillar  of  Bihar.     {Slightly  magnified.) 

No  Other  pests  have  been  found  affecting  this  plant,  though  doubtless  others 
remain  to  be  discovered. 


CHAPTER  Xill. 


PESTS  OF  VEGETABLE  CROPS. 

IN  this  chapter  the  pests  o£  all  vegetable  crops  will  not  be  treated  in 
detail ;  some  few  pests  that  deserve  individual  mention  will  be  grouped 
tog-ether.  In  small  areas  of  vegetable  crops  the  pests  of  field  crops  also 
occur ;  radishes  in  a  garden  are  damaged  by  the  same  pests  as  rape  and 
mustard  in  the  field.  Above  all,  numbers  of  occasional  pests  occur  in  small 
areas  of  garden  crops;  leaf-eating  caterpillars  are  numerous,  plant  lice 
and  mealy  bugs  abundant ;  the  brown  ants  eat  the  cauliflowers,  cockchafer 
grubs  eat  the  roots  of  any  plant,  and  so  on.  Such  numbers  of  insects 
attack  a  vegetable  or  market  garden  that  they  cannot  be  discussed  in 
detail  here. 

Sweet  Potato  Weevil. 

A  small  weevil,!  very  narrow  in  outline,  with  a  conspicuous  straight 
beak,  coloured  in  red  and  blue,  is  found  in 
sweet  potato  tubers  in  the  ground.  All  stages 
may  be  seen  in  the  tuber  and  the  beetle  is 
qu.ite  characteristic. 

This  is  almost  the  only  known  specific 
pest  of  sweet  potato  in  India,  a  cosmopolitan 
pest  found  throughout  the  tropics.  The 
weevil  lays  eggs  singly  on  the  tubers, 
hatching  into  a  small  white  legless  grub 
which  at  once  tunnels  into  the  potato.  The 
grub  eats  its  way  in  the  potato,  filling  the 
tunnels  with  excrement  and  setting  up  decom- 
position. 

The  pupa  is  found  in  the  potato,  in  a  small 
cavity  closed  at  each  end  with  particles ;  the 

imago  when  it  emerges  eats  its  way  to  the  surface  and  escapes. 
The  whole  life  history  occupies  about 

one    month ;   the    broods    succeed  one 

another  quickly  and  the  pest  continues 

to  increase   so   long  as  the  weather  is 

warm.     The  tubers  are  attacked  in  the 

field,  the  beetle  laying  eggs  in  the  thick 

stems  on  the  tubers.     A  badly  infested 

plant    becomes   weak  and  stunted,  the 


Fig.  185. 

The  Sweet  Potato  Weevil. 

{Magnified  four  times.) 

{From  Tryon.) 


Fig.  186. 

The  Siveet  Potato  Weevil. 

{Magnified four  times.) 

{From  Tryon^ 


*  7«    Cylas  tureipennis.     Eohm.     (Curculionidse.) 


Mg 


10+  PESTS    OF    VEGETABLE    CROPS. 

stems  swollen  and  the  leaves  small.  The  symptom  is  one  recognisable 
to  the  trained  eye,  l>ut  not  easily  disting-uished  from  the  appearance  of  an 
unthrifty  stunted  crop.  An  examination  of  the  tubers  on  the  main  stems 
reveals  the  pest  at  once,  even  if  the  beetles  are  not  seen  upon  the  leaves. 

The  result  of  the  attack  is  that  the  tubers  are  converted  into  a  decay- 
ing- mass  unfit  for  food.  A  tuber  on  being  cut  exhales  a  peculiar  sharply 
aromatic  odour,  and  the  tissues  round  the  tunnels  darken  when  exposed 
to  air.  If  left  alone  the  insect  reduces  the  whole  tuber  almost  to  dust. 
Tubers  even  lightly  infested  are  iinfit  for  human  food ;  they  may  be 
crushed  and  fed  to  cattle  if  not  too  much  attacked. 

When  a  crop  is  once  infested,  nothing  can  be  done  to  check  the 
pest;  the  infested  potatoes  must  be  destroyed  to  prevent  the  insect 
breeding.  Sweet  potatoes  should  not  be  grown  twice  running  on  or  near 
infested  land ;  the  pest  must  be  starved  out.  Equally  when  a  crop  is 
infested  and  spoilt,  the  whole  crop  must  be  dug ;  small  infested  tubers 
left  in  the  ground  afford  a  breeding  place  to  the  beetle  and  it  is  thus  able 
to  attack  the  next  crop.  As  a  rule,  a  crop  which  grows  deeply  is  not 
attacked,  and  the  beetles  lay  eggs  only  in  tubers  exposed  on  the  surface^ 
A  deep  rooting  variety  should  be  grown  where  the  beetle  is  prevalent  and 
every  precaution  must  be  taken  to  ensure  the  total  destruction  of  an 
affected  crop. 

Pests  of  Melons  and  allied  Plants. 

Melons,  cucumbers,  pumpkins,  and  the  like  are  moderately  immune 
from  pests,  no  very  important  ones  having  yet  been  found.  The  Melon 
Fruit  Fly  is  discussed  elsewhere  (page  170)  ;  the  best  remedy  against 
this  pest  to  melons  in  Baluchistan  and  the  Punjab  is  to  bury  the  young 
fruits  in  the  earth,  as  is  now  done,  or  to  protect  them  by  means  of  muslin 
bags  from  the  egg-laying  flies.  In  India  generally,  pumpkins,  melons 
and  all  forms  of  cucurbitaceous  fruits  suffer  from  similar  flies  but  not  to 
any  serious  extent.  The  maggots  are  found  in  the  fruits  here  and  there  ; 
the  flies  laying  their  eggs  in  the  young  green  fruits.  For  all  these,  care 
in  the  destruction  of  infested  fruits  is  the  rational  check  on  their  increase, 
and  a  maggotty  fruit  should  never  be  left  to  rot  on  the  ground  and 
breed  flies  as  is  so  often  done. 

The  Epilachna  beetles  are  common  pests  on  pumpkins,  etc. ;  they  are 
universal  in  India,  feeding  normally  upon  wild  plants  and  multiplying 
slowly  on  the  crops.     They  are  discussed  separately  (page  204). 

The  Red  Leaf  Beetle^  is  the  most  general  pest  of  these  plants 
(fig.  233,  page  200)  ;  it  is  found  in  all  varieties,  the  beetle  feeding  among 

•  11,  Aulacofhora  fov0i0ollis,     JCust.     (Chrysomelidae.) 


Melon  pEsts* 


iei 


tlio  leaves  and  damag-ing"  the  young  plants.  This  beetle  is  perhaps  the 
most  comnion  and  abundant  insect  in  the  plains,  met  with  wherever 
there  is  a  cucurbitaceous  plant.  Its  life  history  is  still  unknown. 
Well-established  plants  that  are  growing  freely  do  not  suffer  from  this 
pest,  but  it  eats  young  plants  completely.  Lead  arseniate  is  the  direct 
cure,  but  an  occasional  dose  of  kerosene  emulsion  to  make  the  leaves 
nasty,  or  a  liberal  dusting  with  ashes  or  lime  and  kerosene  keeps  away 
the  beetles  for  the  time  being. 

With  the  red  beetle  is  a  very  similar  insect  ^  with  blue  black  wing 
covers  (fig.  23-i,  page  200)  ;  this  is  rarer  but  still  fairly  common  and 
behaves  just  as  the  red  beetle  does. 

Among  other  pests  the  Banded  Blister  Beetle  (fig.  241)  is  common 
on  the  large  flowers  of  these  plants,  feeding  on  the  anthers  and  sepals. 
It  looks  a  far  worse  pest  than  it  really  is,  as  the  destruction  of  the  flowers 
really  does  not  matter. 

A  single  caterpillar  is  abundant  upon  these  plants,  behaving  as   an 

ordinary  leaf  caterpillar.  This  is  a 
slender  green  caterpillar,  marked  by 
a  stripe  of  white  on  each  side  of  the 
mid-dorsal  line,  and  a  spot  of  black 
on  the  first  two  segments ;  it  grows 
to  a  length  of  one  inch  and  pupates 
on  the  lower  surface  of  the  leaf  under 
a  thin  webbing.  The  moth  2  is 
white  with  a  broad  band  of  black  on 
the  edge  of  the  wing  (fig.  187). 
When  very  numerous  this  is  a  destruc- 
tive insect,  riddling  the  plants  in  a 
short  time.  Where  possible  a  good 
application  of  lead  arseniate  should 
be  applied.  In  other  eases,  only 
Tir  ^1    ^Ti^^',^*^^.      -7  7  laborious    methods   of  hand   picking 

Moth  of  Pumpktn  Caterpillar,  x  o 

{Twice  magnified:)  can  be  USCd. 


Caterpillar  Pests  of  Brinjal. 

Three  species  of  caterpillar  attack  the  brinjal  plant  {Solatium  melow 
gena)  working  in  similar  ways  but  belonging  to  three  distinct  groups 
of  moths.  It  is  difficult  to  distinguish  these  in  the  caterpillar  stage 
and  we  may  consider  them  together. 

^  125.  Aulacophora  excavata.    Baly.     (Clirysomelidse.) 
'112.  Qlyphodes  indica.     Saund.     (Pyralidse.) 


l66 


PESTS    OF    VEGETABLE    CRdP^. 


Fig.  188. 
Brmjal  Fruit  Borer.     {Magnified  three  times.) 


These  caterpillars  bore  tunnels  in  the  stems  and  branches  of  the  plant, 

living"  inside  and  feeding*  upon 
the  tissue   of  the   plant.     They 
are     whitish     coloured    insects, 
smooth    and    generally    similar 
to     other     borer       caterpillars. 
The    eggs    from    which     they 
hatch   are    deposited    upon    the 
plant    singly,    and     the    little 
caterpillar  at  once  bores  into  the  stem.     When  full  grown  the  caterpillar 
pupates,  making  a  cocoon  for  itself  on  the  plant,  on  the  ground  or  more 
rarely  in   the  tunnel  of   the   stem.     The   pupa  stage  lasts   from  eight 
to  twelve  days  in  warm  weather  and  the  moths  emerge.     The  whole 
life  history  occupies  about   one  month  in  the  warm  weather  and  up  to 
three  months  in  the  cold.     These  moths  are  of  very  distinct  appearance ; 
one*   is    a    small    brown    insect,    with    narrow 
fringed    wings  and  sharply   upturned  palps ;    it 
superficially  resembles  moths  such   as  the   Pink 
Boll-worm  Moth   (page  94)  or  the  Cotton  Bud- 
Worm  Moth  (page  100).     We  may  call  this  the 
moth  of    the    stem-borer    caterpillar,   since   the 
caterpillar    is    principally     in    the     main    stem. 
The  other  moths  are  both  white  ;  one^  (fig.  189) 
has  brown  and  black  speckles  on  the  wings,  and 
the  larva  has  a  rather  pinkish  colour   (fig.  188)  ; 
it    is    found    commonly    in    the    fruit    of    the 
plant   and  we    may   call   it    the  "  fruit   borer.''^     The  other  ^  is  slightly 
smaller,  white,  with  a  broad  green  blotch  on  the  wing.     It  is  a  quite 
distinct  insect  and  easily  recognised.     Its  larva  bores  only  in  the  upper 
branches  of  the  plant,  tunnelling  in  the  soft  shoots.    We  may  call  it  the 
"  shoot-borer.'^ 

The  stem-borer  is  found  principally  in  the  lower  part  of  the  stem 
near  the  ground ;  it  attacks  plants  at  all  stages  and  is  a  serious  pest. 
Where  brinjal  is  grown  as  a  long  crop,  quite  thirty  per  cent,  of  the  old 
plants  may  be  attacked  and  killed;  the  plants  wither  suddenly  when 
the  larva  cuts  through  the  cambium  layer  of  the  main  ste^ ;  such 
withered  plants  are  common  in  the  fields  when  the  crop  has  been  grow- 
ing for  some  months.     The  shoot-borer  is  a  comparatively  harmless  insect. 


Fig.  189. 
Brinjal  Fruit  Borer. 


*  2.  Fn&ophera  perticella.     Rag.     (Pyralidje.) 

2  109.  Leucinodes  orbonalis.     Guen.     (Pyialidfe.) 

*  154.  Fullemma  olivaeea,     Wlk,     (Noctuidae.) 


inii^i)!  piisTs.  167 

only  destroyiiii^  isolated  branches  and  not  killing  the  whole  plant.  The 
fruit-borer  attacks  the  fruits  as  they  ripen  and  also  the  shoots;  it  is 
perhaps  the  most  common  and  widespread  of  these  three  species. 

The  treatment  of  all  these  is  the  same,  namely,  destroy  all  affected 
fruits  and  branches.  In  the  case  of  the  stem-borer,  the  cultivator  pulls 
up  the  withered  plants  and  leaves  them  in  his  field.  If  he  burnt  them 
systematically  from  the  very  beginning",  he  would  probably  check  the 
pest,  but  actually  it  increases  steadily  as  his  plants  grow  bigger  until  it 
causes  a  very  large  aggregate  loss. 

The  same  applies  to  the  affected  fruits  and  branches ;  it  is  common 
to  see  the  bored  fruits  left  on  the  ground  or  on  the  plant,  and  naturally 
every  moth  hatching  from  them  means  more  in  the  next  brood.  A  useful 
precaution  where  brinjal  is  regularly  grown,  is  to  destroy  the  wild 
brinjal  and  allied  solanaceous  weeds  which  spring  up  in  the  rains  j 
these  are  the  wild  food-plants  of  these  species  and  help  it  to  increase 
and  multiply  unchecked. 

Bhindi  Pests. 

This  plant  {Hibiscus  esculentus)  is  closely  related  to  cotton^  and  td 
many  plants  grown  in  gardens  for  ornament.  It  is  universally  grown  in 
India  as  a  vegetable,  a  few  plants  here  and  there  in  every  village^  and 
also  as  a  field  crop  mixed  with  other  plants. 

It  has  many  pests,  almost  as  many  as  cotton,  the  pests  of  cottoiil 
attacking  it  as  an  alternative  food-plant,  the  pests  of  wild  malvaceous 
plants  coming  to  it  as  it  offers  plentifid  food  when  other  food  is  not 
available.  The  Cotton-leaf  Caterpillar  (page  06)  is  abundant  on  the 
leaves,  webbing  them  across  and  living  under  the  threads*  It  does  not 
as  a  rule  twist  the  leaves  up  as  it  does  on  cotton.  At  least  three  other 
caterpillars  feed  on  the  leaves,  two  being  peculiar  pests  of  malvaceous 
plants  j  these  emerge  into  moderate  sized  light  yellow  moths,^  the  wings 
marked  with  dark  brown  suffusions. 

The  White  Weevil  and  Green  Weevil  eat  the  leaves  of  bhindi  as 
they  do  of  cotton  and  other  crops  (page  202).  Both  the  Spotted  Boll- 
worms  also  attack  bhindi,  the  larva  boring  into  the  pods  or  into  the 
succulent  stems.  The  Red  Cotton  Bug  (page  10-i)  lives  upon  bhindi 
when  cotton  is  not  available,  feeding  upon  the  seeds  and  breeding  freely 
upon  these  plants.  So  also  the  Dusky  Cotton  Bug  (page  107)  is  found 
in  the  old  open  pods,  sucking  out  the  seeds. 

In  spite  of  all  these  pests,  bhindi  grows  freely  and  yields  well.     A 

little  attention  on  the  part  of  the  cultivator  checks  the  insects,  but  as  the 

^58*  Acontia  transversa.  Guen.  (Noctuidse)  ;  &  117.  Acontia  malvce.  Esper.  (Noctuidic.) 


168 


PESTS    OF    VKGETIbLE   CROPS. 


crop  still  comes,  in  spite  o£  the  pests,  no  attention  is  paid  to  them.  This 
is  unfortmiate,  as  these  insects  on  bhindi  are  also  the  pests  of  cotton 
which  do  much  harm. 

Pests  of  Ginger. 

Two  pests  have  been  found  attacking*  ginger  in  Bengal,  neither 
seriously.  The  ginger  maggot  is  a  white  fly  maggot  found  tunnelling 
in  the  rhizome  of  the  growing  plant ;  these  maggots  resemble  the  usual 
fly  maggots,  being  small  headless  white  insects,  with  mouth-parts  in  the 
form  of  hooks.  They  tunnel  in  the  tissues,  killing  them  and  setting  up 
decay.  The  pupa  is  found  in  the  rhizome  and  the  fly  is  found  walking 
on  the  leaves  of  the  plant.  The  fly  Ms  a  noticeable  insect,  with  long  legs, 
a  long  narrow  body  and  wings  ;  such  flies  are  not  uncommon  but  can  be 
seen  in  any  number  on  ginger  plants.  The  rhizome  should  be  examined 
for  mag'g'ots  and  any  diseased  ones  destroyed. 

The  ginger  caterpillar  is  a  green  caterpillar,  with  a  dark  head,  of 
the  typical  "  skipper  "  form,  which  lives  upon  leaves,  folding  one  over  and 
lying  hidden  inside  the  fold.  The  pupa  is  also  found  on  the  leaf  and  a 
prettily  marked  butterfly  ^  emerges.  As  a  rule  one  caterpillar  is  found  on 
each  plant,  the  butterfly  laying  her  eggs  one  at  a  time.  The  pest  is  easily 
cheeked  by  hand  picking,  the  caterpillars  and  pupae  being  found  in  the 
large  folded  leaves. 

Potato  Pests. 

The  only  specific  pest  of  potato  recorded  is  the  very  common  green 

bug,^  a  cosmopolitan  insect  which  sucks 
the  juice  of  the  plants  and  is  found 
commonly  on  them.  It  is  a  common 
insect  in  the  hills  and  is  readily  checked 
by  hand-picking. 

A  boring"  caterpillar  has  been  reared 
from  potato  plants  in  Dharwar  which 
is  the  Brinjal  Fruit-borer  (page  166). 
A  somewhat  serious  pest  in  Bengal  is  a 
mealy  bug  which  attacks  the  stored 
seed  potatoes,  and  apparently  causes 
them  to  rot.  Seed  potatoes  infested 
with  this  bug  cannot  be  preserved  until 
^,  ^^  ^gQ  the    next   season.     The    treatment    is 

The  Green  Bug.    {Magnified.)  very   simple    and    lies   in    storing  the 


^  2Y\.  Calohata  s\>.    (Muscidac  acalyptratse.)    |   2  215,   Udaspes  folus.    Cram.    (Hesperiidse.) 
*  Nezara  viridula.    L.     (Pentatomidse.) 


i'OTATO  PESTS. 


16^ 


potatoes  in  ashes  or  other  dry  powder,  or  in  examining  them  periodically 
and,  if  infested  with  bug-,  dipping  them  in  a  weak  insecticide  such  as 
kerosene  emulsion.  A  mixture  of  ash,  lime,  flour  or  other  powder  and 
kerosene  dusted  over  stored  potatoes  will  preserve  them  by  destroying 
the  bug. 


CHAPTER  XlV. 


T 


PESTS    OF     FRUIT. 

Fruit  Flies. 

HROUGHOUT   the   tropics,    ripening'   fruits    are   infested  with    the 
maggots    of    flies, 


which  burrow  in  the 
soft  tissues  and  render 
the  fruit  valueless. 
Such  flies  are  of  far 
greater  importance  in 
other  parts  of  the  world 
than  in  India,  possibly 
owing  to  the  different 
manner  in  which  fruit 
culture  is  conducted  in 
India.  Several  species 
are  known  in  India,  the 
Melon  Fly  of  Baluchis- 
tan and  the  Punjab,^ 
the     Peach     Fly^      of 


Fig.  191. 
The  Mango  Flif.     Larva  on  the  right.     {Magnified.) 


Fig.  192. 
Mango  fruit  infested  tvith  maggots. 


'  218.  Carpomyia  ^arcialina.    Big.    (Trypetidse.)  |  »  Rivellia  persica.   Big.    (Trypetidjc.) 


PRUTT   FLIES. 


171 


Fig.  193. 
The  Peach  Fly.     {Magnified.) 


ilanchi,  and  the  Mango  Fly  ^  of  Beliar,  the  United  Provinces  and  other  parts 
of  India  being-  the  more  important  species.  There  are  in  addition  species 
which  attack  the  brinjal,  the  turia,  the  various  melons  and  gourds,  the  fruit 

of  the  akh  {Calotropis  spp.)  and  other  wild 
plants.  These  insects  cannot  be  said  to 
be  known  as  serious  pests;  they  may  be 
so,  as  the  cultivators  do  not  report  such 
attacks  and  it  is  only  rarely  that  they 
can  be  investigated.  The  Mango  Fly  is 
perhaps  best  known,  as  it  attacks  a  fruit 
of  general  consumption  and  is  noticed 
by  many  persons. 

The  life  history  of  fruit  flies  is  gen- 
erally as  follows :  the  female  lays  eggs 
in  the  tissue  of  the  fruit,  piercing  the 
rind  by  means  of  the  ovipositor,  the 
stinff-like  continuation  of  the  abdomen.  A  number  of  small  white  eggs 
are  laid,  which  hatch  in  a  few  days  to  tiny  white  maggots.  The 
maggots  live  on  the  pulp,  making  tunnels  through  it  and  perforating  it 
in  all  directions.  This  period  lasts  about  ten  days,  and  the  maggot 
then  leaves  the  fruit  and  enters  the  earth,  where  it  becomes  a  pupa. 
From  this  the  fly  emerges  after  the  lapse  of  about  a  week.  The 
details  of  this  life  history 
vary  for  different  fruit 
flies,  but  such  are  the 
salient  facts. 

The  Melon  Fly  is  in- 
jurious in  Baluchistan 
and  the  Punjab;  its  life 
history  has  been  recently 
worked  out.^  The  female 
lays  one  or  several 
eggs  (4-7)  singly  or  in 
batches  on  the  rind  of 
the  fruit  in  the  early 
hours  of  the  morning,  a 

very  young  fruit  being  generally  chosen  for  oviposition.  The  eggs  are 
white,  oval  and  elongate,  hatching  in  4<  to  5  days.  The  small  white 
larvse  at  once  bore  into  the  fruit ;  as  they  proceed  into   the  pulp,   the 

^  129.  Bacus  ferriigineus  01.     (Trypetidee.) 

2  Report  of  Lala  Vishvva  Nath  Sahai,  Entomological  Assistaut,  Punjab. 


\ 

.  . 

/ 

fef# 

1 1 

T 

Vl> 

Fig.  194. 

The  Baluchistan  Melon  Fly.     Larva  on  the  right, 

pupa  in  the  middle.     (Magnified.) 


Hi  PESTS    OF   iniJiT. 

passage  fills  up  behind  them  and  a  few  days  after  the  maggots  have 
reached  the  inner  pulp^  the  hole  in  the  rind  closes  completely  up.  When 
several  maggots  are  contained  in  a  single  fruit,  it  gets  stunted  and 
dies ;  if  the  number  is  only  three  or  four,  the  fruit  decays  only  if  the 
maggots  bore  out  through  the  rind. 

When  full  grown  the  maggot  is  about  half  an  inch  long ;  it  pupates 
in  the  fruit  or,  if  the  fruit  is  much  eaten  or  decayed,  in  the  soil.  Pupal 
life  lasts  for  13  to  18  days,  the  whole  life  history  occupying  one  month. 
There  are  two  broods  in  the  melon  crop,  the  first  a  small  one,  the 
second  very  large. 

This  account  of  the  Melon  Fly  is  typical  of  the  whole  group,  with 
small  distinctions.  As  a  rule  eggs  are  laid  in  the  fruit,  not  on  the  rind. 
The  critical  point  in  the  attack  is  the  first  brood ;  if  the  first  flies  can 
be  prevented  from  laying  eggs  or  the  first  larvae  destroyed,  the  immense 
second  brood  is  checked. 

These  flies  have  been  very  carefully  studied  in  other  parts  of  the 
world  where  they  are  very  serious  pests.  We  have,  therefore,  the  experi- 
ence of  other  countries  to  guide  us  in  our  attempts  to  check  the  pest. 
Actually,  two  measures  only  can  be  advised  which  are  adopted  else-, 
where.  It  may  be  taken  for  granted  that  once  the  fly  has  been  allowed 
to  lay  eggs,  the  infected  fruits  are  doomed.  No  possible  treatment  can 
destroy  the  maggots  in  the  fruits.  Also  there  is  no  method  of  destroying 
the  flies  on  a  large  scale  and  so  killing  them  before  the  fruits  ripen. 
It  is  possible  to  prevent  the  flies  from  laying  eggs  by  the  use  of 
netting.  The  flies  only  lay  eggs  on  ripening  fruits,  and  in  South 
Africa  the  fruit  trees  liable  to  attack  are  covered  in  cheap  mosquito 
netting  of  a  fine  enough  mesh  to  keep  them  out.  This  simple  remedy 
is  practicable  where  the  value  of  the  crop  to  be  saved  exceeds  the  cost  of 
the  netting. 

In  addition,  it  is  clearly  wise  to  check  the  increase  of  the  flies  them- 
selves in  the  fruits.  The  early  ripening  fruits  are  naturally  first  attacked 
and  from  them  comes  the  large  second  brood  that  attacks  the  main  crop. 
Every  fruit  that  falls  from  the  tree,  and  every  fruit  that  is  found 
to  be  infested,  should  be  destroyed  to  prevent  the  flies  emerging  and 
multiplying. 

At  the  present  time  an  effort  is  being  made  by  entomologists 
abroad  to  utilise  the  natural  enemies  of  these  flies  and  introduce 
them  to  places  where  they  do  not  at  present  exi^t.  Up  to  the  present 
there  appears  to  be  no  reason  to  anticipate  much  practical  result 
from  this  method  until  a  far  greater  amount  of  investigation  has 
been  made. 


MANGO  HOPPEES.  173 

For  the  Indian  species,  this  Hne  of  enquiry  cannot  be  entered  upon 
until  more  is  known  of  fruit  flies  in  general.  Very  few  enemies  of  fruit 
flies  are  known  in  India  and  very  little  is  on  record  of  the  habits  or  dis- 
tribution of  the  species  discovered.  As  in  other  cases,  if  the  cultivator 
would  take  an  interest  in  his  pests,  seek  for  all  infested  fruits  and 
destroy  them,  much  would  be  done  towards  checking  them.  As  a  rule 
infested  brin jals,  for  instance,  are  plucked  and  allowed  to  lie  on  the  ground 
near  the  plant,  the  natural  result  being  that  the  pest  is  encouraged 
and  allowed  to  multiply  unchecked.  The  same  applies  to  other  crops ; 
maggotty  mangoes  lie  on  the  ground  and  rot,  breeding  a  fine  large 
brood  of  flies  which  lay  eggs  in  every  late  mango  fruit. 


Mango  Hoppers.i 

Mango  trees  suffer  from  the  attacks  of  small  insects,  which  we  may 
call  hoppers,  which  infest  the  flowering  shoots  of  the  tree.  These 
insects  resemble  the  Cicadas  superficially  but  are  much  smaller  being 
one-sixth  of  an  inch  in  length.  They  are  somewhat  wedge-shaped  with 
wings  sloped  at  an  angle  over  the  back.  Large  numbers  are  found 
on  the  mango  trees  throughout  the  hot  weather  but  especially  at  the 
flowering  season  when  there  is  a  flow  of  sap  to  the  flowering  shoots. 
These  insects  pass  through  their  active  life  on  the  tree,  sucking  the 
juice  of  the  soft  shoots  and  causing  them  to  wither.  The  cast  skins 
may  be  seen  in  abundance  on  the  under  surface  of  the  leaves  of  the 
tree.  The  insects  when  young  jump  actively,  when  full  grown  fly  out 
fi'om  the  leaves  when  disturbed.  They  are  rarely  plentiful,  and  their 
increase  appears  to  be  assisted  by  damp  winds,  such  as  the  east  winds  of 
Behar  which  in  some  seasons  blow  in  February  and  March.  The  result 
of  this  increase  is  seen  by  the  withering  of  the  flowering  shoots  and 
consequent  failure  of  the  crop.  Like  other  sucking  insects  these  insects 
excrete  large  quantities  of  sugary  fluid,  which  falls  upon  the  leaves 
below  and  dries,  leaving  a  sticky  shiny  deposit.  When  abundant,  immense 
quantities  of  this  fluid  fall,  which  is  a  symptom  of  the  disease.  There 
is  only  one  effective  treatment  which  must  be  adopted  vigorously ;  this 
is  spraying  with  strong  contact  poison  such  as  crude  oil  emulsion 
or  sanitary  fluid ;  a  large  spraying  machine  fitted  to  a  barrel  with  a 
good  length  of  hose  fixed  to  a  bamboo  should  be  used  so  as  to  reach 
high  up  the  tree,  and  the  spraying  should,  if  possible,  be  done  before  the 
flowers  open. 

^  Jdiocerus  spp.  (JassidsB.) 


174)  PESTS    OF    FRUIT, 

The  Mango  Weevil.^ 

In  many  parts  of  India  ripe  mango  fruits  are  found  to  be  spoilt  by 
the  tunnels  of  an  insect  which,  emerging  from  the  stone,  eats  its  way 
out  through  the  pulp.  The  insect  is  a  short,  thick-set  weevil,  dark  brown 
in  colour,  one-third  of  an  inch  in  length.  When  disturbed  it  draws  its 
legs  together  and  lies  motionless,  feigning  death.  The  grubs  bore  in 
the  kernels  of  the  mango  fruit  when  it  is  growing  large ;  these  grubs 
pupate  inside  the  fruit  and  as  the  mango  ripens,  become  beetles,  eating 
their  way  out  through  the  pulp  of  the  fruit,  which  they  spoil.  The 
beetle  hides  at  once  in  the  bark  of  the  mango  tree,  either  in  a  natural 
crevice  or  in  a  hole  prepared  by  itself.  The  beetle  remains  in  this 
position  apparently  until  the  next  season  and  there  is,  therefore,  but  one 
brood  in  the  year. 

The  weevils  remain  alive  for  very  long  periods  and  are  capable  of 
living  until  the  next  year  when  they  lay  eggs  on  the  mango  flowers  or 
young  fruits.  Weevils  have  been  found  throughout  the  year  on  trees 
whose  fruits  were  infested,  and  it  is  certain  that  they  can  live  over  till 
the  following  year.  They  also  remain  in  the  soil  and  not  always  on  the 
bark  of  tree.  The  treatment  of  this  pest  will  depend  upon  two  precau- 
tions :  destroy  all  infested  fruits  with  the  insects,  and  destroy  the  weevils 
on  the  bark  of  the  mango  tree  in  August.  The  weevils  can  be  found  on 
the  bark  of  mango  trees,  which  accounts  for  the  fact  that  year  after  year 
the  same  tree  is  affected ;  the  weevils  come  out  of  the  fruit,  and  stay  on 
that  tree  till  next  year,  not  flying  or  moving  away.  The  bark  of  trees 
which  bear  infested  mangoes  should  be  well  washed  with  strong  kerosene 
emulsion  or  other  contact  poison,  with  a  view  to  destroying  the  weevils 
found  there ;  this  has  not  been  tested  as  yet  but  is  worth  a  trial.  A 
further  precaution  consists  in  thoroughly  cultivating  the  ground  under 
the  trees,  so  as  to  destroy  the  weevils.  Rai  Bahadur  B.  C.  Basu  has 
found  that  when  the  land  below  infested  trees  is  flooded,  the  trees  are  not 
infested  in  the  following  year. 

The  Lemon  Caterpillar. 

Lime,  lemon,  orange  and  other  citrus  trees  are  defoliated  by 
curiorisly  marked  caterpillars,  which  feed  openly  upon  the  leaves'^ of  the 
plant.  These  caterpillars  hatch  from  small  round  yellow  eggs,  laid  a  few 
at  a  time  upon  the  topmost  shoots  of  the  plants,  where  the  young  cater- 
pillars v/ill  find  tender  leaves  upon  which  to  feed.     They  are  at  first  brown 

^  ?04.     CryfiorJiyncTius  mangijera.     F.     (Curculionidse.) 


LEMON    CATERPILLAR. 


175 


with  white  marking's,  closely  rcsemblinf^  the  dropping-s  of  bii-ds,  and 
doubtless  feed  on  the  leaf  in  an  exposed  position  to  assist  the  resemblance. 
The  head  is  provided  with  two  processes.     When  nearly  full  g-rown  the 


Fig.  195. 
Lemon  Caterpillar,  feeding. 


colour  changes  to  a  vivid  green,  with  lateral  brown  markings  and  the 
caterpillar  now  leaves  its  exposed  j)osition  on  the  leaf ;  when  young*  they 
feed  on  the  quite  small  leaves,  attacking"  larger  ones  as  they  grow  older. 
As  a  rule  only  a  few  are  found  on  each  plant  but  they  do  much  miscliief 
to  small  plants  and,  if  abundant,  entirely  strip  them.  The  caterpillar 
pupates  on  the  plant,  fixing-  itself  by  the  tail  and  by  a  thread  round 
the  body  which  is  fastened  on  each  side  to  the  plant.  The  butterfly^  is 
large  and  conspicuous,  common  throughout  the  plains  (fig"s.  196  and  197). 

^  39,  P<fpilio  demoletis,     li.     (Papilionidse.) 


176  PESTS   OF   PRUIT. 

It  lays  its  eggs  also  on  the  ber  {Ztz9/phns  Ji/Jtcia)  and  other  wild  plants. 


Fio.  196. 
Chrysalis  of  tlie  Lemon  Caterpillar. 


There  are  several  broods  in  the  year^  the  first  in  Aprils  the  second  in 
June,  the  last  in  November,  but  there  is  also  a  brood  in  December  in 
places  where  the  cold  is  not  too  great.  The  simplest  method  of  dealing" 
with  this  pest  is  to  pick  off  the  caterpillars  and  destroy  them.     The 


ORANGE    PESTSi 


.11 


application  of  lead  arseniate  is  effectual,  but  as  there  is  usually  a  succes- 
sion of  egg'-layino;  females,  one  application  is  not  sufficient,  and  it  is 
simpler   to   pick   tliera  by   hand.     Another   butterfly  ^    with   an    almost 


1 

^R 

■ 

■ 

^iTi^^s.v^^^^^ 

^  .^^^B 

1 

'^W^u^ 

ivt^*^^ 

^^■L^.    41k 

^     ^r^^mtbm.: ,  .fl.-  I  ■     JB^k 

f%       ^m.  -.;    1^ 

m^^^^^^^^^^^^^ 

m^mtj'  ft'jisiiiM 

K*i\^ 

I^^^H 

■ 

i 

■ 

Fig.  197. 
Lemon  Butterftj/. 

identical  life  history  is  found  attacking-  citrus  plants  but  is  apparently 
less  common. 


Insect  Pests  of  the  Orange. 

Orang-e  and  other  citrus  trees  all  the  world  over  are  infested  with 
scale  insects  and  mealy  wings,  some  being  extremely  virulent  pests. 
These  are  not  lacking  in  India,  though  they  do  not  work  a  tithe  of  the 
damage  caused  elsewhere.  In  the  Himalayas  as  in  Calcutta,  the  leaves 
are  covered  with  a  small  yellowish  oval  scale  ^  from  which  a  mealy-wing 
fly  emerges  ;  in  Western  India,  a  black  oval  scale  takes  its  place,  belong- 
ing equally  to  the  mealy-wings.  Both  these  species  weaken  the  plant, 
extracting  the  sap  and  slowly  killing  the  branches.  True  scale  insects 
also  infest  these  plants  but  they  are  apparently  rarer.  For  these  pests 
there  is  nothing  better  than  a  good  spraying  with  a  rosin  wash  j  the  whole 
plant  must  be  carefully  sprayed  especially  the  under-surface  of  the  leaves. 

Another  pest  of  the  orange  is  a  large  moth,^  which  pierces  the  rind 
of  this  and  other  fruits   with  its  powerful  proboscis  in  order  to  extract 

'  195.  Fafilio  immvion.  L.  (Papiliniiida;.)    |    "^  Aleurodes  eugenia.  var.  Aurantii.  Mask. 
8  Ophideres  fuUonica.  L.  (Noctuida).) 

N 


178 


PESTS   OP   FRUIT. 


Fig.  198. 
A  typical  Tree-horiiig  Beetle. 


the  sap.     The  insect  is  a  handsome  one,  the  upper  wings   coloured  in 

tones  of  grey,  to  resemble  tree  bark,  the  lower  bright  orange  and  black. 

By  day  this  insect  hides  on  the  bark  of 
trees,  with  the  wings  folded,  coming  out 
at  dusk  to  fly  about.  It  is  attracted  to 
fruit,  feeding  on  the  juices.  This  insect, 
like  many  others,  comes  into  houses  at 
night  and  can  probably  be  trapped  by 
putting  up  a  lantern  in  front  of  a  vertical 
white  sheet,  the  broad  white  light  attract- 
ing it.  This  would  bring  it  to  settle  on 
the  sheet  when  it  could  be  killed.  An 
alternative  possible  method  is  to  give  it 
food  in  the  form  of  jaggery  made  into  a 
syrup  with  water,  mixed  with  a  little 
country  liquor  or  other  intoxicant.  Both 
of  these  devices  are  common  ones  among 
moth  collectors  and  worth  trying  against 
this  pest  when  the  oranges  are  ripe.  As 
the  larva  lives  upon  wild  plants  in  the 
jungle,  nothing  can  be  done  to  check  it. 
Stem-borers   are    reported  to  injure  oranges    in   India  and  may  be 

found  attacking  the  trees.     Such   borers  are  the  grubs   of  beetles ;  the 

beetles  lay  eggs  on  the  bark,  the  grubs  on  hatching  boring  through  the 

bark  into  the  trunk.     They  Hve  in  the  trunk  and  attain  to  a  great  size 

before       pupating,      eventually 

comiiig    out     as    beetles.     The 

beetles   are  long,    slender,  with 

Very      long       antennse.       Two 

species  a;re    known    from    lime 

and  orange  trees  in  Assam  and 

Coorg,    and    others   are   known 

from  fruit  trees,  coffee,  tea,  etc. 

^he     successful    treatment     of 

these  insects  consists  in    catch- 
ing the  large  beetles  when  this 

is  possible,  destroying  tlie  grubs 

in  their   burrows  by  means   of 

a  bent  wire,  or  by    means    of 

injecting  carbon   bisulphide,  kerosene  or  other  fluids  into  their  burrows, 

which  must  then  be  closed  up  with  Met  clay  or  tar. 


Fto.  liO. 

The  Anar  Bidterjly. 


I'OilEGKANATE    l'E«T«, 


179 


Fig.  200. 
Anar  Calerpillar.     {Magnijied  iifice.) 


The  Anar  Caterpillar.^ 

The  cultivator  o£  the  pomegi-anatc    [una/-)    is  familiar  willi   the   i'aet 

that    a     i)ruportioii     of     the 

fruit    is    destroyed    by    this 

pest ;   in   a   bad    season    the 

proportion   is  very  hig-h ;    in 

normal     seasons    small.     At 

the   time   of  the   blossoming- 

of  the  fruit  tree,   the   female 

butterfly     deposits    the    eggs 

sing-ly   on   the  flowers.     The 

caterpillar  hatches  and  bores  into  the  developing  fruit,   within  which 

it  lives.  The  food  con- 
sists of  the  hard  seeds  of 
the  fruit.  The  larva  is  of 
a  dark  colour,  with  short 
hairs  and  lighter  patches 
of  colour  j  the  hind  elid 
is  flattened  above,  form^ 
ing  a  shield  with  which 
the    caterpillar   is    said    to 

close  the  hole  it  makes  in  the  rind  of  the  fruit.     When  full  fed,  the 

caterpillar  comes  out  of 

the  fruit   and  webs   silk 

over  the  base  of  the  fruit 

and   some   part   of    the 

stalk  j  it  then  re-enters 

the   fruit   and   turns  to 

the  chrysalis.  Appar- 
ently the  webbing"   over 

the   stalk  is   to  prevent 

the   fruit    from   falling 

to    the     ground ;      the 

behaviour  of  the  cater- 
pillar     in    anticipating- 

this  is  an  extraordinary 

instance      of      instinct, 

which   almost    amounts 


Fig.  201. 
Avar  CafeiyiUar.     {Mafjnified  twice.) 


Fig.  202. 
T?ie  Anar  Caterpillar. 


(Enlarged.) 


^   05.   ViracJioUi  iivcratcs.     Fabr.     (Lycscnida-.) 


N  Z 


180 


PESTS    OF    KRUlT. 


Fig.  203. 

Pupa  of  Anar 

Btitterjly. 


to  "  reasoning/''     From  the  chrysalis  a  pretty  buttertly  emerges,  which 
is  found  commonly  in  the  cold  weather. 

Thoug-h  feeding  g*enerally  in  pomegranates,  the  larva  is  also 
recorded  from  guava,  loquat  and  wild  fruits.  It  is 
distinctly  a  pest  in  pomegranate  gardens  and  is  a  diffi- 
cult insect  to  check.  If  all  flowers  came  out  together, 
it  might  be  possible 
to  systematically  hunt 
the  butterflies  in  the 
garden  with  nets. 
Though  familiar  with 
the  caterpillars,  pome- 
granate cultivators  do 
not  know  the  butterfly  which  alone 

can  be  checked. 

Nothing      can 

save     a     fruit 

once     attacked 

and  only  tying 

the  flowers  up  in  bags  immediately  after  pollination 

could  protect  them  from 

the  butterfly.     On  the 

other       hand,        every 

attacked  fruit  should  be 

burnt,  simply  to  lessen 

the  increase  of  the  pest. 

This  would  not  save  the 

present  crop  but   would  ^^^  ^oe. 

diminish  the  pest  for  the  next  crop.  Anar  Butterfly. 


Fig.  204. 
Anar  Butterfly. 


Fig.  205. 

Anar  Butterfly,  from 

above,  in  restiny 

position. 


CHAPTER  XV. 

CATERPILLAR  PESTS. 

CATERPILLARS  are  the  young  of  butterflies  and  moths,  recognisable 
as  a  rule  by  their  sucker-feet.  Nearly  all  are  lierbivorous,  and  as  their 
rate  of  multiplication  may  under  favourable  circumstances  be  very  large, 
they  are  common  pests.  In  many  cases  the  species  that  attack  crops  one 
season  may  next  season  be  so  few  as  not  to  be  seen  and  other  species  may 
take  their  place ;  those  that  are  specific  pests  of  particular  crops  come  every 
season,  but  these  are  dealt  with  above.  It  is  impossible  to  say  that  a 
particular  species  attacks  a  particular  plant  in  very  many  cases,  as  they 
vary  much  from  year  to  year  and  may  come  out  only  at  long  intervals  into 
the  crops.  Fortunately  their  habits  are  on  the  whole  sufficiently  similar  to 
make  certain  general  remedies  suitable  for  all  the  caterpillars  of  a  group, 
whatever  their  species.  It  is  only  necessary  to  consider  their  habits  and  not 
treat  a  leaf-eating  caterpillar  in  the  same  manner  as  a  surface  caterpillar. 

Leaf-eating  Caterpillars. 

Almost  every  plant  that  is  cultivated  as  a  field  or  garden  crop  is  at 


V. 


t^' 


\l/' 


/  \  '■ 


Fig.  207. 
JjeaJ'-eaUng  Caierjiillar  common  in  ilie  plains  on  leak.     A  similar  species  aifacJcs  maize, 


183 


CATEEPILLAH   PESTS. 


some  time  infosted  with  caterpillars  which  eat  the  leaves.  This  is  the 
most  common  way  in  which  herbivorous  insects  feed;  a  very  large 
number  of  caterpillars  are  confined  only  to  wild  plants_,  whilst  a  smaller, 


Fig.  208. 
Hairy  leaf-ealinri  Caierpillar  and  Us  Fufa, 

thoug-h  still  large,  number  have  been  found  iTpon  ciUtivated  plants  in  the 
plains  of  India. 

In  most  cases  a  few  caterpillars  are  found  on  the  plant,  not  sufficient 
to  do  any  injury  and  often  doing  some 
ultimate  good  by  eifecting  a  simple  prun- 
ing and  manuring  which  stimulates  in- 
creased production  of  flowers  and  seed. 
If  the  caterpillars  increase  or  continue  to 
infest  the  plants  for  a  prolonged  period, 
they  cause  an  appreciable  or  total  loss  of 
the  crop. 

Caterpillars  of  this  kind  are  so  common 
that  they  are  often  neglected  until  they 
multiply  to  such  an  extent  as  to  do  serious 
injury;    they    cannot    then  be    checked   by 


Fig.  209.  v 
Moth  of  comiiwn  verjetable 

the   simple  measures  that  would  have  been     Caterpillar.    Wings  in  repose. 

„  ,  .  „     ,      ,    ,  .  ,   . .  (Maanified  three  times.) 

successful  II  adopted  m  good  time. 

Leaf -eating  caterpillars  destroy    the  tissue  of  the  leaves;  if  few   in 

number  they  eat  holes  in  the  leaves ;  these  holes  or  the  little  grains  of 


LEAF-RATTNG    CATE«PTLLA"RS. 


183 


Fig.  210. 

Moth  of  common  vegetalle'eating  CaterpiUar, 

{3Taf)nijied  three  times,) 


excrement  being  the  only  signs  of  their  proseneo.     Sneli  grains  of  excre- 
ment are  often  mistaken  for 

eggs,  though  caterpillars  arc 

unable  to  lay  eggs. 

The  life   history  of   those 

insects  is  simple  and  can  be 

easily     traced     in    captivity. 

As  a  rule  the  parent  moth  or 

butterfly     deposits     a     largo 

number  of  eggs  on  the  leaves 

of   the   plants,   often   on  the 

under-surface,    singly    or    in 

clusters,    but    usually   spread 

over  several   plants.     The   eggs   are  small  and  not  noticed  as  they  are 

difficult  to  see.  In  the  butterflies  and 
larger  moths  each  egg  is  rounded,  a  little 
flattened  at  the  base  and  apex,  adorned 
with  sculptured  lines  and  ribs.  In  the 
smaller  moths,  the  eggs  are  commonly 
flattened,  oval  in  outline  and  very 
inconspicuous.  The  eggs  hatch  in  a 
short  time,  usually  less  than  a  week, 
into  little  caterpillars  that  crawl  about 
on  the  plants  and  feed  first  upon  the 
epidermis  of  the  leaves, 
grown  larger  they  eat  holes  in  the  leaves  or  eat  in  from 
until    the    whole    leaf 


Fig.  211. 

Moth  of  common  leaf-eating  Cater 

■pillar  of  rice. 


"When 
the  edge 
devoured.  They  are  voracious,  a  large 
amount  of  plant  tissue  being  con- 
sumed which  is  only  very  slightly 
digested  and  passes  out  of  the  body 
as  a  little  round  grain  of  excre- 
ment. Actually  the  greater  part  of 
the  food  consumed  passes  through, 
little  more  than  the  juice  of  the  plant 
being  absorbed  by  the  alimentary 
canal. 

The  first  moult  takes  place  in  a 
few  days  after  hatching  and  succes- 
sive moults  occur  until  the  cater- 
pillar is  full   grown,     Few    of    snch 


Fig.  212. 

Tufa  and  moth  of  Caterpillar  that  eats 

lilies. 


184 


CATEEPILLAK    PESTS. 


caterpillars  grow  to  more  than  one  inch  long,  many  species  never 
exceeding  half  an  inch  in  leug'th.  When  the  body  is  not  hairy  but 
somewhat  transparent,  the  caterpillars  are  often  greenish  from  the  colour 
of  the  food  in  the  alimentary  canal ;  or  they  are  opaque  green,  brown,  or 
variously  striped  and  marked.  Many  are  hairy,  spiny  and  provided  with 
horns  and  excrescences. 

The  duration  of  larval  life  varies  with  the  different  species  :  some 
are  full  fed  in  a  week,  others  only  after  two  to  three  weeks  or  longer. 
From  two  to  three  weeks  is  the  most  general  length  of  the  larval  life. 
These  caterpillars  have  regular  daily  habits  which  must  be  considered 
in  the  adoption  of  remedies ;  many  feed  only  in  the  morning  and  even- 
ing, hiding  away  in  the  soil  during  the  middle  of  the  day ;  others  feed 
principally  at  night  or  are  to  be  found  on  the  plant  only  in  the  early 
morning  and  late  evening. 

If  food  is  plentiful  they  feed  regularly  and  voraciously  until  they  are 
full  grown,  when  they  turn  to  chrysalides.  Before  doing  this  thc}^ 
hide  away,  some  making  cocoons  on  the  plant  or  in  the  soil,  others  enter- 
ing the  soil  and  making  cells  there,  others  again  twisting  over  the  leaf 
and  thus  making  themselves  a  shelter.  Butterfly  caterpillars  hang  them- 
selves to  the  plant  or  bend  over  a  part  of  the  leaf. 


Fig.  213. 
A  Semi'looper  Caterpillar,  the  first  pair  of  sticlcer-feet  reduced. 


The  period  of  pupation  is  determined  by  climatic  conditions,  and 
may  be  short,  as  in  the  rains,  or  prolonged  through  the  cold  weather  and 
succeeding  dry  hot  months  until  the  next  rains.  Hibernation^  is  the 
rule,  and  whilst  some  emerge  as  moths  or  butterflies  at  the  close  of 
the  cold  weather,  the  majority  emerge  only  in  the  rains.  The  first  brood 
appearing  in  April  would  be  followed  perhaps  by  a  second  in  June,  a 
third  in  August  and  the  last  in  October ;    more  usually  there  would  be  a 


LEAF-EATING   CATERPILLARS.  186 

brood  in  July,  another  in  Scptembor  and  tlion  liil)ernation.  Sucli 
general  statements  can  only  be  accepted  very  cantiousl}^  as  the  habits 
vary  with  individual  species. 

It  is  not  possible  to  give  a  list  of  the  species  which  attack  indivi- 
dual crops  and  such  a  list  would  serve  no  useful  purpose.  A  detailed 
account  has  been  given  of  several  species  (pages  96,  159,  etc.).  Rice  is  the 
food  of  many  species,  which  are  also  grass  feeders;  the  large  area  under  rice 
usually  allows  for  a  large  number  of  such  caterpillars  being  widely  spread 
so  that  the  damage  is  distributed,  but  exceptionally  they  are  so  abundant 
as  to  cause  serious  injury.  Some  crops  are  apparently  not  attacked  by 
caterpillars,  such  as  the  various  yams  (Dioscorea  and  Colocasia),  and  the 
tapioca  {Mani/iot).  Leaf-eating  caterpillars  are  destructive  principally  in 
small  areas  of  irrigated  crops  or  in  patches  of  special  crops  not 
generally  grown  in  the  district.  The  fields  of  mixed  crops,  grown  to 
a  limited  extent  in  April,  May  and  June,  usually  with  well  irrigation, 
suffer  heavily  from  this  pest,  as  many  moths  emerge  from  hibernation 
at  this  time  and  lay  eggs  on  a  small  area  of  crop.  Later  in  the  year 
the  same  caterpillars  may  be  spread  over  a  far  larger  area  of  staple  crops 
with  no  appreciable  harm.  The  same  may  be  said  of  special  crops  of 
which  only  a  small  area  is  grown ;  this  applies  particularly  to  experi- 
mental farms  and  is  one  of  the  reasons  why  crops  grown  on  experimental 
farms  suffer  to  so  large  an  extent  from  insect  pests. 

In  general,  each  species  of  caterpillar  feeds  only  on  a  few  closely 
related  plants  ;  thus  there  are  species  which  feed  only  on  cotton,  bhindi, 
ambadi  [Hibiscus  caoinalitius)  and  hibiscus,  others  on  maize  and  sorghum 
or  on  cabbage,  rape  and  mustard.  A  small  number  have  a  greater 
range  of  food-plants,  such  as  the  omnivorous  Gram  Caterpillar  (page  144) 
which  eats  gram,  opium,  tobacco,  tipari,  tomato,  maize,  etc.  It  may 
be  remembered  that  the  caterpillars  have  no  choice  of  food-plant  in 
most  cases,  since  they  can  move  over  only  short  distances,  but  the  moths 
seek  out  the  right  plant  on  which  to  lay  their  eggs,  their  instinct 
telling  them  on  which  plants  their  young  will  be  able  to  feed.  If  no 
plants  are  found  the  moths  can  live  for  a  considerable  period  before 
laying  eggs. 

Treatment. — There  are  several  simple  methods  of  checking  leaf- 
eating  caterpillars  and  of  preventing  them  from  becoming  serious 
pests.  The  simplest  method  is  to  pick  them  off  by  hand ;  it  is  of  course 
useless  then  to  liberate  them  near  the  field  from  which  they  were  taken 
as  the  cultivator  sometimes  does,  but  they  must  be  destroyed.  In  most 
cases  the  destruction  of  the  first  brood  prevents  the  injury  caused  by  the 
otherwise  large  second  brood ;  unfortunately  the  first  brood  commonly 


186  CATEIIPILI.AII   PESTS, 

escapes   notice   as  it  is  a  small  one  and  the   large   second  brood  is  so 
abnndant  that  hand-picking-  becomes  a  difficult  business. 

In  some  instances  it  is  possible  to  shake  the  caterpillars  to  the  ground 
and  crush  them.  When  the  caterpillars  hide  in  the  ground  by  day -light, 
cultivation  between  the  plants  exposes  them  to  birds  and  kills  many. 
The  same  is  true  when  they  have  entered  the  ground  and  become  chry- 
salides. This  is  always  necessary  when  the  field  is  badly  attacked,  as 
a  large  number  of  chrysalides  will  probably  be  found  there. 

On  low  crops  the  use  of  the  bag  (page  72)  is  advisable,  large  numbers 
being  swept  up.  As  a  preventive  measure  one  must  do  everything 
possible  to  stimulate  the  rapid  and  healthy  growth  of  the  plant ;  a  strong 
vigorous  plant  that  is  putting  out  many  leaves  can  stand  far  more  than 
a  weak  unhealthy  one. 

The  practice  of  sowing  mixed  crops  has  an  influence  on  leaf-eating 
caterpillars  and  the  mixtures  sown  especially  on  small  irrigated  areas  in 
the  dry  hot  weather  are  almost  necessary  if  the  main  crop  is  to  be  estab- 
lished. The  caterpillars  which  are  very  prevalent  in  these  crops,  attack 
a  subsidiary  crop  which  can  be  rooted  out,  leaving  the  main  crop  well 
established  and  healthy.  Occasionally  it  is  possible  to  use  another  crop  as 
a  trap  for  caterpillars,  which  then  do  not  injure  the  main  crop.  Thus 
sorghum  and  maize  are  valuable  in  certain  areas  in  cane  fields  and  the 
value  of  bhindi  as  a  trap  for  pests  of  cotton  is  being  tested.  Such  plants 
must  be  used  with  caution.  If  allowed  to  grow  too  long  they  first 
attract  pests  from  outside  and  then  transmit  them  to  the  main  crop, 
becoming  breeding  places  for  imdesirable  insects  which  when  abundant 
leave  them.  The  essence  of  a  trap  crop  is  to  destroy  it  with  the  insects 
on  it  at  the'  right  moment.  Birds  are  extremely  valuable  as  checks  on 
leaf-eating  caterpillars  and  anything  which  encourages  such  caterpillar- 
eating  birds  as  mynas  is  useful.  The  growing  of  roadside  trees  has  a 
very  special  value  in  this  connection,  especially  when  these  trees  are  such 
as  mynas  frequent,  and  the  cultivator's  practice  of  putting  branches  of 
trees  in  an  infested  field  of  paddy  so  that  the  insect-hunting  birds 
may  come  and  perch  there  is  a  shrewd  one.  The  common  hen  is 
a  valuable  ally  in  gardens  and  small  cultivation,  but  she  requires 
some  food  besides  caterpillars  and  must  not  be  left  to  feed  exclusively 
upon  them. 

In  most  cases  one  of  the  above  precautions  can  be  applied  success- 
fully and  when  all  else  fails,  an  application  of  insecticide  can  be  resorted 
to  if  the  crop  is  worth  it.  For  small  areas  of  vegetable  crop  and  for  small 
irrigated  patches,  the  tin  sprayer  and  a  dose  of  kerosene  emulsion  does 
{ill  that  is  required ;  if  the  caterpillars  are  large,  lead   arseniate  may  be 


DESTROYING  CATEBPILI^ARS, 


187 


advisable,  either  sprayed  or  dusted  on.     In  some  oases  a  mixture  of  dry 

dust  and  kerosene  or  dry  dust  (or  lime)  and  sanitary  flnid  ean  be  applied 

to  the  plants ;  this  acts  with  plants  like  cabbage,  maize,  sorghum,  etc.,  whose 

leaves  are  so  formed  as  to   hold 

the   powder.     Every    attack    of 

leaf-eating    caterpillars    can    be 

so    checked,    but    the  cultivator 

will  not   always  think  the  crop 

is    worth    the    cost  of    the  iu- 

seeticide    or     the    labour.      The 

application    of    insecticides     by 

means   of  tin   sprayers   is  more 

readily      adopted     by     market 

gardeners   who  grow  vegetables 

for   sale  in  the  towns,  than  by 


Fig.  214 
Typical  Swarming  Caterpillar. 


cultivators ;  every  cabbage  that  is  eaten  by  caterpillars  means  a  loss  to  the 
market  gardener. 

At  present  over  thirty  species  of  leaf  caterpillars  are  known  which 
attack  crops.  Many  more  species  will  be  found,  but  all  have  essentially  the 
same  habits  and  life  history. 

The  question  of  parasites  is  a  very  important  one  in  connection  with 
leaf -eating  caterpillars.  As  a  rule  when  these  caterpillars  become  very 
abundant,  the  parasites  also  increase  to  such  an  extent  as  to  kill  a  very 
large  percentage  of  the  pupse.  The  result  is  that  few  moths  hatch  and 
the  pest  does  not  reappear  as  it  otherwise  would.  This  is  discussed  in  a 
later  section  (page  368). 


Swarming  Caterpillars. 

It  is  not  unusual  to  find  that  large  numbers  of  caterpillars  come  out 
suddenly  in  the  fields,  ravage  the  crops  and  disappear.     The  caterpillars 

are  large,  smooth,  not  hairy,  coloured 
in  green  or  brown  usually  with  stripes 
along  the  body  from  head  to  tail.  They 
appear  in  large  numbers,  eat  a  variety 
of  crops,  and  disappear. 

This  form  of  pest  is  very  similar  to 
the  last  but  is  distinct  in  that  the  cater- 
pillars really  appear  in  swarms,  and 
damage  large  areas  of  crops.  The  methods  of  treating  such  an  attack  are 
not  the  same  as  those  used  against  the  ordinary  leaf -eating  caterpillars, 


Fig.  215. 
Moth  of  Swarming  Caterpillar, 


188  CATERPILLAR  PESTS. 

In  every  case  of  swarming-  caterpillars,  the  following'  is  the 
sequence  of  events  that  occurs.  Under  favourable  circumstances  a  lai'ge 
number  of  moths  hatch  at  a  particular  time ;  very  many  emerge 
from  the  chrysalides  simultaneously  and  may  be  seen  flying  about 
in  the  evening.  These  moths  lay  eggs;  every  female  moth  lays  at 
least  a  hundred  and  some  lay  as  many  as  one  thousand;  if  circum- 
stances are  favourable  they  all  lay  eggs  within  a  few  days.  After 
a  week  or  so,  the  eggs  hatch  out  and  multitudes  of  caterpillars  appear. 
They  are  very  tiny  at  first  and  feed  steadily ;  if  plentiful  they  devour 
the  plant  they  hatch  on,  becoming  perhaps  half  grown;  they  then 
commence  to  search  for  food  and  wander  about;  if  large  numbers  are 
hatched  out,  they  then  form  into  masses  and  if  they  find  a  crop  they 
will  absolutely  destroy  it. 

Wlien  they  have  become  full  fed  they  descend  into  the  ground 
and  become  chrysalides,  forming  for  themselves  earthen  cases  in  the 
ground.     All  will  perhaps  disappear  in  a  few  days  and  the  reports  say 

that  they  have  died;  but 
should  circumstances  be 
favourable  these  chrysalides 
will  yield  moths  which  will 
again  lay  eggs,  giving  rise 
to  a  fresh  attack. 

Such       is       the       usual 
sequence;  since  the  cultivator 
only     sees     the    caterpillars 
feeding,  he  does  not  under- 
^^'^-  ^^^-  stand    the    cause,   nor  does 

Moth  of  a  common  Sivarminq  Caierpillar.  ,  ,        ,  ii  i-\ 

he  connect  together  the 
appearance  of  moths  and  the  subsequent  swarms  of  catei'pillars.  These 
attacks  are  worst  when  the  conditions  are  such  that  the  moths  all 
emerge  from  the  chrysalides  together.  At  the  end  of  the  cold  weather 
it  becomes  warm  perhaps  within  a  very  few  days ;  then  a  vast  number 
of  moths  hatch  out  together;  should  the  cold  weather  end  early  the 
caterpillars  attack  the  rabi  crops,  and  the  destruction  may  be  very  large ; 
if  the  cold  weather  continues  later  the  caterpillars  may  not  find  crops 
to  eat ;  if  it  comes  very  gradually,  the  moths  do  not  all  hatch  out  at 
once  and  the  caterpillars  do  not  come  in  swarms.  If  the  catei*pill^s  do 
not  come  in  swarms  the  wild  plants  may  be  sufficient  for  their  food 
and  the  crop  will  possibly  not  be  attacked.  Swarming  caterpillars  are 
worst  when  they  are  so  abundant  at  one  time  that  they  exhaust  their 
^'ild  food-plants  and  are  compelled  to  enter  the  crops  to  find  food, 


CATEiPILtiAtt    S^ARJiS. 


189 


These  caterpillars  do  not  occur  throughout  India ;  they  are  serious 
pests  only  when  the  conditions  are  favourable  and  such  conditions  arc 
not  universal  in  the  plains  of  India.  The  climatic  conditions  of  Eehar 
and  the  United  Provinces  seem  to  be  particularly  favourable  to  them, 
possibly  because  the  cold  weather  suddenly  gives  place  to  the  warm 
weather  when  the  moths  hatch  out  in  abundance.  Little  is  yet  known 
of  the  occurrence  of  such  swarms  of  caterpillars  but  they  are  likely  to 
occur  wherever  the  conditions  favour  them. 

A  curious  feature  of  these  caterpillar  swarms  is  the  number  of  species 
that  are  found  composing  them.  Apparently  the  favourable  conditions 
that  produce  a  large  number  of  one  species  favour  others  and  we  find 
several  species,  one  in  great  numbers,  others  in  smaller  but  still,  in  the 
ao'o-reo'ate.  laro-e  numbers.  For  this  reason  also,  it  is  impossible  to  rely 
upon  the  reports  and  specimens  sent  in,  and  as  only  a  few  cases  have  been 
investigated,  little  is  known  of  the  species  which  occur  in  this  way.  The 
basis  of  a  swarm  is  nearly  always  a  caterpillar  of  the  kind  known  as  an 
"  Army  Worm,^"*  that  is  a  smooth-striped  caterpillar  (fig.  214),  which 
emerges  into  one  of  perhaps  six  moths  ^  of  the  type  figured.  With 
them  are  for  instance  the  Tobacco  Caterpillar  (fig.  176),  the  Sorghum 
Caterpillar  (fig.  156),  the  Gram  Caterpillar  (fig.  162),  several  butterfly 
and  many  other  moth  caterpillars  which  are  typically  leaf -eating- 
caterpillars. 

As  these  pests  occur  suddenly  and  not  regularly,  little  has  been  done 
to  check  them  or  to  test  the  best  means  of  destroying  them.  The  usual 
methods  of  applying  lead  arseniate  would  be  the  best  if  generally  avail- 
able ;  this  shoidd  be  done  on  experimental  farms.  Other  methods  depend 
upon  the  local  conditions.  The  great  thing  is  to  do  something  quickly ; 
the  cultivator  does  nothing,  because  he  thinks  that  caterpillars  are  sent 
as  a  punishment  or  at  least  have  a  miraculous  origin. 

When  the  crops  are  young  or  low  the  usual  hopper  bag  can  be  used  to 
sweep  up  the  caterpillars  (see  page  72);  discretion  must  be  used  in  doing 
this  only  when  the  caterpillars  are  out  feeding.  When  this  is  not  possible, 
an  application  of  lime  and  kerosene,  road  dust  and  kerosene  or  other  offensive 
powders  may  be  of  use.  When  the  caterpillars  are  concentrated  in  a 
small  area,  it  may  be  possible  to  trench  all  round  to  isolate  them,  then 
apply  a  mixture  or  a  spray  or  worry  them  with  a  hopper  bag  tiU  they 
become  restless  and  move,  when  they  will  fall  into  the  trenches  where 
they  may  be  killed. 


''237.  Agrotis  fiainmatra.     Schiff.     (Noctuidse.) 
238.  Euxoa  segeiis.     Schiff. 
235.  S'podofiera  mauritia,     Boisd, 


239.  Euxoa  spinifera.     Hubu.  \ 

240.  Agrotis  ypsilon.     Roth. 
110.  Caradrina  exigua,     Gueii. 


l9d  cAterpillak  pests'. 

Trenching-  is  one  excellent  method  o!  isolating  them,  and  so  long-  a^ 
the  trench  has  sloping-  sides,  it  need  not  be  more  than  eight  or  ten  inches 
deep.  The  cultivator  naturally  hopes  the  caterpillars  will  g-o  into  his 
neighbour's  plot  of  land  and  does  not  trench  to  isolate  them  on  his  plot ; 
his  neighbours  should  trench  to  protect  their  own  fields.  Methods  of 
surface  cultivation  are  useful  when  the  caterpillars  bmy  themselves  by 
dayj  light  surface  cultivation  turns  them  out  where  the  birds  will  eat 
them.  So  also  when  the  caterpillars  disappear;  probably  they  have 
gone  into  the  soil  to  pupate.  Surface  cultivation  turns  them  out  for  the 
birds  to  kill  them. 

The  principal  reason  why  nothing  is  done  to  check  these  pests  is  that 
they  invariably  disappear  after  a  time  (to  pupate  and  come  again  as 
moths).  The  cultivator  hopes  they  will  do  no  harm  and  sooner  or  later 
sees  them  vanish ;  he  attributes  this  to  invocations  of  holy  men  or  to 
fate,  but  does  not  realise  that  they  will  come  again  and  are  not  dead  but 
undergoing  metamorphosis ;  should  circumstances  be  favourable,  the 
increase  of  the  emerging  moths  will  be  enormous. 

These  pests  come  from  jungles  and  waste  lands  ;  the  planting  of 
waste  lands ;  strips  bounding  on  fields,  boundary  strips,  etc.,  with  good 
grass  would  do  much  to  check  them  ;  trees  are  not  liable  to  bring  them 
but  flowering  plants  and  low  vegetation  encourage  them.  The  ideal 
cultivated  areas  would  include  no  waste  lands  wath  scrub  where  such 
vegetation  is  growing,  but  only  grass  land  and  trees. 

Finally,  the  most  important  thing  is  to  worry  the  caterpillars  and 
prevent  them  feeding.  The  bag,  a  rope,  a  latlti,  almost  anything  dragged 
through  an  infested  crop  disturbs  them.  In  a  plague  of  swarming 
caterpillars  recently  investigated,  it  was  found  that  sweeping  the  crop 
with  a  heavy  lathi  was  sufficient  to  disturb  the  caterpillars  so  much  that 
they  stopped  feeding.  It  was  only  necessary  to  do  this  twice  a  day  and 
the  crops  were  practically  uninjured.^  If  it  were  possible  to  induce  the 
cultivator  to  do  anything  energetically,  no  matter  how  simple,  such 
plagues  could  be  rendered  almost  harmless. 

Surface  Caterpillars. 

Caterpillars,  which  hide  by  day  in  the  soil  and  come  out  at  night  to 
eat  vegetation  or  to  cut  off  young  plants,  are  commonly  known  by  the 
above  name,  or  in  America  as  "  cut^worms."  They  are  large,  smooth 
caterpillars  coloured  in  dirty  browhj  green  or  neutral  tiiitsj  with  obscure 
longitiiditlal  liiies^  or  in  some   c&ses  with  black  spots.     "When  handled 

1  Report  of  C.  S.  Miora  aud  D.  N.  Pal. 


SUEt'ACE   CATERPltLAHS.  l9l 

tliey  curl  up,  not  as  a  cockchafer  g-rub  docs  with  the  ventral  surface 
inwards,  but  to  one  side. 

These  caterpillars  are  universal  and  some  species  arc  of  almost  world- 
wide distribution.  It  is  scarcely  known  how  many  species  behave  in  this 
way  in  India ;  though  several  common  species  have  been  reared,  it  is  exceed- 
ingly difficult  to  determine  accurately  how  much  damage  they  do,  and 
in  recent  years  only  one  species  ^  seems  to  have  been  common  or  abundant. 

This  is  the  so-called  "  Greasy  Cut-Worm,''  and  its  life  history  may  be 
taken  as  typical  of  the  group. 

The  moth  lays  a  very  large  number  of  small  white  eggs  singly,  on 
weeds  or  stones,  in  any  convenient  situation  near  the  ground  in  waste 
lands,  in  grass  borders,  near  fields  or  in  weedy  fields.  The  caterpillars 
feed  on  plants  and  live  by  day  in  hiding,  coming  out  at  night  to  feed. 
When  half  grown  they  have  a  habit  of  biting  through  the  base  of  the 
plant,  if  it  is  a  small  one,  thus  cutting  it  off ;  the  plant  is  then  removed 
to  the  burrow  in  the  soil  where  the  caterpillar  finds  shelter.  Night  after 
night  the  caterpillar  lives  thus,  until  it  becomes  over  an  inch  long,  and  is 
large  enough  to  destroy  half -grown  opium  plants.  Each  caterpillar  cuts 
off  more  than  it  can  eat  and  the  destruction  caused  is  very  large.  When 
full  grown  the  caterpillar  makes  a  cell  in  the  ground  pupating  there.  The 
moth  emerges  after  a  varying  interval,  and  there  is  reason  to  believe  that 
though  the  caterpillar  remains  active  through  the  winter  in  most  parts 
of  the  plants,  the  pupa  hibernates  in  moderate  cold. 

Surface  caterpillars  feed  principally  upon  weeds,  in  waste  lauds  or 
unweeded  fields.  They  are  often  abundant,  not  in  the  crops,  but  in  weedy 
places  where  there  is  good  growth  of  low  vegetation.  They  attack  crops 
principally  after  floods ;  the  exact  explanation  of  this  fact  is  not  under* 
stood,  but  it  appears  to  be  generally  true  that,  when  land  has  been 
flooded,  cut-worms  are  found  on  it  in  the  ensuing  rahi  season,  and  that 
after  extensive  floods,  surface  caterpillars  are  most  abundant  in  fields  and 
gardens.  The  number  of  surface  caterpillars  may  also  be  influenced  by 
the  character  of  the  season,  damp  weather  being  favourable  to  the  emer- 
gence of  moths  and  consequent  rapid  breeding.  Surface  caterpillars  are 
found  most  abundantly  on  young  raU  crops  and  throughout  the  cold 
weather.  They  attack  a  great  variety  of  crops,  including  opiunij  tobacco, 
gram,  peas,  lucerne. 

Surface  caterpillars  are  not  generally  distinguished  from  leaf-eating 
caterpillars  which  never  live  on  the  surface  or  from  the  swarms  of  the 
caterpillars  which  come   in  Marcli^  April  and  May.     Yet  these  surface 

*  240/    Agrotis  yp&itoit.     llott    (Ifoctuiclic.) 


192 


CATERPILLAR  PESTS. 


caterpillars  need  quite  distinct  treatment  and  cannot  be  checked  by  the 
same  methods  as  other  caterpillars. 

The  principal  precaution  against  them  lies  in  clean  cultiva- 
tion, which  includes  putting  all  waste  lands,  boundary  strips,  etc., 
in  good  grass;  large  areas  of  weeds  and  low  vegetation  promote 
cut-worms,  affording  a  breeding  place  from  which  the  caterpillars  or 
moths  come. 

When  the  caterpillars  attack  a  crop,  heaps  of  any  green  vegetation 
should  be  placed  in  the  field  to  attract  them.  This  is  not  only  neces- 
sary to  supply  them  with  some  other  food  than  the  delicate  young  plants, 
but  large  numbers  will  be  trapped  in  this  way  and  can  be  collected  daily 
and  put  into  water. 

The  use  of  poisoned  baits  of  bran  or  bhusa  and  arseniate  is  a  remedy  in 

use  elsewhere;  it  mil  prob- 
ably be  found  suitable  and 
has  given  good  results  on  an 
experimental  scale  of  5  acres 
(see  page  287). 

When  the  cultivators  are 
familiar  with  the  habits  of 
the  pest,  they  are  able  to 
destroy  it  by  searching  daily 
for  the  holes  of  the  cater- 
pillars, betrayed  by  the 
green  leaves  of  the  food 
taken  in  the  night  to  the 
burrow.  This  is  the  sim- 
plest remedy  and  one  that, 
energetically  applied,  averts 
a  great  loss  in  opium  and 
tobacco  crops. 


Fig.  217. 
Sairy  Caterpillar  of  Behar. 


When  possible,  irrigation  brings  up  the  caterpillars  and  in  bad  cases 
would  clear  the  field ;  simply  flooding'  the  field  once  is  suflicient  to  bring 
up  all  the  caterpillars  in  the  soil  when  they  may  be  destroyed  or  they  may 
be  left  to  the  mynas  to  eat.  It  is  stated  that  the  caterpillars,  when  on 
their  nightly  prowls  in  search  of  plants,  can  be  trapped  in  smooth  holes 
made  in  the  soil  with  a  pointed  stick ;  the  stick  is  rotated  till  a  n«?at  hole 
with  smooth  sides  is  produced ;  a  caterpillar  falling  in  cannot  get  out  and 
is  kiUed  next  day. 

The  outbreaks  of  surface  caterpillars  which  take  place  after  the  cold 
weather  are  preceded  by  the  emergence  of  the  moths,  a  phenomenon  at 


IIATHY    CATEIJPII.LAES. 


193 


once    recognised    by 


Fifi.  218. 
Mofh  of  Bell  a  r  Hair  if  Caterpilla 


anyone  familiar  with  the  moths ;  the  moths 
come  to  light  and  are  found  in 
houses  at  night.  The  species^ 
fig'ured  (fig-.  216)  comes  out  in  vast 
numbers  in  February  or  March, 
flying-  in  the  dusk;  other  species 
do  the  same,  and  an  observer  fami- 
liar with  the  moths  will  recognise 
them  and  expect  a  later  attack  of 
caterpillars. 


Hairy  Caterpillars. 

In  many  parts  of  India,  large  numbers  of  hairy  caterpillars  appear 
at  certain  seasons  and  either  destroy  special 
crops  or  move  from  field  to  field  attacking- 
almost  any  crop.  These  pests  appear  when 
conditions  are  favourable  to  the  emergence  of 
large  numbers  of  the  parent  moths  which 
lay  eggs  on  crops  or  on  wild  plants;  if  the 
eggs  are  abundant,  the  caterpillars  ravage  the 
crops  or,  after  eating  their  wild  food-plants, 
move  into  crops  and  devour  them. 

Apparently  particular  species  are  destruc- 
tive in  distinct  areas ;  the  hairy  caterpillars  of 
Guzerat  are  distinct  from  those  of  Behar  and 
Oudh,  and  from  those  found  in  Madras.     Their  17.010 

r  IG.  ZIy. 

time  of  appearance  varies  with  climatic    con-      Moth  of  Behar  KairyCaie,- 
ditions,  but  is  largely  confined  to  the  rains.     In  piUar. 

Guzerat,  they  appear 
chiefly  in  the  early 
weeks  of  the  rains; 
the  moths  hatch  out 
in  abundance  with 
the  first  rains,  lay 
eggs,  and  the  cater- 
pillars hatch  and  feed 
on  the  youug  crops. 
In  Fehar,  one  brood  succeeds  another  from  the  end  of  the  cold  weather, 
and  this  will  occur  when  the  conditions  are  favourable.     The  life  histoiy 

^Affroiis  fammatra.     (Noctuidse.) 


Fig.  220. 
Jtde  Hairy  Caterpillar.     {Magnified  tn-ice) 


194 


CATERPILLAR   PESTS. 


of  these  caterpillars  is  similar  to  that  of  the  preceding-  caterpillars.     The 
moths  lay  eggs  in  cliistors  ou  their  food-plants^  the  eggs  hatching  in  a  few 


Fig.  221, 
Moth  of  Jute  Sairy  Caterpillar.     (Majnijled  twice.) 

days  as  a  rule.  The  caterpillars  feed  for  two  to  four  weeks  and  become 
chrysalides  in  a  cocoon  in  the  ground  or  hidden  away  under  stones,  etc, ; 
the  moth  emerges  in  five  to  ten  days  and  again  lays  eggs.  The  whole 
period  from  egg  to  egg  is  four  to  six  weeks,  so  that  several  broods  succeed 
one  another  so  long  as  conditions  are  favourable. 

The  caterpillars  are  very  characteristic  in  appearance ;  they  are  long, 
usually  of  a  black  and  yellow  colour,  with  hairs  covering  the  whole  bodj'. 
When  the  caterpillar  pupates,  the  hairs  are  used  with  the  silk  to  prepare 

the  cocoon. 

The  moths  are  distinct 

in     appearance     from    the 

moths    of    other    injurious 

caterpillars ;       most       are 

brightly       coloured,       red, 

orange  or  white  with  black 

markings,  or  dots. 

Less  than  ten  species* 

seem    to    be    common    in 

different    parts    of    India, 

attacking     a     variety     of 


Fig.  222, 
Moth  of  Gujarat  Sairy  Caterpillar. 


*  There  are  four  principal  species  in  India- 
233.  Amsacta  moorei.     W.    Madras. 
231,  Amsacta  lineola.  F, 
220.  Amsacta  lactinea.  Cr. 
J3C.  Diacrisia  olliqna.     Wlk-     Behar  and  Oudh. 


>  Gujarat. 


HAIRY   CATEIIPILLATIS. 


195 


^^ 

:^ 

^ 

'   '  \  y  ' 

<* 

'""i'.«i\a.a!'' 

Fig.  223. 
Orange  Sann  Moth. 


plants.  Groundnut  and  sann  hemp  are  the  usual  food-plants,  but  when 
the  caterpillars  are  abundant^  they  will  attack  indigo,  castor,  til,  cotton, 
jute,  tobacco  and  other  crops.     The  methods  of  treatment  are  similar  to 

those  used  against  the  usual  leaf-eat- 
ing- caterpillars.  In  case  of  a  small 
attack  the  brightly  coloured  cater- 
pillars can  be  readily  seen  and  picked 
off.  This  is  of  great  importance  in 
the  case  of  the  first  brood,  as  by  des- 
troying that  much  subsequent  loss 
may  be  saved. 

As  the  caterpillars  become  chrys- 
alides near  the  surface  of  the  ground, 
light  cultivation  does  good,  if  carried 
out  when  the  caterpillars  disappear 
from  the  plants.  In  tliis  and  in 
other  cases  of  caterpillar  attacks, 
much  depends  upon  what  weeds  are 
growing-  near  the  fields;  if  certain 
leg-nminous  weeds  grow  in  the  jungle  or  in  the  waste  lands  near  the 
fields,  the  moths  are  likely  to  be  present  and  to  lay  eggs  on  them ;  should 
the  caterpillars  be  abundant,  they  will  enter  the  crops  after  eating-  the 
weeds  (see  also  page  192). 

The  radical  treatment  is,  as  in  other  cases,  to  apply  a  poison  such 
as  lead  arseniate,  dusting  or  spraying-  it  on  the  plants  in  powder  mixed 
with  lime  or  dust.  As  these  caterpillars  occur  chiefly  upon  field  crops, 
this  method  is  as  yet  beyond 
the  reach  of  the  cultivator. 
It  is  far  better  to  anticipate 
the  caterpillars  and  collect  them 
on  their  wild  food-plants  before 
they  attack  the  crops;  they 
appear  as  a  rule  only  at  definite 
times,  and  a  search  through  any  lands  growing  weeds  will  probably 
reveal  them  and  show  what  their  wild  food-plants  are.  The  caterpillars 
must  then  be  collected  and  destroyed ;  in  places  where  such  caterpillars 
come  often,  a  watch  should  be  kept  particularly  for  the  first  brood  which 
must  be  destroyed  on  its  wild  food-plants  before  it  attacks  the  crops. 


Fig.  224. 
Hairy  C aterpillar  from  Sann  Hemp. 


O  % 


CHAPTER  XVI. 


BEETLE     PESTS. 

BEETLES  form  the  largest  and  most  varied  group  of  insects  including 
many  distinctive  species.  As  they  live  concealed,  their  larvae  are 
so  seldom  found  that  far  less  is  known  of  them  than,  for  instance,  of 
caterpillars.  They  are  also  far  more  difficult  to  distinguish  specifically. 
It  is,  therefore,  necessary  to  discu^ss  groups  rather  than  individual 
species.  Increased  knowledge  will  show  that  beetles  are  far  more 
destructive  than  is  generally  known;  especially  will  this  be  so  in  the 
"  weevils "  whose  larvae  are  almost  wholly  herbivorous  but  live  lives  of 
such  concealment  that  we  are  still  ignorant  of  the  life  histories  of  our 
commonest  species.  Beetle  grubs  are  notoriously  hard  to  rear  and 
cannot  be  identified  until  they  are  reared.  Any  observer  who  is  so 
fortunate  as  to  rear  one  should  put  the  facts  on  record,  for  such  inquiry 
is  most  needed. 

Cockchafer  Beetles. 


These  beetles  appear  in  larg 


Fig.  225. 
Coclcchafer  Beetle. 

brown  head,  a  much  wrinkled 


e  numbers  at  regular  seasons  of  the  year, 
flying  by  night  and  feeding  upon 
leaves.  They  are  round,  thickset 
insects,  usually  hard,  not  more  than 
half  an  inch  long,  and  most  easily 
recognised  by  the  peculiar  knol)  at  the 
end  of  the  antennae  (see  fig.  335). 
Their  colour  is  generally  brown,  black 
or  some  sombre  tint,  but  some  are 
very  bright  metallic  green,  others  a 
vivid  red  brown  with  white  spots.  All 
have  the  same  build,  the  same  antennae 
and  the  same  heavy  droning  flight. 

Cockchafers  are  not  often  reported 
as  injurious  insects,  but  do  far  more 
harm  than  is  generally  known.  They 
are  destructive  at  two  periods  in 
their  life — below  ground  as  the  larva, 
above  ground  as  the  imago.  The 
larva    is    a    white    grub,    with    large 

white  body  curved  in  a  half  circle  and 


COCkCHAFERS. 


19} 


tlirec  pairs  of  logs.     It  may  be  found  almost  anywhere  by  digging-  in 

the  soil,  and  tlie  larger  specimens  have  a  peculiarly  large  terminal  seg- 
ment of  a  livid   grey   colour.     This 

grub     lives     among     the    roots    of 

plants,    a    few    inches     beloAV     Ihe 

surface   of    the    soil.      Its    food    is 

probably  entirely  vegetable,  con- 
sisting of  the  roots  of  grasses  and 

other     plants;     hot      dry      Aveather 

sends  the  grubs  down  further  from 

the     surface,     wet    weather    brings 

them  up.     The  life  occupies  several 

months,    probably   nearly  nine ;    the 

full-fed      grub      makes     a     smooth 

earthen    case,    curls    up    inside    and 

transforms    to    the     pupa.      Nearly 

a   year    after    the    parent    laid    the 

eggs,  the  beetle  comes  out,  pushing 

open  the  mud  case,  forcing  its   way 

up  through  the    soil  till  it   emerges 

to    the    light.      It   distends   the    air 

sacs   in    the    body    and    flies    away. 

Each    species    emerges    annually    at 

the  proper  season    depending    upon    the   climate,  so   that  we  find  large 

numbers   of   a    species    coming    out    about    the    same   time.      They    lie 

hidden  in  the  day  and  in  the 
evening  fly  out,  to  seek  a  suit- 
able plant  on  which  to  feed.  On 
such  plants  they  gather  in  num- 
bers, eating  the  tissue  of  the 
leaves  till  the  whole  plant  is 
stripped,  only  the  skeleton  of  the 
leaf     being     left.      The     beetles 


Fig.  226. 

Cocl-chafer  Beetle. 

Larva  on  the  left.     Fupa  on  ihe  right. 


AV^\V;\/)//f 


~  ""  ^    Vv 


5S.0 


\T- 


'r  ^ 


'^^yh-' 


^"^^'^''^ 


mate,  and  lay  eggs  in  the  soil, 
after  whicli  they  die.  The  whole 
period  may  occupy  one  year  or 
more  and  probably  one  or  two 
years  are  required  by  most  Indian 
species. 

Damage  is  done  by  the  larvte  to  the  roots  of  plants,  especially  in  very  wet 
weather  when  the  grubs  come  up  near  the  surface.     Crops  are  occasionally 


Fio.  227. 
Coclchafer  larra.     {Tirice  maf/nified.) 


198 


SEETtE  PESI^S. 


attacked,  bajra  [Pennisetum  typlioideum)  and  other  millets  especially; 
there  are  also  many  cases  o£  injury  to  garden  plants 
and  veg-etable  crops,  the  grubs  living  for  choice  in 
highly  manured  soil.  Nurseries  and  especially  man- 
ured plots  are  usually  full  of  the  grubs,  which  may 
hatch  from  eggs  laid  there  by  the  beetles,  or  may  be 
put  in  with  the  manure  if  fai-myard  manure  is  used. 

These  grubs  are  difficult  to  destroy ;  where  it  is 
possible,  cultivation  turns  them  out  when  birds  then 
eat  them  readily ;  flooding  brings  them  up  nearer  the 
surface  where  they  can  be  more  readily  turned  out,  but 

never  actually  kills  them  or 

exposes       them.       In      hot 

weather,       anything      that 

tends  to  dry  and   heat  the 


Fig.  228. 
Cochcliafer  larva. 

surface  soil  drives  the  grubs  down  below  the 
surface  roots.  Artificial  manure  such  as  kainit, 
saltpetre,  etc.,  can  sometimes  be  used  sparingly  to 
drive  them  down  and  a  dressing  of  soot  has  much 
the  same  effect.  This  is  the  only  thing  possible 
when  grass  lawns  are  affected,  though  a  liberal 
watering  with  soapy  water  may  do  good. 
The  beetles  destroy  plants  in  a  more  evident  manner,  coming  out 
at  night  in  large  numbers  and  stripping  the  plants.     This  is  somewhat 


Fig.  229. 
Cockcli  afer  larva,  fo  u  nd 
the  soil. 


Fig.  230. 
Cockchafer  Beetles  citing  a  leaf. 


COCKCUAFEllS. 


199 


rare  in  tlic  plains  bnt  more  common  in  the  hills,  where  the  hcetlesare  more 
abundant.    Cockchafers  thrive  best  in  the  lorn;-  open  stretches  of  grass  land, 
and  though   found   throughout  the 
plainS;  rarely  come  in  large  numbers. 
The  time  of  emergence  depends  upon 
climatic   conditions  and   is    usually 
regular.     A  species  that  emerges  at 
the  commencement  of  the  rains  does 
so  always,  whatever  the  date  of  the 
rains.     It  is  accordingly  possible  to 
expect    these     insects    at   regular 
seasons,  as  at  the  beginning    of  the 
rains,  and  to  take  measures  accord- 
ingly.    In    fruit    gardens,    certain 
plants   are  especially   attacked   and 
these  must  be  protected.     Only  ex- 
perience can  tell  which  plant  will  be 
attacked  in  any  locality  as  the  species 
have  differing  habits.     As  a  rule  it 
is  useless  to  spray  plants  with  lead 
arseniate,  as   the   beetles   feed   and 
poison  themselves  but  still  strip  the  plants.     Spraying  with  weak  contact 
poison  is  better  as  it  makes  the  plants  distasteful  but  the  effect  does  not 
last.     The  best  and  only  real  method  is  to  use  the  light  trap,  an  arrange- 
ment of  a  lantern,  two  reflectors  and  a  pan  of  jaggery  or  kerosene  and 
water.     Where  measures  are  required  on  a  larger  scale,  fires  are  useful. 

Fortunately  the  beetles  do 
not  fly  for  many  nightsand 
fires  are  not  required  for 
long ;  this  is  practically  the 
only  method  of  protecting 
crops. 

Cultivation  of  waste 
lands,  together  with  proper 
cultivation  of  arable  lahd^ 
are  radical  cures  for  such 
pests.  The  occurrence  of 
cocla^hafers    in    destructive 


Fig.  231. 

A  Cockchafer  Beetle. 

{Ilagnijied  four  times.) 


Fig.  232. 
A  Coc1cc7i,afer  Beetle.     {Magnified  four  times.) 


numbers  depends  largely  upon  the  extent  of  unculiivated  land  and  may 
be  looked  for  in  perhaps  every  other  season  in  places  Avhere  the  conditions 
for  increase  are  suitable.     Where  the  soil  is  ploughed  or  deeply  cultivated 


200 


BEETLE  PESTS. 


only  once  a  year  and  tliis  coincides  with  the  time  of  flight  of  the  beetles, 

the  larvae  and  pnpse  remain  undisturbed  in 
the  soil  for  the  whole  of  their  lives  and 
are  never  turned  out  fur  the  birds  to  eat. 

A  special  form  of  injury  to  the  crops 
occurs  when  the  ripening"  period  of  the 
millets  coincides  with  the  period  of  emer- 
gence of  cockchafers  ;  the  latter  then  feed 
upon  the  soft  grain,  settling  on  the  ears  of 
bajri  or  other  millets  at  night.  The 
attack  lasts  for  a  short  time  but  is  very 
serious,  the  actual  grain  being  destroyed 
in  a  wholesale  manner.  This  form  of 
injury  is  not  uncommon  in  the  plains. 
Very  little  can  be  done  to  check  such 
attacks  ;  fires  of  green  stuff  should  be  lit 
round  the  fields,  and  the  beetles  should  be 
disturbed  by  dragging"  a  rope  or  long  cloth 
brush  the  ears, 
the   beetles 


Fig.  233. 
Bed  Pumpkin  Beetle.    {Magnified.) 

through    the    field    so    as    to 

The  essential  thing  is  to  disturb 

as   they    will    not   live  long  and,  if  they  are 

prevented  from  feeding  for  a  few  nights,  the 

grain  will  be  secure. 

Another  special  form  of  injury  to  flower- 
ing plants  in  the  hills  is  caused  by  very 
small  cockchafers,  which  emerge  from  the  soil 
in  vast  numbers  and  feed  on  white  flowers 
such  as  roses,  spirseas,  etc.  These  feed  by 
day  and  are  attracted  to  anything  white,  or 
light  coloured.  They  can  be  trapped  on  a 
white  sheet  or  by  hanging  up  a  white  cloth 
over  a  large  pan  of  kerosene  and  water  j  the 
beetles  that  collect  must  be  periodically  gathered 
or  shaken  into  the  pan. 


Fig.  234. 

Black  Pumpkin  Beetle. 

{Macjnijied.) 


Leaf-eating  Beetles. 

A  large  class  of  Coleoptera  feed  upon  the  leaves  of  plants  in  a  n^anner 
similar  to  caterpillars.  These  beetles  eat  the  tissues  of  leaves,  either 
making  holes  in  them  or  completely  stripping  the  plants.  The  greater 
number  feed  upon  wild  plants,  specially  in  the  hills.  A  few  have  become 
pests  in  the  plains  and  are  abundant  in  the  crops. 


LEAP-EATING  BEETLES. 


201 


The  life  histories  of  these  insects  arc  for  the  most  part  unknown 
The  beetles  alone  do  harm  to  plants, 
and  it  is  not  yet  known  where  they  lay 
egg-s  or  where  the  larvjB  feed.  The  llicc 
Ilispa  is  an  exception,  its  life  history 
being-  degcribed  separately  (pay-e  114-). 
There  are  a  few  well  marked  and  fairly 
common  species  which  may  be  recognized 
by  almost  any  one  from  the  figures 
given  here,  and  there  are  a  number 
of  others  which  are  likely  to  be  found 
more  rarely  in  particular  localities.  The 
Ked  Pumpkin  Beetle^  is  an  orange  red 
beetle,  not  more  than  one  quarter  of 
an  inch  in  length,  which  is  found  com- 
monly attacking  melons,  gourds,  cucum- 
bers, and  other  cuciTrbitaceous  plants. 
It  is  not  limited  to  these  plants,  but  is 
a  common  pest  in  gardens  and  in  small 
patches  of  irrigated  lands.     The  ordinary  field  crops  are  rarely  attacked 


Fig.  235. 
The  Bice  Leptispa.     {Magnified.) 


Fig.  236. 
A  Tortoise  Beetle ;  erjf/s  {lower  left  figure)  ;  larva  {middle  row)  ;  pupa  {upper  right  and 

middle)  and  heefle. 

'  11.  Aulacophora fooeicollis.     Kust.     (Chrysomelida).) 


202 


feEETLE  PESTS. 


Witli  it  is  a  very  similar  beetle  ^  differing  only  in  having'  tlie  wing 
covers  black  instead  of  orange. 

A  smaller  blue  beetle  ^  (fig.  235); 
very  flat,  with  parallel  sides  and  no 
spines,  is  found  on  the  rice  with  the 
Rice  Hispa,  and  is  also  found  upon 
sugarcane.  The  life  history  is  not 
known,  but  is  probably  similar  to 
that  of  the  Rice  Hispa,  to  which  it 
is  closely  related.  Sweet  potatoes 
are  infested  by  a  small  golden 
tortoise  beetle  (fig.  236),  whose  flat 
green  grubs  feed  on  the  leaf  and 
cany  their  excrement  over  their  backs 
on  a  special  moveable  process.  The 
whole  life  history  is  passed  on  this 
plant  as  on  other  Convolvulacea,  but 
the  insects  are  rarely  abundant  and 
do  no  harm.  The  White  Weevil  is  a 
small  beetle  3  with  the  head  pro- 
duced in  front  into  a  short  beak 
(fig.  237)  ;  it  feeds  upon  cotton  leaves 


Fig.  237. 

T7/e  White  Weevil.     {Magnified  and 

natural  size.) 


Fig.  238. 
Green  Weevil.     (Magnified.) 


principally  and  is  commonly  found  upon  the 
plant.  If  the  plant  is  shaken  the  weevils 
fall  to  the  ground  and  lie  motionless,  sham- 
ming death.  If  it  were  a  pest,  this  habit 
coidd  be  made  use  of  to  destroy  the  beetle, 
but  no  case  is  yet  on  record  of  this  insect 
being  sufficiently  abundant  to  cause  harm. 

A  similar  but  larger  beetle  *  is  common 
on  indigo  ;  it  has  a  glistening  green  appear- 
ance, is  larger  than  the  White  Weevil 
and  is  sometimes  found  with  it  on  cotton 
(fig.  238).  A  few  other  weevils  have 
been  recorded  as  feeding  upon  different 
plants;  such  weevils  are  common  among 
wild  x*l''^'^ts,  and  are  rarely  found  upon 
cultivated  plants.     The   simplest  treatment 


'  125.  Aulacojthora  excattatn.     Baly.     (Chrysomelidffi.) 
'^  124.   J.epiispa  fygmaa.     Raly.     (ClirvsomcHdBC.) 
'      fi.  Mylloverus  maciilosii.t.     des  B.     (Curculiouidae<) 
*  1^8.  Astycus  lateralis.     Fabr.     (Curculionida;-) 


FLEA   BEETLES. 


20.3 


IS  to  shake  them  off  into  an  open  inverted  umbrella  or  a  kerosene  tin ; 
where  they  persistently  attack  valuable  plants  in  gardens,  a  dose  of  lead 
arseniatc  sprayed  upon  the  plants  is  sufficient  to  kill  them.  The  ordinary 
simple  butterfly  net  is  a  handy  weapon  against  all  such  beetles ;  it  is 
described  in  the  appendix  and  a  few  boys  with  nets  can  work  havoc  among 
beetles  on  garden  plants. 


Flea  Beetles. 

Fleas  are  those  small  active  insects  Avhich  infest  human  beings  and 
domestic  animals,  and  are  characterised  by 
great  leaping  powers. 

Flea  beetles  have  similar  leaping  powers, 
are  nearly  as  small  but  live  on  the  leaves  of 
plants.  They  are  very  small  insects,  usually 
less  than  one-eighth  of  an  inch  long  with 
the  shining  appearance  of  the  usual  beetle 
and  coloured  steel-blue  or  brown.  They 
bite  small  holes  in  the  leaves  they  infest, 
giving  a  very  characteristic  spotted  effect 
which  is  quite  clearly  recognisable.  The 
spotted  leaves  betray  them,  and  a  plant 
with  such  leaves  is  almost  sure  to  be  in- 
fested even  if  the  beetles  cannot  at  first 
sight  be  seen.  These  active  beetles  are 
difficult  to  catch. 

The  life  history  of  no  flea  beetle  has  been  worked  out  in  India.  In 
general  their  larviB  are  leaf-miners  tunneling  in  the  tissue  of  the  leaf 
between  the  upper  and  lower  epidermis.  The  larva  thus  lives  inside  the 
plant,  the  imago  outside.  Others  are  miners  in  the  stem  or  some  other 
portion  of  the  plants.  These  mines  are  seen  as  lines  or  blotches  on  the 
leaf,  but  as  they  are  produced  by  many  other  insects  beside  flea  beetle 
larvae,  care  must  be  taken  in  rearing  them. 

Few  species  are  destructive  in  India  and  little  is  known  about 
them.  They  are  found  as  occasional  pests,  but  not  doing  injury  to 
important  crops.  One  species  attacks  wheat  and  is  common  on  irrigated 
wheat  plots  in  experiment  farms.  Another  attacks  mustard  crops  but  is 
not  really  injurious.  San  hemp  is  eaten  by  a  brown  and  black  species 
which  appears  in  abundance  in  the  rains.  Brinjal  is  liable  to  attack,  as 
also  are  indigo,  vegetable  crops,  etc.  Rice  in  Burma  is  attacked  l)y 
another  species  (fig.  239),  and  there  are  doubtless  many  yet  to  be  found. 


Fig,  239. 
mce  Flea  Beetle.    {3Iagnijied.) 
On  the  right  the  hind  leg  to  /thoio 
the  immense  thigh  that  cha- 
racterises these  beetles. 


204 


BEETLE    PESTS: 


In  g-eneral  tlie  presence  of  these  insects  may  be  disregarded  unless 
they  come  in  extraordinary  numbers  or  are  infesting-  small  plots  of  valu- 
able experimental  crops.  No  treatment  will  affect  the  larvae  if  they  are 
in  the  plants.  Spraying  with  lead  arseniate  poisons  the  beetles ;  Bor- 
deaux mixture  is  a  specific  for  these  beetles  when  properly  prepared 
and  sprayed  on  the  plants.  The  bag  is  a  useful  mechanical  method  on 
wheat  or  rice  and  its  effect  is  enhanced  by  oiling  the  inside  of  the  bag 
with  kerosene  or  heavy  oil. 


Fig.  240. 

JEpilachna  Beetle, 

On  the  right  the  antenna,  on 

the  left  the  leg. 


Gpilachna  Beetles. 

On   brinjal   {Holanum    vielongena),    turia    {Luffa   acutangula),    dudhi 

{Lagenaria  vulgaris)  and  other  cucitrbitaceous 

plants,   and  on  many  wild  plants,  one  finds 

small  round  beetles  shaped  like  a  half  pea,  of 

a  dull  red  colour  with  black  spots.    They  feed 

upon  the  leaves,  taking  a  series  of  bites  off  the 

epidermis  and  producing  a  very  characteristic 

stippled  appearance  :  with  them  are  often  their 

larvse,  small  oval  grubs,  yellow  and  very  spiny. 

These  beetles  belong  to  the  true  lady-bird 

beetles  which  normally  eat  plant-lice,  mealy 

bugs  and  scale  insects ;  the  epilachnas  alone 

are  herbivorovis  both  as  larva  and  imago. 

The  life  history  is  similar  to  that  of  the  rest  of  the  family ;  the  eggs 

are  cigar-shaped,  yellow,  laid  in  clusters,  each  egg  on  end  side  by  side. 

Mr.  Haymann  found  that  one  beetle  laid  280  eggs. 

The  eggs  hatch  in  about  five  days,  the  young  feeding  at  once  upon  the 
epidermis  of  the  leaf.  "When  full  grown  the  larvae  are  one-quarter  of  an 
inch  long,  flattened  and  oval  covered  with  short  spines.  They  cling*  tightly 
to  the  leaf  and  move  slowly.  They  live  from  three  to  four  weeks,  and 
pupate  on  the  leaf,  the  pupa  being  attached  by  the  tail.  The  larval  skin 
is  not  completely  thrown  off  ;  after  four  to  six  days  the  imago  emerges. 

These  insects  are  most  abundant  from  July  to  November,  there 
being  several  broods  during  that  time.  The  beetles  live  throug'h  the 
cold  weather  and  emerge  about  March,  when  they  often  couple  and  lay 
eggs  if  a  food-plant  is  available.  ^ 

As  in  all  beetles  of  this  family,  they  can  live  for  long  periods  iintil 
fresh  food  is  available.  They  arc  injurious  simply  by  destroying  the 
leaves,  and  under  favoiirable  circumstances  become  abundant.  Garden 
crops  arc  injured,  field  crops  jn-actically  never.     In  gardens  the  simplest 


BLISTER    BEETLES. 


205 


way  is  to  destroy  the  beetles  by  hand-picking',  an  easy  matter  when  they 
are  few.  The  dang-er  is  that  useful  lady-bird  beetles  may  be  collected  by 
mistake,  but  if  tlic  yellow  spiny  g-mbs  are  found,  as  well  as  the  l)eetles,  it 
is  fairly  safe  to  destroy  them.  To  any  ouv,  who  lias  seen  both  kinds  of 
beetles,  there  is  no  difficulty  in  discriminating"  the  epihichnas.  In  serious 
cases,  a  spray  of  lead  arseniate  is  a  radical  (;ure  and  this  will  destroy  only 
the  epilachnas,  the  beneficial  beetles  not  eating-  the  poisoned  leaves. 


Fig.  241. 
Orange  Banded  Blister  Beetle 


Blister  Beetles. 

The  beetles  fig-ured  here  are  probably  familiar  to  every  one  who 
observes  insect  life  in  the  plains ;  they  represent 
the  most  common  species  of  this  group  in  India. 
Blister  beetles  are  characterised  by  having*  a 
somewhat  soft  integ-ument,  a  distinct  neck 
between  head  and  thorax,  and  elytra  which  do 
not  fit  tig'htly  to  the  side  of  the  abdomen  but 
look  as  if  they  belonged  to  some  other  insect. 
On  handling"  them,  an  acrid  yellow  liquid 
exudes  from  the  joints  of  the  legs.  They  are 
moderately  large  insects  with  good  powers  of  flight  and  may  be  found  by 
day  in  flowers  or  on  the  ground.  These  insects  appear  in  August, 
September  and  October  and  feed  upon  the  flowers  of  plants ;  exceptionally 
they  feed  upon  the  leaves  of  plants,  one  species  emerging  in  the  lower 
hills  in  vast  numbers  in  May  and  eating  certain  weeds.  Three  species 
are  prominent  in  the  plains,  recognisable  by  their  colouring*.  The  Banded 
Blister  Beetle  '  is  black  with  variable  bands 
of  orange  across  the  elytra ;  the  size  and 
colouring  are  very  variable,  orange  or  black 
predominating.  This  species  is  common 
throughout  the  plains  and  fields  from  August 
to  November  or  later.  It  appears  in  large 
flights,  settling  in  gardens  and  destroying 
the  flowers  of  pumpkins,  cucumbers,!melons, 
hibiscus,  cotton  and  other  large-flowered 
plants.  It  is  slow  in  flight  and  easily  cap- 
tured by  hand  or  with  a  small  net.  The 
Green  Blister  Beetle  ^  is  a  smaller  slender  insect,  the  elytra  a  vivid  green, 
the  neck  reddish.     It  is  associated  with  the  Brown   Bhster  Beetle,^  a 

^  50.  Mylahris  pustidata,  Fabr.  (CantharicliB.) 
^  40.  Cantharis  tenuicollis.  Pall.  (Cantharidpe.) 
'  39.  Cantharis  roiixi.     Cast,"  (Cautharidse.) 


Fig.  242. 
Orange  Banded  Blister  Beetle. 


206 


BEETLE    PESTS. 


Fig.  243. 

The  Green  Blister  Beetle. 

(Sliffktl^  magnified.) 


beetle  similar  in  shape  but  of  a  dull  brown  colour.     These  two  damag-e  a 
variety  of  crops,  including-  sorghum,  rice,  kutki  {Pauicum  miiiare),  bajra 

{Fennixi'tiiin  ti/phoidenm),  etc.,  by  dcstro^ang 
Ihe  flowers;  largo  numbers  emerge  as  these 
creeps  flower  and  settle  on  the  head,  biting  the 
anthers  and  stigmas  so  that  seed  is  not 
formed. 

This  results  in  a  large  or  total  loss  of 
grain.  The  attack  is  very  sudden,  and 
requires  to  be  checked  at  once.  The  insects 
feed  principally  in  the  morning,  hiding  in  the 
earth  or  on  the  plants  during*  the  hot  part  of 
the  day ;  they  remain  only  a  few  days  and 
again  disappear.  This  form  of  damage  is  by 
far  the  most  important  caused  by  these  beetles 
and  is  observed  or  reported  yearly  in  some  dis- 
tricts of  India. 

No  other  species  are  known  to  be  destruc- 
tive in  India  althougli  others  will  probably  be 
found  to  be  so.  Several  blue  species  are  common  in  the  plains  but  perhaps 
appear  at  a  time  wlien  no  crops  are  in  flower. 

The  life  history  of  these  beetles  is  unknown,  but  there  is  scanty 
evidence  that  it  will  prove  to  be  similar  to  that  of  European  and  Ameri- 
can species.  The  eg-gs  of  two  Indian  species  are  laid  in  large  masses 
on  the  soil  and  active  grubs  hatch  which  run  about  the  surface.  The 
life  histories  of  those  worked  out  elsewhere  are  of  extreme  interest, 
being  passed  in  the  nests  of  bees  or  wasps,  or  in  the  egg  masses  of  locusts. 
The  active  larva  that  hatches  from  the  egg  attaches  itself  to  a  bee 
and  is  carried  to  its  nest,  or  seeks  out  the  egg  mass  of  a  locust.  In  all 
cases  known  the  larval  life  is  a  semi-parasitic 
one,  and  there  is  a  curious  metamorphosis  in 
the  larval  life,  the  larva  assuming  two  or  more 
distinct  forms  at  successive  periods. 

Blister  beetles  are  useful  in  medicine,  the 
oil  of  certain  species  having  the  power  of  blis- 
tering the  human  skin.  The  extract  of  the 
dried  beetle  is  used  for  this  purpose.  In  India 
these  beetles  are  used  in  a  somewhat  similar  manner.  In  Baluchistan, 
for  instance,  the  "  Gojak ''  beetle  ^  is  soaked  in  milk  and  the  fluid  poured 
on  the  bald  spots  to  cure  mange  (R.  Hughes-Buller).  When  the  beetles 
'  Closely  allied  to  Mylalris  piistidaia. 


Fio.  244. 
Brown  Blister  -Beetle. 


PALM    nEETLES. 


207 


Tm.  215. 
Brown  Blister  Beetle. 


attack  crops,  vigorous  measures  must  be  taken  at  once  to  drive  tliem  out. 
Hand-collecting-  is  laborious ;  active  boys  with  hand- 
nets  will  catch  far  more,  and  a  simple  hand-net  of 
bamboos  and  musliu  is  easy  to  make  (figs.  C  and  D, 
])ao-e  289). 

Fires  covered  with  green  materials  are  useful 
if  the  smoke  hangs  in  the  crops  and  the  air  is  still. 
In  the  case  of  low  crops  such  as  rice,  the  useful 
bag  can  be  run  through  quickly,  and  where  they 
are  taller,  a  rope  or  a  strip  of  cloth  can  be  fitted  to 
two  bamboos  and  ]>ulled  over  the  ears;  vigorous 
measures  to  worry  the  insects  in  the  morning'  are 
all  that  is  required  and  in  a  few  days  the  seed  is  set 
and  the  beetles  disappear.  In  gardens,  the  banded  beetle  destroys 
flowers ;  there  is  no  remedy  available  but  to  collect  them  by  hand  or  with 
the  net,  which  is  not  difficult  as  the  flights  of  beetles  soon  pass  away. 
Collected  beetles  are  easily  killed  in  hot  water  or  in  water  with  a  film  of 
kerosene  over  it. 

Palm  Beetles. 

Two  beetles,  of  distinct  habits  and  appearance,  attack  palms,  includino- 

the  toddy,  palmyra  and  cocoa- 
nut-palm.  Each  is  destructive 
in  a  distinct  manner  and  both 
are  found  widely  spread  over 
the  plains  of  India,  The  two 
cannot  be  confused  in  their 
appearance  or  their  work. 

The  Rhinoceros  Beetle^  is 
a  large  thick-set  black  beetle, 
somewhat  over  two  inches 
long  and  one  inch  broad  j  its 
appearance  is  best  realised  from 
the  figure. 

This  insect  flies  at  night, 
coming  into  houses  attracted 
by  lights.  It  feeds  upon  the 
soft  tissues  of  the  palms, 
attacking  the  unopened  leaf 
or    the    base   of  the    fruitino- 


Fig.  246. 
The  Rhinoceros  Beetle. 


^  X2Q.  Oi'i/cfes  rhinoceros,     L.     (ScarabfEidiB.) 


208 


BEETLE    PESTS. 


stem  and  eating-  its  way  into  the  soft  heart  of  the  plant.  In  so  doing 
it  injures  the  rolled  up  new  leaves,  which  show  signs  of  its  work  Avhen 
they  open,  and  Avounds  the  tree.  In  itself  it  does  little  harm  and  in 
Ceylon  is  kept  in  cheek  by  extraction  from  the  tree  with  a  stiff  Avire. 
Mr.  P.  B.  Haig  has  reported  that  in  Kanara  tliis  beetle  kills  the 
cocoanut-trees  occasionally  and  that  an  attacked  tree  yields  no  toddy. 

Its  life  history  is  known  to  the  toddy-tappers,  Avdio  find  its  grub  in 
dung  heaps  and  in  decaying  vegetable  matter.  The  grub  is  an  immense 
soft  Avhite  larva,  leg- 
less and  of  a  most 
striking  appearance ; 
it  is  quite  common 
in  dung  heaps  and 
decomposing  A^egeta- 
tion.      The  beetle 

really  does  injury  by 
attracting  the  more 
serious  enemy  to  the 
palm  tree,  the  Red 
Weevil.  This  insect 
comes  to  trees  wounded 
by  the  Rhinoceros 
Beetle  and  lays  eggs 
in  the  Avound.  For 
this  reason  it  is  de- 
sirable to  check  the 
beetle  by  the  de- 
struction of  its  young 
and  by  capturing  it 
on  the  attacked  trees. 

The  Red  WeeviP  is  a  more  slender  insect,  of  a  red-broAvn  colour, 
with  a  conspicuous  curved  snout,  about  one  and  a  half  inches  long.  Its 
life  history  is  as  follows.  The  weevil  lays  eggs  singly  in  the  tissues  of 
the  palm-tree  by  means  of  her  long  ovipositor  ;  these  eggs  are  deposited 
in  the  wounds  made  by  the  Rhinoceros  Beetle,  in  cuts  made  by  tapping, 
in  cracks  or  at  the  base  of  the  leaf  stalk ;  in  fact  Avherever  in  the  tree 
the  AA^eevil^s  ovipositor  reaches  the  tender  tissues,  she  lays  egg».  In 
Ceylon  it  is  said  that  the  eggs  are  laid  only  in  trees  that  have  reached 
the  fruiting  period,  but  this  is  not  yet  certain.  The  grubs  that  batch 
tunnel  in  the  soft  tissues,  feeding  on  them  and  gradually  working  down 

^  J41.    Rhynchophoriis  sif/naticoJIis.     Chevr.      (CurculionidiE.) 


Fig.  247. 
J?aIiH  Weevil.     Below,  Ihe  Cocoon. 


PA.LU   WEEVIL.  209 

into  tlie  stem ;  a  large  number  of  eggs  are  laid  in  each  plant  and  sooner 
or  later  the  plant  probably  dies.  The  grubs  when  full  fed  prepare  a 
coeoon  of  the  twisted  fibres  of  the  stem ;  how  the  grub  in  the  seclusion  of 
the  stem  is  able  to  prepare  this  cocoon  is  one  of  the  marvellous  things 
in  the  life  of  this  insect.  The  beetle  presently  emerges  from  this  cocoon 
and  comes  out  of  the  tree. 

The  life  history  in  this  case  probably  occupies  one  year  Init  has  not 
been  ascertained  in  India.  The  insect  is  destructive  to  cocoanut  palm 
in  Ceylon  and  the  Straits  Settlements ;  another  species  is  injurious  to 
palms  in  Honduras  and  the  West  Indies  in  the  same  way.  A  great 
deal  has  been  written  about  these  insects  in  these  countries,  where  they 
are  far  more  important  than  in  India.  In  Ceylon  legislation  is  proposed 
against  them,  the  law  compelling  every  owner  of  trees  to  take  certain 
measures  against  the  weevils. 

All  remedies  are  directed  to  two  ends,  to  prevent  egg-laying  in  the 
palm-trees,  to  destroy  all  weevils  that  breed.  For  the  first,  the  Rhinoceros 
Beetle  must  also  be  destroyed,  and  in  Ceylon  this  is  done.  Secondly,  the 
cuts  made  by  tappers  must  be  so  treated  that  the  weevils  cannot  lay 
their  eggs  there ;  this  is  effected  in  Gujarat  by  smearing  the  cut  with 
the  juice  of  Euj)horhia  neriifolia.  Blandford  suggested  a  mixture  of  tar 
and  sand  for  the  Honduras  weevil,  and  it  is  likely  that,  if  available,  tar 
^^■ould  do  equally  well  in  India.  As  it  is,  clay  must  be  used  or  any  other 
substance  which  the  tapper  can  obtain  and  which  will  keep  the  weevil 
from  the  cut.  This  treatment  must  include  other  cuts  and  wounds,  in 
fact  all  openings  at  which  the  weevil  could  lay  eggs. 

To  destroy  the  weevils  it  is  necessary  to  burn  badly  attacked  trees, 
and  the  legislation  in  Ceylon  is  designed  to  make  this  compulsory.  A 
tree  that  is  infested  and  dies  is  a  source  of  danger  to  all,  since  the  weevils 
that  are  in  it  come  out  and  infest  other  trees.  "Where  trees  are  only 
lightly  attacked  and  the  attack  is  seen  in  time,  the  grubs  are  cut  out 
and  the  wound  treated  with  tar  and  mud.  Mr.  Green  in  Ceylon  has 
got  better  results  by  treating  attacked  trees  with  carbon  bisulphide,  and 
this  is  deserving-  of  trial  in  India. 


CHAPTER  XVlI. 

LOCUSTS,  GRASSHOPPERS,  SURFACE  BEETLES,  AND 
BURROWING  INSECTS. 

LOCUSTS  are  probably  the  most  familiar  pests  discussed  in  this 
volume,  and  are  here  treated  with  the  grasshoppers  and  other  orthop- 
terous  insects  to  which  they  are  allied.  Locusts  do  no  great  aggregate  harm 
compared  with  the  attention  they  attract,  though  the  sight  of  fields 
stripped  by  a  locust  swarm  is  very  impressive.  If  money  values  could 
be  ascertained,  any  one  of  the  major  pests  probably  does  more  aggregate 
damage,  working  constantly,  scattered  over  all  India,  but  not  laying 
waste  a  tract  in  the  thorough  manner  of  the  locust. 


Fig.  248. 
A  Common  Grasshoirper. 


GKAssuorrKus.  211 

Surface  <>rasslio])porf!:,  \vlueJi  do  a  ifToat  aniouiil  ol  liann  in  India, 
arc  here  separated  from  the  ordinary  grasshoppers  and  discussed  as  a 
distinct  class  of  pest  (page  220). 

Grasshoppers. 

Among-  the  most  common  insects  are  the  grasslioppers^  active  insects 
which  live  in  fields  and  jungles,  leaping  and  Hying  readily  when  disturbed. 
They  are  recognisable  most  easily  by  the  very  large  hind  legs,  with  which 
they  leap.  The  body  is  hard,  not  hairy  or  covered  with  scales ;  the  wings 
project  beyond  the  end  of  the  abdomen  and  are  often  coloured,  the  antenna) 
are  quite  short. 

Grasshoppers  and  locusts  together  make  up  one  family  of  insects. 
It  is  generally  supposed  that  any  large  grasshopper  is  a  locust  and  this 
word  is  commonly  used  without  a  clear  idea  of  its  true  meaning.  When 
an  insect  belonging  to  the  family  called  grasshoppers  becomes  exceedingly 
numerous  and  forms  large  swarms,  which  migrate  from  place  to  place,  it 
is  called  a  locust. 

There  is  no  difference  in  structure  between  locusts  and  grasshoppers  ; 
the  distinguishing  feature  of  the  locust  being  that,  when  very  abundant, 
all  collect  together  into  swarms  and  move  from  place  to  place. 
'  There  are  many  large  grasshoppers  in  India  which  never  form  into 
swarms  and  migrate ;  only  two  true  locusts  are  known  in  India,  and  these 
are  almost  identical  with  the  large  grasshoppers  (pages  212-14). 

Grasshoppers  occur  throughout  India  in  the  plains,  and  in  the  hills 
up  to  the  snows.  Many  si)ecies  live  in  the  forests,  others  in  grass  lands, 
a  few  in  the  crops  and  cultivated  land.  The  life  history  of  all  is  not 
known  in  detail,  but  all  have  similar  habits.  The  female  lays  eggs  in  the 
ground,  depositing  them  in  a  compact  cluster.  The  young  that  hatch  are 
very  small,  active  insects  which  resemble  the  full  grown  insects  in  general 
appearance.  They  have  no  wings  when  first  hatched,  which  appear  only 
after  there  have  been  several  moults  and  the  insect  is  half  grown.  As  in 
all  insects  the  wings  are  fully  developed  with  the  last  moult.  It  must 
be  remembered  that  any  grasshopper,  however  small,  that  has  fully 
developed  wings  and  can  fly,  is  full  grown  and  can  grow  no  further. 
The  number  of  moults  varies  with  different  species,  from  five  to  seven  or, 
exceptionally,  eight. 

The  wings  appear  after  the  third  moult  as  very  small  lobes  on  the 
second  and  third  thoracic  segments,  growing  larger  at  each  moult.  The 
colouring  of  the  young  grasshopper  is  commonly  distinct  from  that  of 
the  full  grown  insect  and  may  change  at  least  twice  during  nymphal 
life*     This  is  due  to  the  changed  eiivironmeiit  of  the  insects  at  different 

p  % 


2l2  LOCUSTS,    HOPPEllS,    SURFACE    BEETLES,    ETC. 

periods  or  even  to  the  changing  colour  of  the  vegetation  as  the  season 
advances. 

In  general  the  young  are  coloured  green  to  accord  with  the  green 
vegetation  in  which  they  live,  and  the  adults  in  greys,  browns,  and  neutral 
tints  which  blend  with  the  light  and  shade  o£  the  drier  grass  or  vegetation 
in  which  they  live.  In  no  group  of  insects  is  this  form  of  protective 
colouring  so  universal  or  so  beautifully  shown.  Rarely  they  are  strikingly 
coloured  and  exhibit  ^'warning  colouration"  in  conjunction  with  unpleas- 
ant taste.  So  far  as  is  known  grasshoppers  are  exclusively  herbivorous. 
The  period  of  the  life  history  varies  greatly  and  only  a  few  species  have 
been  worked  out.  Some  hibernate  as  eggs,  others  as  perfect  insects,  and 
there  may  be  one,  two  or  several  broods  in  the  year. 

The  two  locusts  and  the  Rice  Grasshopper  are  dealt  with  separately 
(pages  214  and  119) ;  a  separate  section  is  also  devoted  to  the  ground 
grasshoppers  which  injure  crops  in  a  special  manner.  Few  other  grass- 
hoppers are  known  to  be  destructive,  though  a  number  of  species  have 
been  sent  in  as  pests  or  as  locusts. 

The   Painted   Grasshoj)per^  is   a  large   species  coloured  in  blue  and 


Fig.  249. 
The  Fainted  Grasshopper. 

yellow  when  full  grown,  found  abundantly  on  the  akh  plant  {Calotroins 
spjj.).  Its  young  are  coloured  yellow  with  black  stipples  and  red  spots, 
exhibiting  warning  colouration  as  do  the  parents.  The  Black-spotted 
Grasshopper^  is  a  large  species  coloured  in  black,  brown  and  white,  which 
lives  in  the  crops  and  feeds  specially  upon  cotton.  The  young  (fig.  251) 
are  green  with  a  pink  strij)e  at  the  posterior  edge  of  the  thorax  ;  this 
species  is  found  at  aU  seasons  of  the  year,  having  no  regular  broods. 

^Poecilocera  picia.     F.  (Acridiidse.)    |    ^49.  AcricUum  aeruginosum.     Burm.  (Acridiidse.) 


GRASSHOPPERS. 


213 


It  is   constantly   confused   witli   the   Bombay  Locust   which   it   closely 
resembles. 


Fio.  250. 
The\BlacTc-spotted  Qrasshopper. 


Another    large   species   very   common  in  the   plains  is   the  Snouted 
Grasshopper;^  a  long  slender  grasshopper   characterised  by    the   sharp 


%^ 


Fig.  251. 
Tonny  oj  BlacTc- spoiled  Grasshopper.    Colour  green.    Firtt,  second  and  penultimate 

stages  shown. 

*  Tryxalis  turrita  and  other  species. 


214 


LOCUSTS,    HOPPEitS,    SURFACE    BEETLES,    ETC. 


head  and  flat  antennae.     It  is  green  or  coloured  in  a  beautiful  combina- 
tion of  browns  which  make  up  a  general  '  dry  grass  colour/     There  are 


<n^' 


Fid.  252. 

The  Snouted  Grasshopper. 

a  large  number  of  smaller  forms  common  in  the  plains  and  still  more  in 
the  hills.     None  can  be  reckoned  to  be  specific  pests  of  special  crops. 

The  principal  safeguard  against  grasshoppers  is  clean  ciiltivation  j 
fallow  lands  should  not  bear  a  crop  of  weeds  and  waste  lands  should 
o-row  good  grass.  Waste  strips  between  fields  are  a  constant  danger 
unless  fed  down  or  planted  with  one  variety  of  grass.  When  grass- 
hoppers appear  in  numbers  in  crops,  an  attempt  should  be  made  to  trace 
them  to  their  breeding  place,  which  is  probably  waste  land  near  by. 


Locusts. 


Two   species    of      '  grasshopper'    come     within    our    definition    of 
locusts,  that  is,  grasshoppers   that   form   swarms   and    migrate.     These 


Fig.  253. 
The  Migratory  Locust. 


are  the  Migratory  or  North- West  Locust  1   and  the  Bombay  Locust.^ 

>  66.  Acridium  peregrhmm.  Oliv.   (Acridudffi.)  |  '46.  Acridium  succinctum.  L.  (Acridlidse.) 


LOCUSTS,  215 

other  species  may  prove  to  be  locusts  but  have  not  migrated  in  swarms 
in  recent  years. 

These  two  species  are  constantly  confused,  not  only  with  each 
other,  but  with  such  insects  as  the  Black-spotted  Grasshopper  and  other 
large  grasshoppers.  Both  are  over  two  inches  in  length  and  half  an 
inch  across  the  thorax  ;  this  eliminates  all  but  a  few  insects  in  India. 
Green  does  not  enter  into  the  colour  scheme  of  either.  The  North- 
West  Locust  is  a  uniform  purple  red  or  yellow  with  no  stripes,  with 
wings  uniformly  spotted  from  base  to  apex  and  with  indented  lines 
round  the  prothorax.  The  Bombay  Locust  has  streaks  of  colour  on  the 
prothorax  and  wings,  very  faint  indented  lines  and  is  very  variable 
in  colour.     It  can  be  at  once  distinguished  from  the  North- West  Locust 


'<^ 


Fig.  254. 
The  Bombay  Locust. 

by  its  stripes  and  by  the  absence  of  indented  lines.  It  will,  however,  be 
confused  with  the  Black-spotted  Grasshopper  -which  is  of  robuster  build, 
conspicuously  blotched  in  black  and  white,  with  a  large  white  blotch  on 
the  side  of  the  prothorax ;  the  latter  never  varies  in  colour. 

The  figures  above-  help  in  distinguishing  the  species,  but  owing  to 
the  colour  variation  of  the  Bombay  Locust  it  will  always  be  confused 
with  the  other  species  unless  actual  specimens  are  examined. 

The  North-West  Locust  extends  over  Baluchistan,  North- West 
India,  South  Afghanistan,  Persia,  Arabia,  Cyprus,  and  Northern  Africa, 
with  permanent  breeding  grounds  in  widely  separated  localities  in  this 
vast  area. 

From  North- West  India  it  extends  in  a  general  easterly  and  south- 
easterly direction  over  the  Punjab,  Central  India,  the  northern  division 
of  the  Bombay  Presidency  into  the  United  Provinces^  Bengal,  Assam, 
?ind  as  far  south  as  Madras. 


216 


LOCUSTS,   HOPPEES,    SURFACE   BEETLES,   ETC. 


Tlie  permanent  breeding  gronnds  appear  to  be  in  the  sand  hills  of 
Western  Rajputana,  in  Baluchistan,  Southern  Afghanistan,  and  Persia ; 
from  these  places  swarms  fly  over  Rajputana  into  India.  This  locust 
lays  its  eggs  in  sandy  places,  depositing  a  single  mass  containing 
from  fifty  to  one  hundred  eggs.  These  hatch  in  about  three  weeks  and 
the  hoppers  are  at  first  green,  later  black.  They  are  said  to  moult  four 
times,  but  probably  do  so  more  often.  Maturity  is  said  to  be  attained  in 
from  one  to  two  months,  after  wliioh  they  form  into  swarms  and  fly. 
Within  another  two  to  four  months  they  couple  and  lay  eggs,  provided 
a  suitable  spot  is  found. 

The  whole  life  apparently  occupies  from  five  to  seven  months,  and 
there  are  in  India  two  broods  in  the  year.  There  is  apparently  no 
regularity  in  the  periods  of  egg-laying,  which  depend  upon  the  amount 
of  food  available  and  the  local  conditions.  An  insect  that  migrates  over 
vast  distances  will  probably  have    changed  habits  in  various  localities 


Fig.  255. 
Tiggs  and  Nymphs  of  the  Migratory  Locust. 

and  be  dependent  upon  climatic  conditions.  Wliilst  the  winged  insects 
have  the  usual  habit  of  flying  in  swarms,  the  young  form  swarms  which 
move  over  the  ground  and  devour  all  green  stuff  within  reach.     In  this 


MIGRATORY   LOCUST. 


217 


Fig.  256. 

Young  Bombay  Locust  after  third  moult. 
{Magnified  jive  times.) 


state  tho  destruction  is  enormous  since  the  insects  strip  whatever 
vegetation  they  encounter.  The  winged  insects  may  be  as  destructive, 
but  as  a  rule  their  ravages,  being  spread  over  longer  distances,  are  not  felt  so 
acutely. 

A  great  deal  has  been  written  about  the  North- West  Locust  and 
advantage  is  taken  of  its  peculiar  habits  to  destroy  it  wholesale.  The 
reader  should  consult  the  long  article  in  the  Journal  of  the  Bombay 
Natural  History  So- 
ciety for  1891  (page 
242). 

The  essential  fea- 
tures of  this  locvist 
are  that  it  has  per- 
manent breeding 
places  in  North- 
Western  India  from 
which  it  migrates ; 
that  it  apparently 
breeds  twice  a  year 
and  lays  its  eggs  in 
special  sandy  places,  and  that  the  young  form  swarms  which  hop  from 
place  to  place.  It  is  possible  to  destroy  the  eggs  in  the  permanent 
breeding  places  or  at  least  to  destroy  them  when  they  lay  eggs  in 
accessible  places  ;  it  is  also  possible  to  destroy  the  armies  of  hoppers  by 
simple  mechanical  methods  ;  these  two  measures  are  extensively  carried 
out  against  this  locust  in  Cyprus  and  Algiers  and  form  the  basis  of 
methods  of  checking  the  pest. 

The  Bombay  Locust  breeds  most  extensively  near  the  Western 
Ghats,  a  line  of  forest  hills  bordering  the  sea  from  the  Thana  District 
to  Coorg,  the  chief  breeding  ground  being  in  the  neighbourhood  of  Goa, 
not  in  the  forest  but  outside  in  the  open  grass  lands.  It  also  breeds 
all  over  the  plains  of  Southern  India  in  suitable  places,  and  is  found 
in  Assam,  Burma,  and  throughout  the  whole  of  Peninsular  India. 
Where  it  becomes  abundant,  it  assumes  the  characteristics  of  a  locust ; 
elsewhere  it  is  an  ordinary  grasshopper,  forming  part  of  the  regular 
plains'  fauna. 

From  the  Western  Ghats  it  spreads  in  swarms  over  Bombay, 
Mysore,  parts  of  Madras,  over  Hyderabad,  the  Central  Provinces  and 
parts  of  Central  India. 

This  is  exceptional  and  occurs  only  rarely.  This  locust  breeds  only 
in  damp  places,  laying  its  eggs  in  wet  soil;  it  lays  a  mass  containing 


218  LOClTSTSj    HOPPERS,    SURFACE    BEETLES,   ETC. 

abont  ono  hundred  eggs  (fig.  25),  which  hatch  in  about  six  weeks. 
The  young  are  green  and  complete  their  development  in  about  two 
months  (figs.  27,  28,  257,  258). 

Eggs  are  laid  with  the  first  heavy  rains  in  June  or  Jvdy,  and  the 
perfect  insect  emerges  in  October.  From  October  to  June  it  lives  as  a 
flying  insect ;  its  colour  is  at  first  brown  with  light  stripes,  forming'  the 
'  dry  grass  ■*  colour  which  is  protective  to  it  in  the  long  dry  grass  in  which 
it  lives.  It  then  forms  swarms  and  becomes  suffused  with  a  vivid  red, 
which  persists  during  about  four  months ;  throughout  this  time  it  lives  in 
immense  swarms  in  the  Ghat  forests  until  in  April  and  May  it  scatters. 
In  1904  these  swarms  spread  over  an  immense  area  and  in  May  broke 
up,  single  locusts  being  found  scattered  throughout  this  area.  This  is 
preliminary  to  coupling,  which  commences  with  the  rains  ;  the  locust  now 
assumes  a  darker  colouring,  the  red  giving  place  to  blacks  and  browns  ; 
this  colour  scheme  hides  the  insect  when  sitting  on  wet  grass-land  or 
soil  where  it  lays  its  eggs. 

The  life  cycle  occupies  one  year,  and  egg-laying  is  performed  at 
this  special  season.  The  young  are  found  scattered  through  the  long 
green   grass  during  the  rainy  months  and  do  not  form  swarms.     The 


Fia.  257. 
Young  Bomlay  Locust  after  third  moult.     {Magnified  five  times.) 

V 

earliest  swarms  are  found  in  October  when,  as  the  grass  ripens,  the  insects 
enter  the  crops,  feed  there  and  then  migrate  back  to  the  forests.  The 
forest  region  is,  therefore,  the  home  of  this  locust  which  migrates  only  to 
breed  or  when  extraordinarily  abundant. 


BOMBAY    LOCUST, 


219 


The  damage  is  caused  entirely  by  the  winged  locusts,  first  in  the 
ripening  khai^f  crops,  later  in  the  hilly  districts  during  the  winter 
months. 


Fig.  258. 
Bombay  Locust,  before  the  last  moult. 


{Magnified  tioice.) 


The  methods  in  use  against  the  North- West  Locust  are  here 
impossible  owing  to  the  different  habits.  The  eggs  are  rarely  found  in 
large  numbers  and  are  usually  scattered  over  a  large  area.  The  young 
are  not  found  in  swarms  but  scattered  in  grass-lands.  The  winged 
insects  fly  in  swarms  for  several  months  and  Uve  for  eight  months  in  all. 
The  measures  actually  adopted  against  this  locust  included  the  destruc- 
tion of  the  hoppers  by  means  of  bags  and  cloths,  the  destruction  of 
swarms  at  night  during  the  cold  weather,  the  destruction  of  coupKng 
locusts  by  hand  and  the  collection  of  eggs,  all  under  the  inducement  of 
rewards  paid  for  the  amount  collected.  The  Bombay  Locust  appears  to 
have  emerged  in  immense  swarms  in  1883-84.  and  in  1903-04.  A  full 
account  of  the  latter  outbreak  has  been  pubUshed  separately. 

Locusts  in  India,  as  elsewhere,  are  attacked  by  parasites  and 
enemies.  The  winged  individuals  are  infested  by  the  young  of  a  large 
red  mite^  and  are  parasitised  by  at  least  one  and  possibly  more  species 
of  parasitic  flies.''  The  eggs  are  parasitised  by  an  ichneumon  and  a 
fly,  are  eaten  by  grubs  and  are  infested  with  a  peculiar  worm.     Crows 

*  17.  Trombidimn  grandissimum. 

»  Miltogramma  duodecim  punctata.     Big.     (TacbiuidtE.) 


220 


LOCUSTS,    HOPPEKS,    RTIRPACE   BEETLES,   ETC. 


eat  locusts  and  destroy  their  eggs  and  the  '  rosy  pastor '  or  pcari  bird  is 

supposed  to  destroy  a  large  number  of  winged  locusts. 

It  is   probable  that  other   species   of   grasshoppers  will  be  found  to 

form  swarms  and  behave  as 
locusts  under  exceptional 
circumstances,  but  no 
species  are  known  to  do 
so  at  present  in  India, 
There  has  been  great 
confusion  on  this  point 
owing  to  the  difficulty 
of  identifying  insects 
believed  to  be  locusts.  It 
is  probably  correct  to  say 
Fig.  259.  that,  except  in  the  case  of 

Fhj  parasitic  upon  Locusts.  ^^^^i     Iqq^\      SWarms,      no 

insect  except  the  two  discussed  above  can  be  regarded  as  a  true  locust  in 
India, 


Surface  Beetles  and  Grasshoppers. 

A  number  of  insects  confine  their  attacks  to  young  plants  just  out  of 
the  soil,  destroying  the  germinating  plants  as  they  push  above  the 
surface   and   preventing   the   crops  from  becoming   established.     These 


Fig.  260. 
Fly  parasitic  on  the  Ff/t/s  of  the  North-West  Locust,     (Magnified) 


Surface  BEETLESi 


22l 


Fig.  261. 

Surface  Weevil.     (Maffnified.) 


pests  are  of  very  general  occurrence  throughout  India  both  in  field  and 
garden  crops.     They  form  a  clearly  defined  group   of  pests,   including 

insects  of  widely  separ- 
ated affinities,  but 
united  by  their  peculiar 
habits  and  methods  of 
feeding. 

All  are  adapted  to 
living  on  the  surface 
of  the  soil;  most  are  of 
the  dull  brown  colour  of 
the  freshly  ploughed 
earth  and  are  difficult 
to  find  when  at  rest  on 
the  surface  :  they  in- 
clude the  surface  beetles,  small  earth-coloured  weevils,  not  exceeding  one 
quarter  of  an  inch  in  length,  similar  to  the  species  figured  here  :  also  the 
surface  grasshoppers,  which  are  either  flattened,  with  a  rough  upper 
surface  and  exactly  earth-coloured,  or  they  are  similar  to  the  common 
grasshoppers  but  coloured  in  brown  so  as  to  escape  notice  on  the  soil. 

The  beetles  live  on  the  soil,  hiding  in  cracks,  under  stones  and  in 
burrows;  they  emerge  daily  and  feed 
on  the  young  plants,  being  very  abund- 
ant at  the  time  when  the  kharif  or 
rabi  crops  are  sown.  Their  life  histories 
are  unknown,  the  grubs  being  probably 
borers  in  wild  plants.  The  grasshop- 
pers are  similar  in  their  life  histories  to 
others  of  this  group;  they  lay  eggs  in 
the  soil,  from  which  the  little  hoppers 
hatch;  the  whole  life  is  passed  in  the 
fields  and  under  favourable  circum- 
stances they  become  very  abundant. 
Most  breed  rapidly  and  regularly,  with 
several  broods,  but  some  appear  only 
at  regular  intervals  such  as  once  or 
twice  in  the  year.  All  are  herbivorous, 
and  their  ravages  in  the  estabUshed 
crops    are    not    observed    as   they    are  ii'io-.  262. 

not    sufficiently     numerous    to   do     harm.        A  common  Ground  Beetle  that  feeds 
_^  ...  .        .  OH  decay tnj  leaves  ana  IS  imsta/cen 

They    are     injurious      to     germinating  for  a  pest.  (Magnified.) 


00  0. 


LOCUSTS,    HOPPERS,    SUEPACE  ^EETLES,   ETC. 


Fig,  263. 

A  common  Surface  Grasshopper. 

{SlifjMli)  magmjied.) 


crops  owing-  to  tlic  peculiar  conditions ;  large  areas  of  land  are  cleaned, 
weeded  and  sown  ;  there  is  no  food   in  the  fields  but  the  g-erminating 

seeds,  which  offer  a  peculiarly 
tempting  diet  to  these  insects ; 
a  few  insects  can  destroy  a 
very  large  number  of  these 
tender  shoots  and  the  destruc- 
tion becomes  very  serious ; 
the  crop  is  resown  and  again 
eaten.  The  destruction  of 
successive  sowings  and  the 
delay  in  establishing  the 
crop  may  prove  very  serious, 
and  there  are  many  cases  where 
the  crops  cannot  be  established. 
The  attacks  are  more  general  in 
rabi  sowings  but  occiu-  in  kharif 
sowings  especially  when  heavy 
rain  has  not  checked  the  insects. 
Early  sowings  are  most  attacked 
under  some  conditions,  later  ones 
under  others,  which  is  a  matter  of  climate  and  rainfall. 

Wheat,  barley,  oats,  opium,  tobacco,  maize,  sorghum,  cane,  gram, 
cotton,  minor  millets  and  vegetable  crops  are  all  attacked,  and  these 
insects  have  been  observed  or  reported  from  widely  separated  districts  of 
India.  The  number  of  species  concerned  is  not  fully  ascertained  and  it 
is  unnecessary  to  distin- 
guish them. 

The  methods  of  treat- 
ment vai'y  according  to  the 
natui'e  of  the  ci'op  and  the 
insect*  One  general  pre- 
ventive is  available  in 
almost  all  cases,  which  is 
to  provide  the  insects  with 
alternative  food  so  that  tliey 
will  not  eat  the  seedlings. 
The  common  weeds  and  grass  in  the  held  will  provide  this  where  it  is 
possible  to  defer  weeding  until  the  seed  is  well  germinated  and  estab- 
lished. "Where  this  is  not  possible,  another  crop  can  be  sown  lightly  over 
the  field  so  as  to  germinate  earlier  and  provide  food.      The  cultivator 


Fig.  264, 

The  small  Ground  Grasshopper. 

[Magnijied  twice.) 


St/RtACE   BEETLES. 


223 


of  opium  in  some  parts  of  India  sows  mustard  with  liis  opium  to  protect 
the  latter,  weeding"  out  the  mustard  when  no  longer  recpiired.  Sowing 
maize  with  cotton,  or  sorg-hum  and  maize  with  cane  effects  the  same 
object.  The  practice  of  sowing*  mixed  seeds  in  irrigated  plots  serves  the 
same  purpose,  the  valuable  plants  being  protected  by  the  dense  growth 
which  is  removed  as  soon  as  the  plant  is  established. 

In  Gonda  (Oudh)  the  opium  cultivator  is  said  to  strew  chips  of 
pumpkin  through  his  field  to  attract  the  beetles  which  gather  there  and 
are  destroyed.  This  is  the  simplest  and  most  rational  method,  whenever 
it  is  possible.  In  the  case  of  grasshoppers  only,  the  ordinary  bag  and 
frame  can   be  run   over  the   fields  to   sweep  up   the  grasshoppers  when 

the    seed    is    sown.     This 

will  not  collect  the 
beetles  which  do  not 
jump  in  the  air  when 
the  bag  approaches  and 
can  be  used  only  against 
grasshoppers.  The  neces- 
sary expenditure  of  a  few 
rupees  for  bags  and  an  anna 
or  so  an  acre  for  labour  is 
well  worth  incurring  where 
grasshoppers  are  abundant. 

Flooding  is  useful  where  it  can  be  practised,  as  in  opium  cultivation, 
the  weevils  and  grasshoppers  both  being  captured  or  drowned.  Trans- 
planted tobacco  has  been  preserved  by  spraying  the  plants  with  lead 
arseniate  and  by  dipping  the  seedlings  before  transplanting  in  the  mixture 
of  lead  arseniate  and  water.  These  plants  are  then  poisonous  and  destroy 
the  grasshoppers  on  a  large  scale. 

In  the  case  of  maize,  sorghum,  cane,  and  similar  crops,  dropping  lime 
and  lead  arseniate  mixture  into  the  heart  of  each  plant  is  also  effective 
and  even  dry  mould  has  a  good  effect,  the  beetles  then  not  eating  the 
delicate  inner  shoot  of  the  growing  plant. 

The  practice  of  burning  rob  lands  has  possibly  some  Value  in  the 
destruction  of  these  beetles  which  are  hiding  in  the  soil  and  would 
destroy  the  seedlings.  Generally  speaking  it  is  advisable,  whenever 
possible,  to  sow  a  trap  crop  (n*  provide  some  alternative  food  for  both 
weevils  and  grasshoppers  ;  this  cannot  of  course  be  done  after  the  crop 
is  uij  and  is  being  injured,  but  the  insects  can  be  anticipated  in  the 
following  season  if  this  precaution  is  adopted  in  time.  Wherever 
grasshoppers  are  known  to  be  abundant^  they  should  be  swept  up  about  the 


Fig.  265. 
The  large  Ground  Grasshopiier. 
(Magnified  twice.) 


tu 


LOCUSTS,    HOPPERSj    SURFACE   BEETLES,   ETC* 


time  the  croiis  are  sown,  together  with  those  in  neig-hbouring  strips  of 
grass.     If  nothing   else   can   be  done   for  the  weevils,  they   should  be 


Fig.  266. 
The  Big  CricJcet. 


provided  with  food,  even  if  it  be  only  heaps  of  green  fodder  laid  about  the 
fields  ;  large  numbers  can  be  captured  in  this  manner,  and  the  ingenuity 
of  the  ryot  is  quite  equal  to  finding  out  the  most  satisfactory  substance 
for  this  purpose. 


Crickets  and  Root  Insects. 

Many  insects  live  in  the  ground  forming  burrows  which  ramify 
below  the  surface  and  open  at  one  or  more  points.  These  are  principally 
crickets,  insects  which  are  closely  allied  to  the  grasshoppers  but  live 
below  groujid. 

Many  species  occur  in  India  whose  distribution  is  not  yet  accurately 

ascertained.  Only  the  larger 
burrowing  species  are  known  to 
be  injurious,  possibly  because 
the  harm  done  by  the  smaller 
species  is  not  attributed  to  the 
right  cause.  These  insects  make 
burrows  which  descend  to  some 
distance  into  the  soil,  always  with 
openings  at  the  surface ;  the 
nature  of  the  soil,  and  the  height 
of  the  sub-soil  water  exercise  an 
influence  on  the  depth  o*^  the 
burrow ;  the  distribution  of 
the  various  species  appears  to 
be  limited  by  the  occurrence 
of  the  particular  soils   they  need.     They   descend  deeper  into  the  soil 


Fig.  267. 

The  Digger  Wasp  that  preys  upon  the  Big 

Cricket. 


CRICKETS.  225 

in  hot  dry  weather,  coming  np  in  the  rains,  either  owing  to  the  rise  of  the 
soil  water  or  because  the  surface  is  tlien  moist  and  cool. 

The  life  histories  of  the  Indian  species  have  not  been  investigated 
but  are  probably  similar  to  those  of  other  species.  In  the  group  in 
general,  eggs  arc  laid  in  a  central  chamber  in  the  ground,  a  large  number 
of  small  round  egg's  being  deposited  in  a  mass  and  cared  for  by  the 
parent.  The  young  that  hatch  are  active  and  sooner  or  later  start  their 
own  burrows ;  they  pass  through  the  usual  moults.  The  food  is  largely 
vegetable  but  not  universally  so,  and  it  is  probable  that  certain  species 
are  mainly  or  wholly  insectivorous,  driving  their  burrows  through  the 
soil  in  search  of  the  insects.     The   large  brown   cricket  ^   (fig.  266)  is 


Fig.  268. 
The  Black-headed  Cricket. 


herbivorous,  making  very  large  and  extensive  burrows ;  it  comes  up  at 
night,  cuts  off  jjlants,  and  descends  with  them  to  its  burrow.  This 
species  grows  to  a  great  size  and  is  common  in  Bengal,  Eihar,  Assam, 
and  Burma.  In  the  rains  it  is  driven  up  out  of  its  burrows  and  the 
crows  then  destroy  a  large  number.  This  insect  is  also  preyed  upon  by  a 
metallic  green  Digger  Wasp  (fig.  267),  which  stings  it,  lays  an  egg  on  it 
and  buries  it  in  its  own  burrow.  In  spite  of  this  cheek  the  insect  is  a 
common  field  and  garden  pest.     Another  smaller  brown  species  ^  with  a 

^     51.  Brachytrypes  achatinus.    StoU.     (Gryllidse.) 
«  272.  Gryllodes  m^lanocephahis,     Serv.     (Gryllidse.) 


2^6 


LOCUSTS,   IIOPPEBS,    SURFACE   BEETLES,   ETC. 


'^ 


black  head  is  reported  io  be  destructive  to  sorghum  in  Upper  Sind  and 

to  crops  in  Shahpur,  Punjab  (fig.  268). 

A   widely  distributed  species   is    the    two-spotted   cricket,^   a   black 

insect  with  a  yellow  spot  on   each  wing  (fig.  260).     It  occurs  in  various 

parts  of  India  and  has  been  found  attacking  a  variety  of  crops. 

In  addition  to  the  injury  done  by  cutting  plants,  these  insects  are  also 

injurious  to  the  roots,  cutting 
through  the  roots  in  the  course 
of  making  their  burrows.  In 
the  rains,  when  their  burrows 
are  near  the  surface,  this  form 
of  damage  may  be  extensive. 

The  Mole  Cricket  ^  is 
particiilarly  injurious  in  this 
connection,  though  there  is 
some  reason  to  believe  it  is 
useful  in  destroying  insects, 
and  that  it  injures  the  plants 
only  when  seeking  for  pests. 
This  insect  is  noticeable  for 
the  beautifully  adapted  fore- 
legs and  prothorax,  the  former 
broad  and  toothed  for  digging, 
the  latter  round  and  hard  for 
forcing  through  the  soil ;  the 
abdomen  is  peculiarly  soft. 
This  is  a  common  insect,  often 


Fig.  269. 
The  Two-spotted  Cricket.     {Natural  size.) 


found  at  night  in  houses,  drawn  there  by  the  lights. 


Fio.  270. 
The  Mole  Cricket. 


» 185.  Liogryllus  Umaculatus.     deG.     (Gryllidae.) 
2  260.  Gri/llofalfa  africana,     PaL  B.     (GryllidiB.) 


THE    BIIETIWA.  227 

Another  fovmidabln  bnvrowino"  insect  is  not  strictly  a  cricket,  but 
placed  in  the  next  family  ;  it  is  known  in  Behar  as  the  hJierwa}  This 
species  makes  burrows  in  the  soil,  usually  near  rivers  and  streams ;  the 
young"  are  similar  to  the  full  grown  insects  but  not  winged ;  the 
appearance  of  the  winged  insect  with  its  most   formidable  jaws  is  most 


Fiff.  271. 
The  Bhertva. 

striking.  This  insect  has  been  reported  as  injurious  to  the  roots  of 
plants  from  several  districts  of  India,  cutting  through  the  roots  of  crops 
in  its  search  for  insects.  Normally  it  lives  near  running  water  and  is 
not  harmful,  but  exceptionally  it  infests  fields  and  does  much  injury  to 
valuable  crops  such  as  tobacco.  Its  distribution  is  limited,  Assam  and 
Behar  being  the  localities  most  infested,  biit  it  has  also  been  found  in  a 
few  widely  separated  localities  in  India. 

Burrowing  crickets  are  extremely  difficult  insects  to  check,  no  good 
method  of  destroying  them  having  yet  been  found.  Species  that  eat 
crop  plants  can  be  poisoned,  the  attacked  crops  being  sprayed  with  lead 
arseniate.  The  crickets  take  the  poisoned  food  to  their  burrows  and  are 
there  killed.  This  is  effective  and  simple,  a  great  diminution  in  their 
numbers  promptly  taking  place.  Flooding  out  is  possible  under  certain 
circumstances  and  is  the  most  radical  method,  the  crickets  being  driven 
to  the  surface  and  killed  by  crows  and  other  birds.  Digging  the  crickets 
out  is  a  slow  and  laborious  method,  but  the  only  one  available  in  some  cases. 

These  insects  should  not  be  confused  with  the  common  insects 
which  live  on  the  surface  of  the  ground  and  never  burrow;  the  group 
is  a  large  one  and  only  the  burrowing  species  are  really  harmful. 

*  170,   ScMzodactylns  monsiruosus.     Dr.     (Locnstidffi.) 


eas 


LOCUSTS,    HOPPERS,    SURFACE    BEETLES,    ETC. 


Termites. 

A  group  of  social  insects,  commonly  termed  white-ants,  wliicli  live  in 
nests  usually  made  in  the  ground.  Structurally  there  is  no  relationship 
between  the  termites,  wliich  are  Neuropera,  and  the  ants,  which  are 
St/menoptera ;  in  their  habits  there  is  a  close  resemblance,  with  clear 
distinctions.     Termites  shun  light  and  never  willingly  expose  themselves 


Fig.  272. 
Wingless  Queen,  after  return  to  rest,  the  ahdomen  distended  icith  eggs. 

to  it.  The  nest  is  usually  imderground  and  from  it  passages  run 
tlirough  the  soil  to  trees,  buildings,  etc.  The  nest  often  projects  above 
the  ground  and  is  made  of  chewed  vegetable  fibre ;  it  contains  many 
chambers  and  passages.  Within  the  nest  the  sexually  mature  indivi- 
duals live,  the  most  important  of  which  is  the  queen  who  produces  tlie 
eg-gs.  A  colony  of  termites  usually  consists  of  one  or  more  fully  deve- 
loped queens,  one  or  more  imperfectly  developed  queens,  and  a  larger  or 
smaller  number  of  males  :  males  and  females  alone  are  winged  at  any 
time.  The  larger  part  of  the  colony  consists  of  smaller  undeveloped 
insects,  termed  workers  or  soldiers,  which  never  become  winged  or  sexually 
mature.     These  leave   the   nest   and   collect  food  for  the  whole  colony. 

Unless  the  actual  nest  is 
found,  only  workers  and 
soldiers  are  seen,  and  it 
is  these  which  destroy 
houses,  eat  crops  and 
damage  trees.  The  nest 
may  be  a  long  distance 
from  the  scene  of  destruc- 
tion, the  termites  com- 
municating- with  the  nest 
by  means  of  a  covered 
passage  or  a  tunnel. 
At  certain  times  of  the  year,  enormous  numbers  of  winged  termites 


Fig.  273. 
Winged  Queen  Termite. 


I'ERMlTlfiS. 


it^ 


come  out  of  tlic  nests ;  these  fly  for  a  short  time  and  then  lose  their  wings. 
They  are  full-grown  males  and  females  but  they  are  not  fully  developed. 
The  greater  number,  if  not  all,  of  these  perish,  the  wings  falling  off  very 
readily  and  the  insects  being  eaten  by  their  numerous  enemies. 

The  food  of  the  termites  consists  of  vegetable  matter,  normally  of 
dead  dry  timber,  but  also  of  living  plant  tissue.  It  is  still  an  unsettled 
point  whether  all  termites  will  attack  a  sound  healthy  living  plant ; 
they  will  attack  unhealthy  living  plant  tissue,  e.ff.,  a  cut  sugarcane,  and 
it  is  certain  that  some  will  actually  eat  a  sound  healthy  plant.  In 
general  the  termites  are  injurious  in  buildings,  where  they  utterly  des- 
troy wood,  leather,  paper  and  similar  materials.  They  also  attack  mango- 
trees  in  parts  of  Bombay  and  the  Central  Provinces ;  the  chilli  crop  of 
Gujarat  is  much  attacked,  as  also  is  sugarcane,  wheat,  ground-nut  and 
other  crops  in  many  parts  of  India.  Exceptionally  other  crops  are 
attacked,  often  when  in  the  rainy  season  the  ants  are  driven  up  by  the  high 
level  of  the  soil  water  and  have  to  find  food  close  to  the  surface  and  not 
in  their  usual  haunts. 

Termites  are  rarely  seen  to  be  attacking  a  plant  or  a  house  until 
it  is  too  late  to  take 
steps  against  them ; 
they  make  a  tunnel 
from  their  nest  to  the 
object  on  which  they 
wish  to  feed.  Should 
they  have  to  cross  an 
open  space  or  go  up 
a  wall,  they  make 
a  covered  way.  Having 
reached  their  objective 
they  eat  into  it,  remov- 
ing the  tissue  and  leav- 
ing only  a  shell. 

The  treatment  of  white-ants  depends  upon  the  circumstances  of  each 
case.     The  following  methods  are  applicable  in  special  cases : — 

(1)  If  a  field  is  infested  with  white-ants,  search  for  the  nest,  dig  it 
out  and  burn  it,  taking  especial  care  to  destroy  any  large  individuals 
found  in  it  which  may  be  queens. 

(2)  If  the  nest  is  found  but  cannot  be  dug  out,  pour  in  carbon 
bisulphide,  kerosene,  sanitary  fluid,  or  even  abundance  of  hot  water. 
This  will  destroy  the  nest  and  if  the  queens  arc  killed  the  colony  will 
be  destroyed. 


Fia.  274. 

young  Termites  which  loill  become  queens. 

{3Iagnified.) 


^^0  LOCUSTS,  HOPPERS,    SUllPACE    BEETLES,    fil^C. 

['6)  AVliere  white-ants  are  prevalent,  tlie  -woodwork  of  a  house 
can  be  protected  by  a  liberal  application  oi:  any  form  of  arsenic  to  the 
door-frames,  Avindow-frames,  wooden  pillars  or  any  exposed  wood,  as 
well  as  to  the  floors  w4iere  this  is  possible.  Several  forms  of  arsenic 
are  procurable  in  the  bazaars  (white  arsenic,  sambul,  somal,  sanha,  etc, 
yellow   arsenic,    lartal,    etc.),   which  can  be  ground  up  very  fine,  mixed 

with  water  and   poured    on.     If   the 

floors   of    all   buildings   were   treated 

with    a    solution    of    white     arsenic 

(formula  No.  14)  before  the  top  layer 

is  put  on,  no  white-ants  would  come 

up   through   the    floor   at    any    time. 

Termites  will  not  oat  through  anything 

impregnated    with    arsenic    and    will 

leave    their   tunnels    if   a  solution   of 

Fia.  275.  arsenic   comes    near.     In   these    cases 

Worker  Termites  of  two  hinds  helonffing       ,,  nnfdrlp    walk    in 

to  one  nest.      (Magnified.)  ^^^^7    ^^J    ^^^^    "P    OUtSlQe    wailS    in 

their  covered  ways,  and  will  then  enter 
the  building  if  possible.     No  application  of  arsenic  will  check  this. 

(4)  If  a  house  is  infested  with  white-ants  little  can  be  done.  If 
their  tunnels  or  entrances  can  be  found,  this  can  be  destroyed  and  the 
places  treated  with  arsenic.  If  they  have  a  nest  outside  and  come  into 
the  house,  their  entrances  to  the  house  should  be  searched  out.  Fumi- 
gation with  hydrocyanic  acid  or  carbon  bisulphide  is  as  fatal  to  termites 
as  to  all  other  insects,  and  where  possible  every  infested  building  should 
be  fumigated,  search  made  for  the  termites^  tunnels,  and  their  future 
entrance  prevented  by  the  use  of  arsenic. 

(5)  In  fields  infested  with  termites,  crops 'are  occasionally  attacked, 
especially  sugarcane,  wheat  and  ground-nut.  If  the  nest  cannot  be  found, 
the  termites  can  be  discouraged  before  the  crop  is  planted,  by  cultiva- 
tion* Such  crops  as  sugarcane,  planted  from  setts,  can  be  protected 
by  the  treatment  of  the  setts.  A  cane  sett  dipped  in  sanitary  fluid, 
fcti-ong  soap  or  copper  sulphate  [tiUia)  solution  or  crude  oil  emulsion, 
Will  not  usually  be  attacked  by  white-ants.  This  is  a  very  simple  and 
oiitirely  efltective  treatment.  Such  vegetable  substances  as  castor  cake, 
ksafoetida  [Jiing),  dekamali  gum,  etc.,  are  less  effectual  but  still  have 
some  effect  in  deterring  wliil cants. 

Similar  but  less  lasting  results  follow  from  the  impregnation  of 
the  irrigation  water  tvitli  small  cpiantities  of  poisons.  It  is  necessary 
to  use  those  which  will  have  no  permanent  effect  on  the  soil  or  crop. 
Crude  oil  emulsion,  sanitary  fluid,  kerosene  oil^  pure  or  in  emulsion,  are 


TERMITES. 


23l 


effectual  if  iutroduced  in  small  quantities  to  the  irrigation  water.  The 
simplest  procedure  is  to  put  a  bag-  of  the  solid^  or  a  tin  of  the  liquid  in 
the  water  channel  so  that  a  small  proportion  is  carried  along-  with  the 
water.  This  is  a  practice  in  Gujarat  where  a  mixture  of  akh  {Calotropis), 
hhunani  (Niger  seed),  nim  cake  {Melia  azaclirachta)  and  castor  cake  is 
placed  in  the  irrigation  channel  in  the  belief  that  the  white-ants  will  not 
attack  the  chillies. 

In  some  cases  nothing  can  be  done  to  discover  or  destroy  the  nests 
of  the  termites,  and  no  certain  method  has  yet  been  found  of  driving 
away  the  pest.  Good  results  have  been  obtained  with  a  top  dressing  of 
manure,  but  the  best  application  has  not  yet  been  found  nor  have  the 
results  been  suiBciently  vmiform  to  give  reliable  methods.  It  is  probable 
that  methods  based  on  this  or  a  similar  principle  will  prove  to  be  effectual 
in  temporarily  checking  the  ravages  of  white-ants  in  growing  crops  and 
we  may  hope  eventually  to  be  able  to  free  land  from  termites  wholly  or 
for  long  periods. 

(6)  Trees  that  are  infested  with  white-ants  can  be  temporarily  cured 
by  the  application  of  kerosene  to  the  bark,  or  of  kerosene  emulsion, 
tobacco  decoction,  soap  solution,  etc.,  to  the  roots.  In  Gujarat  mango- 
trees  are  painted  with  red  ochre  (oxide  of  iron)  called  geru^  to  deter 
white-ants  from  attacking  the  trunks.  Good  results  are  reported  from 
the  Central  Provinces  in  the  treatment  of  white-ant-infested  trees 
with  Gondal  fluid,  and  better  results  have  recently  been  obtained  with 
sanitary  fluid. 

(7)  Termites  are  attracted  by  farmyard  or  stable  manure  that  is  dry 
or  insufficiently  rotted.  The  digging  into  the  ground  of  improperly 
prepared  farmyard  manure  is  a  source  of  white-ant  attacks^  the  insects 
coming  first  to  feed  on  the  manure  and  when  that  is  exhausted  attacking 
the  roots  of  plants.  When  termites  are  prevalent  the  greatest  care  should 
be  taken  to  apply  only  Avell  rotted  manure. 

Injurious  Ants. 

At  least  one  species  of  true  ant  is  known  to  attack  healthy  living 
plants  both  in  Ceylon  and  India.  This  is  the  common  blind  brown  ant,^ 
of  which  the  enormous  male,  as  large  as  and  similar  to  a  wasp,  comes 
into  houses  at  night,  attracted  by  the  light.^  The  nest  is  underground, 
the  workers  behaving  like  termites  and  tunnelling  through  the  soil  to 
the  roots  of  plants.     We  have  been  able  to  confirm  the  observations  of 

^  221.     Dorylus  orUntalis.     VVestw.     (FormicidEe.) 
*  See  figures  54*53  of  D.  Idliatus. 


232 


LOCUSTS,    HOPPERS,    SURFACE    BEETLES,    ETC* 


Mr.  E.  E.  Greeu  in  Ceylon  that  the  workers  actually  eat  sound  healthy 
plant  tissue.     Cauliflowers,  cabbages,  artichokes  and  other  vegetables  are 

attacked  just  below  the  soil  and  completely 
destroyed.  As  these  ants  are  usually  carni- 
vorous the  habit  is  an  exception.  In  the  case 
observed,  the  addition  of  a  small  quantity  of 
crude  oil  emulsion  to  the  irrigation  water  drove 
them  away. 

A  second  injurious  ant  is  the  harvesting 
ant,^  which  gathers  seeds  especially  of  kangni 
{Setaria  italica)  in  the  galleries  of  its  nest. 
This  is  a  moderately  large  deep  brown  and 
black  ant,  which  makes  extensive  nests  in  the 
soil ;  in  the  Punjab  these  nests  are  shallow  and 
easily  dug  out ;  other  observers  in  India  state 
that  the  nests  are  very  deej),  and  this  depends 
probably  upon  the  nature  of  the  soil.  The 
worker  ants  bring  the  seeds  one  by  one  to 
the  nest  and  store  them  in  granaries.  As  much 
as  a  pint  of  seed  may  be  found  in  a  single 
large  nest,  and  as  the  nests  are  in  some  cases 
numerous,  a  considerable  quantity  of  seed  may 
be  destroyed.  The  nests  are  readily  traced  and 
may  be  dug  out ;  the  application  of  hot  water  destroys  the  insects,  and 
the  mere  filling  of  the  nest  with  water  will  be  sufficient  to  drive  out  the 
occupants. 


Fig.  276. 

Brown  Ant  worJcers. 

{Magnified  and  natural  size.) 


262.     Soloomyrmex  scabriceps,     Mayr.     (Formicidse.) 


CHAPTER   XVlll. 


T 


SUCKING     INSECTS. 

HE  distinguishing  character  with  these  insects  is  that  they  suck  the 
juice  of  plants.     They  are  Uemiptera  marked  by  the  presence  o£ 

the  suctorial  proboscis.  For  such 
pests  we  must  as  a  rule  use  special 
remedies. 

Sucking  insects  include  practi- 
cally two  large  classes  with  inter- 
mediates; there  are  the  active  Plant 
Bugs  which  run  about  the  plants 
and  suck  any  part  that  attracts 
them ;  there  are  also  the  Scale 
Insects  and  other  "  Plant  Para- 
sites ^^^  which  fix  themselves  down 
and  never  move.  The  former  may 
leave  no  trace  of  their  work, 
simply  inserting  their  proboscis 
and  feeding  where    they  will ;   the 

Fig.  277.  latter  are  fixed  and  local.     Between 

The  Sorghum  Bug.  (3IagniJled.)  ^^^    ^^^    ^^.^    ^j^^  ^^^^^    I'^g^   ^l^i^^, 

behave  as  the  plant  parasites  but 
share  the  mobility  of  the  plant 
buo-s.  This  is  a  fundamental  dis- 
tinction  when  one  regards  the 
insects  from  the  economic  point  of 
view,  and  entirely  alters  the  charac- 
ter of  the  treatment  possible  for 
each  form  of  disease. 


Plant  Bugs. 

Among  the  occasional  pests  of 
Indian  crops,  the  plant  bugs  are 
of  common  occurrence,  doing  in 
the  aggregate  a  considerable 
amount  of  harm  which  very  rarely 
becomes  apparent.  These  insects 
live  upon  plants,  sucking  the  juice 


k 

^ 

^^^im 

W{ 

Pig.  278. 
The  Fainted  Bug.  {Magnified.) 


M 


SUCilNG   INSECTS. 


Fia.  279. 
Sucking  mouth-parts  of  Hemip- 
tera  ;  the  tipper  one  has  the 
curved  Leak  of  the  predaceous, 
the  lotver  that  of  the  herhivor- 
ous  hugs. 


from  the  leaves,  the  stem  or  the  fruit ;  many  species  are  known  in 
jung-les  and  waste  lands,  a  few  of  which  attack  crops  or  garden  plants. 
The  Red  Bug  and  the  Dusky  Bug  of  cotton  (page  104),  the  Maize  Fly 

and  Cane  Fly  (page  134),  and  the  Rice 
Bug  (page  116)  are  examples  of  plant  bugs 
which  attack  only  specific  crops  and  are 
special  pests.  A  number  of  other  species 
attack  crops  occasionally,  though  feeding 
habitually  upon  wild  plants  and  only  enter- 
ing* the  crops  when  they  have  become 
exceptionally  abundant. 

The  life  history  varies  with  the  sj)ecies. 
Eggs  are  laid  on  the  plant  or  on  the  ground, 
the  little  bugs  that  hatch  resembling  their 
parents  in  general  form.  Bug  eggs  are 
easily  recognisable,  being  laid  in  little 
clusters  on  the  leaves  in  many  cases ;  the 
egg's  are  often  cylindrical  with  neat  lids 
that  open  when  the  bugs  emerge.  There 
are  a  number  of  moults,  the  wings  appear- 
ing at  the  penultimate  one.  The  bug  extracts  food  from  the  plants  by 
means  of  the  beak,  a  slender  tube  provided  with  sharp  lancet-like  instru- 
ments ;  the  end  of  the  tube  is  applied  to  the  plant ;  the  lancets  work  up 
and  down  till  they  pierce  the  tissues  and  the 
sap  is  withdrawn  by  suction.  After  feed- 
ing, the  bug  withdraws  the  lancets  and 
moves  on. 

Plant  bugs  form  a  large  group  with  very 
varied  habits  and  very  diverse  form.  They 
are  in  all  cases  recognisable  by  the  beak,  a 
straight  sharp  tube  which  extends  from  the 
head  along  the  lower  side  of  the  body. 

Other  bugs  that  feed  upon  the  juice  of 
insects  are  predaceous,  having  a  poisonous 
bite.  One  of  the  larger  predaceous  bugs 
comes  into  houses  at  night,  attracted  by 
lights,  and  if  handled,  inflicts  a  very  painful 
l)ite.  These  predaceous  bugs  can  generally 
be  knoAvn  at  once  hj  the  form  of  the  beak,  which  is  short  and  curved ; 
whilst  in  the  plant  bugs  it  is  long  and  extends  straight  between  the 
legs  (see  fig.  279).     This  is  not  invariable  as  some  of  the  true  plant  bugs 


Fig.  280. 

The  Cinchona  Biif/,  almost  ideri' 

tical  with  the   Betel  Vine  Bug. 

(Maguijied.)    {From  Distant.) 


I'tA^T    BtGS. 


33S 


are  predaceous  on  occasion;  but  practically  any  bug  with  a  curved  beak  is 
predaceous  and  therefore  useful.  It  is  unnecessary  to  mention  a  large 
niTmber  of  species  of  bugs,  the  examples  dealt  with  above  being  sufficient. 
The  mosquito  blight  of  tea  is  perhaps  the  best  known  in  India.  Coffee 
berries  in  the  Nilgiris  are  sucked 
by  a  small  brightly  coloured 
plant  bug^  which  is  common 
also  in  Ceylon.  The  potato 
plant  is  the  favourite  food-plant 
of  the  Green  Bug/  a  widely  dis- 
tributed pest  (fig.  190,  page  168). 
Mustard  and  rape  are  the  food- 
plants  of  the  Painted  Bug/  a 
small  brightly  coloured  species 
very  abundant  in  the  plains 
(fig.  278).  Maize,  sorghum  and 
millets  are  found  to  harbour  a 
bug,*  coloured  in  grey,  brown 
and  black,  which  infests  the 
heads  but  does  no  harm  (fig. 
277).  A  closely  similar  species  '" 
with  sharp  spines  on  the  edges 
of  the  thorax  is  common  in  the 
crops  but  is  apparently  wholly 
predaceous. 

The  betel  vine  is  infested  with  a  slender  reddish  bug',"  which  flies  from 
leaf  to  leaf  and  feeds  by  sucking  the  epidermis  on  the  lower  side.  Where 
it  sucks,  a  spot  is  formed  which  in  time  decays  and  spoils  the  leaf.  This 
is  a  more  serious  pest,  the  loss  to  the  crop  being  a  large  one  in  many 
cases.  In  Lower  Bengal  the  Giant  Red  Bug"  is  believed  to  be  a  pest, 
probably  on  account  of  its  very  vivid  colouring,  but  it  is  not  known 
seriously  to  injure  any  crop. 

A  small  greenish  bug  is  commonly  found  upon  the  heads  of  the  cliolam 
[sorghum)  and  cumbu  [bajra]  in  South  India,  sucking  the  milky  grain 
(fig.  282) .  This  is  not  an  unusual  form  of  injury,  but  it  is  rarely  reported  ; 
in  parts  of   South  India  it  appears  to  be  particularly  common  and  the 

^  207.  Antestia  cruciata,     F.     (PentatomidEe.) 

2  223.  Nezara  viridula.     L.     (Pentatomidse.) 

^  1G9.  Baffrada  picta.     P.     (Peutatomida;.) 

*  224.  Agonoscelis  nuhila.     P.     (Pentatomidse.) 

^  G.  116.  Cai/theaoiiaJ'urcellafa.     Wolff.     (Peutatomidtc.) 

*  25.  I>isj)hi)ictus  sp.     (CapsidiB.) 

*  1336.  Loliita  grandis.     Gr.     ( Pjrrhocoridse.) 


Pig.  281. 
The  Giant  Bed  Bug.     {From  Distant.) 


236 


SUCKING   INSECTS. 


bug"   is   a   somewhat    serious    occasional    pest.^     Another    small    dusky 

bug  ^  is  reported  as  a  pest ;  this 
is  closely  allied  to  the  notori- 
ous chinch  bug-  of  the  United 
States,  but  there  is  no  accurate 
record  of  its  being  a  serious  pest 
in  India  (fig.  284).  A  peculiar 
form  of  injury  is  caused  by  bugs 
which  gather  on  the  threshing 
floor  and  suck  out  the  seeds  of 
sesamum  and  other  oil  crops. 
The  principal  of  these  bugs  is  a 
small  brownish  insect/  common 
in  the  plains ;  it  also  attacks 
the  seed  on  the  growing  plant 
and  may  be  reckoned  a  casual 
pest  to  oil  seeds  in  general 
(fig.  285). 

Other   species   have   been    re- 
corded   as    injuring    crops,    but 

cannot  probably  rank  as  pests  in  the  broadest  sense  of  the  word. 

The  method  of  capturing  the  Red  Cotton  Bug  (page  106)  is  applicable 

to  many  other  bugs,  which  are  easily  collected 

by  hand  in  the  crops.     If  this  is  done  in  good 

time  no  harm  results,  and  it  is  only  rarely, 

when  favourable  conditions  occur  and  nothing 

is  done  to  check  them,  that  bugs  become  des- 
tructively numerous.     The  betel  vine  grower 

catches  liis   pest  by  hand,  crushing  it  in  a 

folded  leaf  of  the  plant.     In  the  case  of  the 

Painted  Bug  and  similar  insects,  the   eggs 

are  very  easily  collected  and  destroyed,  and 

the  pest   would  be  most  simply  checked  in 

this   manner  if   the   cultivator  was  familiar 

with  them. 

In  special  cases  it  may  be  possible  to  use 

contact  poisons,  as  when  the  heads  of  cholam 

are  dipped  or  wetted  in  kerosene  emulsion  to 


Fig.  282. 
The  Cholam  Bug.     {Magnified.) 


Fig.  283.     ^ 
Another  Grain- Sucking  Bug. 
[Magnified.)     {From  Distant.) 


'  222.  Calocoris  anguntatus.     Leth.     (Capsidse.) 
2  Blissus  gibbus.     F.   (Lygajidie.) 
'  ApJianus  sordidus.     F.    (Lygseidse.) 


PLANT   LTCE. 


237 


FlO.  284. 
The    Indian     Chinch 
Bug,  ImmaUire 

form.    {Magnified.) 
{From  Distant.) 


prevent  the  bug's  from  g-atlieriuG;"  in  them  to  eat  the  young"  g-rain.  As  a 
rule  no  insecticides  can  bo  used  against  tliese  hard  bugs  at  a  sufficient 
strength  to  kill  them,  l)ut  only  to  drive  them  away  or  to  make  the  plant 
distasteful  to  them. 

Green  Fly  and  Plant  Lice  (Aphidae). 

Plants  are  often  found  to  be  covered  with  colonies  of  tiny  black 
or  yellow  insects,  which  cluster  thickly  on  the  leaves 
and  twigs.  Such  plants,  as  a  rule,  have  an  unhealthy 
appearance  and  the  lower  leaves  are  covered  with  a 
sticky  substance.  This  appearance  of  the  leaf  and 
plant  is  a  symptom  of  one  of  the  sucking"  insects 
described  here ;  if  the  little  insects  move  about, 
are  not  covered  with  a  scaly  covering"  and  have  the 
two  little  tubes  projecting  from  the  abdomen  (see 
fig".  286),  then  it  is  safe  to  conclude  that  the  insects 
are  plant  lice,  also  known  as  green  fly  or  aphides. 
The  insects  are  small,  the  largest  not  more  than  one- 
tenth  of  an  inch  long  ;  each  has  three  pairs  of  legs, 
a  sharp  suctorial  beak,  eyes,  and  feelers;  there  are 
also  the  two  short  tubes  or  knobs  which  project  from 

the  upper  surface  of  the  abdomen.     Some  are  winged,  others  un winged. 
The  life  history  of  these  insects  varies  very  much  according"  to  locality, 

climate,  etc.     As  a  rule,  the  colonies  are  composed 

only  of  females  which  may  be  winged  or  unwing-ed, 

and  all  of  which  produce  young  alive,  all  females. 

Males  are  not  found  and  the  young  attain  maturity 

in  a  few  days  from  birth,  when  they  too  bring" 

forth  young.      The  rate   of   reproduction  is  thus 

enormous,  the   colony  increasing  very  rapidly  in 

number.    When  the  colony  is  small,  it  is  found  that 

the  females  are  un  winged ;  later  on  winged  indi^a- 

duals  appear,  the  wings  forming  gradually  as  they 

do  in  other  insects  which  have  no  metamorphosis- 

These  winged  females  fly  from  plant  to  plant  spread- 
ing the  colony  over  a  large  area ;  wherever  they 

settle  down  they  found  a  fresh  colony,  and  the  rate 

of  multiplication  and  spread  becomes  enormous. 

This  occurs  typically  in  the  species  which  are  found  attacking  crops 

in  India,  and  it  is  probable  that  at  particular  seasons  of  the  year,  males 

are    produced   and   a   sexual  generation  found.     The  life  history  of  no 


Pig.  285. 

The       Til-seed      Bug. 

{Magnified.)     {From 

Distant.) 


238 


SUCKING   INSECTS. 


Indian  species  has  been  traced  throng'liont  tlie  yoav,  hut  on  analogy  with 
species  elsewhere,  there  is  probably  an  alternate  generation  on  another 


Fig.  286. 
Winged  and  Wingless  Plant  Lice.     {3IagniJied  twelve  times.) 

food-plant.  These  insects  injure  plants  by  the  enormous  quantity  o£  sap 
they  extract.  They  also  excrete  a  sweet  li(|uid  which,  falUng-  on  the 
leaves  below,  makes  them  sticky  and  shiny ;  this  appearance  on  the  plant 
is  generally  familiar  in  India.  Ants  and  other  insects  are  fond,  of  this 
liquid  and  come  to  the  plants  to  obtain  it ;  ants  obtain  it  direct  from  the 
plant  lice,  and  it  is  well  known  that  some  ants  use  plant  lice  as  we  do 
cows,  not  only  "  milking*  ^^  them  but  preparing  shelters  for  them  and 
caring-  for  them. 

Plant  lice  attack  plants  more  often  in  cloudy  weather.  This  .is 
due  partly  to  the  fact  that  the  winged  insects  fly  in  cloudy  weather  and 
so  spread,  and  partly  to  the  more  unhealthy  condition  of  the  plant. 
As  a  rule,  too,  plant  lice  thrive  in  damp  weather  or  when  a  moist  wind  is 
blowing ;  a  dry  hot  wind  often  kills  them  so  that  their  occurrence  on  the 
crops  is  largely  a  matter  of  climatic  conditions.  These  conditibns  are 
not  as  yet  fully  understood  and  plant  lice  sometimes  thrive  best  in  the 
absence  of  rain.  Not  only  climate,  but  the  condition  of  the  plant 
affect  the  occurrence  of  plant  lice,  and  the  latter  is  a  subject  that  has 
jiot  been  investigated.     Plant  lice  attack  several  crops  in  India  and  are 


APHIDES, 


239 


destvuctivo  to  some  of  them.  The  Cotton  Aphis  is  dealt  with  above 
(pao-e  110).  Other  species  attack  tuv  and  leg-iiminous  plants,^  mustard, 
rape  and  ernciferous  crops,®  sorghum  and  maize,  wheat,  indi^^o,  etc.  All 
are  deslruetive  when  circumstances  are  favourahle,  and  a  Ion";-  spell  oC 
cloudy  weather  will  hrino-  them  out  upon  the  crops. 

An  important  feature  in  these  attacks  is  the  vigour  of  the  plant  ;  a 
strong-  healthy  plant  resists  attack  and  is  less  liable  to  it;  an  exotic 
plant,  not  fidly  acclimatised,  suffers  more  than  a  hardy  indigenous 
variety.  Crops  growing  under  bad  conditions,  with  too  much  moisture  or 
on  exhausted  land,  suffer  far  more  than  the  same  plants  growing  under 
good  conditions.  As  a  rule,  an  attack  of  plant  lice  is  produced  by  these 
causes,  and  only  a  removal  of  them  effects  a  cure. 

The  artificial  remedy  for  plant  lice  is  spraying,  a  perfectly  efficient 
and  simple  business  which  should  be  carried  out  on  experimental  farms. 
It  is  not  at  present  possible  to  introduce  it  into  general  use  and  will  never 
be,  until  the  cultivator  is  able  to  watch  for  his  pests  and  check  them  at 
the  start.  A  field  once  thoroughly  infested  with  aphis  can  be  cured  only 
by  a  considerable  expenditure  in  labour  and  insecticides,  an  expenditure 
exceeding  two  rupees  an  acre  under  the  best  possible  conditions.  The 
actual  destruction  of  the  first  colonies  of  the  plant  lice  by  spraying  is  a 
matter  principally  of  watchfulness,  the  necessary  materials  costing  but 
very  little  ;  but  this  requires  an  intelli- 
gent foresight  and  much  care  in  finding 
and  thoroughly  destroying  the  first  colo- 
nies. As  a  rule  nothing  can  be  done  to 
check  plant  lice  because  the  matter  is 
not  taken  in  time  ;  the  adverse  climatic 
conditions  cannot  be  altered;  the  vigour 
of  the  plant  must  be  maintained  in 
every  possible  way  and  so  far  as  possible 
the  first  colonies  of  plant  lice  destroyed. 

Further  investigation  of  plant  lice  is 
required  to  discover  their  alternative 
food-plants  and  generations,  as  they  live 
only  for  part  of  the  year  on  crops  and 
probably  have  wild  food-plants  at  other 
seasons ;  it  may  be  possible  to  check  them 
by  the  destruction  of  these  food-plants, 
this  being  done  at  a  time  when  tlie  attacked  crop  is  not  growing.     Plant 


a' 

-  -~  i  -^ 

7      -^Si 

!(■■ 

■~  i 

Fia.  2S7. 

Tlie  scale  enclosincf  the  young 
Mealy  Wing.     (3Iuch  magnified.) 


^    83.  Aphis   cardui.     Linn.     (Aphidae.) 
*  162.  Aphis  brassicce,     Jiinu.     (Aphidae.) 


240 


SUCKING    INSECTS. 


lice  have  many  enemies^  wliich  cause  an  enormous  dimintition  in  their 
numbers.  These  insects  are  dealt  with  elsewhere  (page  273).  If  we  could 
be  sure  that  these  enemies  would  attack  the  plant  lice  in  time,  Ave  could 
naturally  check  nearly  every  outbreak,  but  at  present  this  is  not  possible. 
These  beneficial  insects  should  be  g-enerally  familiar  and  on  no  account  be 
destroyed, 

The  Mealy  Wings  (Aleurodidae). 

Small  scale-like  insects  are  frequently  found  upon  plants,  with  small 

whitish  flying  insects  which  look 
like  very  minute  moths.  These 
are  the  insects  known  as  mealy 
wings,  generally  classed  with  the 
scale  insects  and  mealy  bugs,  from 
which  they  are  however  quite 
distinct.  The  young  of  both  are 
much  alike  in  general  appearance, 
but  if  winged  insects  are  found  in 
any  numbers,  the  species  is  almost 
certain  to  belong  to  this  group.  A. 
number  of  species  are  known  in 
India  vipon  a  variety  of  plants,  and 
though  not  common  as  pests  they 
are  found  and  sent  in  for  examina- 
tion occasionally. 

JAfe  History. — The  female  lays 
eggs  upon  the  plant,  the  eggs 
usually  enveloped  in  white  cottony 
material  which  she  places  upon  the 
leaf.  These  eggs  hatch  to  small 
insects  which  walk  about  the  plant. 


Fia.  288. 
Young  Mealy  Wings  in  scales. 


Each  insect  is  very  minute,  scarcely  visible  to  the  naked  eye  ;  it  has  a 
beak  which  it  pushes  into  the  tissues  of  the  plant  in  order  to  extract  the 
sap.  Having  found  a  good  place  it  settles  down  and  remains  there  until 
it  emerges  as  a  flying  insect.  Each  insect  when  settled  down  has  the 
appearance  of  a  small  scale,  not  more  than  one-tenth  of  an  inch  long  ; 
often  they  are  black  or  dark-coloured  Avith  a  fringe  of  white  and  some 
white  down  over  them.  Others  are  brown  or  green,  or  are  transj)arent 
and  not  easily  seen  upon  the  plant.  They  remain  fixed  on  the  plant,  often 
in  large  numbers  together.  The  juice  of  the  plant  is  sucked  out  and  the 
plant  itself  weakened,     The  period  during  which  they  live  thus  varieg 


MEALY    WINGS. 


241 


according-  to  season,  and  otlier  conditions.  When  nearly  I'uH  yroMii  tlie 
insect  rests,  entering-  into  a  condition  similar  to  that  oL'  a  butterfly 
chrysalis.  When  this  is  completed,  a  tiny  Avhite  insect  emerges,  with 
two  pairs  oi*  wing's  hxrge  for  its  size,  Avhich  g-ive  it  the  appearance  of 
a  tiny  moth.  Both  sexes  are  Aving-ed  ;  this  and  the  fact  that  they  have 
four  Avings  distinguishes  them  from  the  very  similar  scale  insects 
[Cocclda)  in  which  the  male  alone  has  two  wings,  the  female  none. 

Having  mated,  the  female  lays  eggs  and  dies. 

Mealy  wings  are  found  upon  a  variety  of  plants  and  there  are  many 
species  in  India.  Two  attack  orange,  one  attacks  sugarcane,  another 
attacks  rose  ;  a  common  one  in  Western  India  attacks  the  mango,  the  leaves 
being  covered  with  the  small  black  scales.  Another  is  found  on  castor,  and 
many  wild  plants  are  infested.  The  group  is  not  fully  known  yet,  and,  though 
not  as  important  as  the  scale  insects,  many  species  remain  to  be  discovered. 

If  the  insects  have  not  yet  reached  the  flying  stage,  they  may  in 
some  cases  be  destroyed  by  cutting  off  the  infested  part  and  burning  it. 
No  other  treatment  is  possible  except  spraying*  insecticides  on  to  them 
to  kill  them.  This  is  cj^uite  simple  if  the  necessary  appliances  are  avail- 
able and  is  described  elsewhere  (Chapter  VII).     The  insecticides  best  for 


Fig.  289. 
The  Clouded  Mealy  Wing.     {^Magnified  six  times) 

use  are  kerosene  emulsion  or  rosin  wash  (made  on  the  spot)  or  criide  oil 
emulsion  or  INIcUoug'aFs  Insecticide  (bought  ready  for  use).  This  is 
the  simplest  treatment  and  one  that  should  be  used  in  all  gardens  or 
orchards  where  fruit-trees  or  valuable  plants  are  grown. 


242 


StICKING    INSECTS. 


Black  Blight. — Plants  infested  with  these  insects  often  have  a  black 
coating  on  their  leaves  commonly  called  "  Black  Blig'ht ";  this  is  often 
mistaken  for  the  real  disease.  This  black  coating  is  the  result  of  the  work 
of  the  insects  ;  they  snck  a  great  quantity  of  juice  from  the  plant  and  in 
turn  a  sweet  fluid  (honey  dew)  drops  from  them  upon  the  leaves  below  ; 
as  this  dries  it  becomes  sticky  and  then  a  mould  {CapnocUmn)  grows  in  it 
Avhich,  being  black,  gives  the  plant  a  black  appearance.  This  mould 
(similar  to  that  which  comes  on  boots,  etc.,  in  the  rains)  does  little  harm 
and  does  not  penetrate  the  tissues  of  the  plant.  The  black  must  be  traced 
to  its  right  cause,  the  insects  ;  when  these  are  killed  the  mould  will  cease. 

Scale  Insects  and  Mealy  Bugs  (Coccidse). 

A  class  of  pests  distinct  from  all  others  are  formed  by  the  insects 
generally  known  as  Scale  Insects  and  Mealy   Bugs.     They  arcj found 


Fig.  290. 
Red-spotted  Scale,     a,  natural  size,  h,  female  scale,  c,  male  scale,  i,  female,  e,  male. 


as  small  scale-like  insects,  usually  thickly  infesting  the  leaves,  twigs  or 
bark  of  the  plants  they  attack.  Many  are  covered  with  distinct  scales, 
formed  of  special  wool-like  niatcriiil  mixed    with   the   cast   skius   uf  the 


SCALE    INSECTS. 


tU 


insect,  itself ;  others  are  covered  in  loose  white  material 
like  cotton  wool  wliich  completely  envelopes  them  and 
gives  them  their  name,  mealy  bugs.  In  some  the 
covering-  takes  the  form  of  thick  opaque  wax,  arranged 
in  more  or  less  regular  plates.  Another  large  division 
^f  has  no  special   covering   but   the   skin   of   the   upper 

rj  surface  is  thickened.     In   nearly  all   species  the  size 

•^  is   not  more  than  one-eighth  of   an   inch,   the  insect 

W  being  flattened  and  closely  attached  to  the  plant.    No 

^^  definite  characters  can  be  given   by  which    to  distin- 

guish these  insects  from  many  others  which  resemble 
them. 

Zife  Histori/. — The  female  produces  very  large 
numbers  of  eggs,  which  may  hatch  at  once  or  remain 
dormant  for  a  long  period.  As  a  rule  these  eggs  are 
produced  slowly  and  accumulate  under  the  body  of 
the  insect  or  in  a  special  egg*  case  attached  to  her 
body.  The  number  of  eggs  is  generally  some  hun- 
dreds, often  thousands.  The  young  that  emerges  is  a 
small  insect,  flattened,  with  three  pairs  of  legs  hidden 
under  the  body,  a  long  suctorial  beak,  and  minute  eyes. 
The  young'  walk  actively  and  may  go  for  some  distance 
in  search  of  a  fresh  food-plant.  Eventually  each  settles 
down,  buries  its  beak  in  the  tissues  of  the  plant  and 
feeds  upon  the  juices.  When  grown  larger,  the  skin 
is  shed  and  the  insect  often  becomes  a  degraded  legless 
creature  hidden  under  its  protective  covering. 
The  females  moult  once 


Fig.  291. 
The  Black  Shield 
Scale. 


more  and  are  then  matu.re. 


incapable  of 
after  the 
though      the 

in  particular 
throuo-hout 


Most      are 
movement 
first    moult, 
mealy   bugs 
remain    active 
life. 

The  male  underg'oes 
two  further  moults  and 
after  passing  through  a 
period  of  rest,  emerges  as 
a  tiny  two-winged  fly, 
so     small     as      to     escape 


Fio.  292. 
Tlic  Black   Shield  Scale,     {Magnified  five  times.) 

r   '^ 


244) 


SUCKING    INSECTS. 


observation.    It  flies  in  search  of  a  female,  mates  and  dies.     Sooner  oi' 
later  the  female  produces  egg-s  in  turn  aud  dies. 


.i%: 


Fia.  293. 
The  Red-sjjulted  Scale  {left)  and  Black  Shield  Scale  (^riffltt). 


The  whole  life  history  may  be  very  short  or  the  adult  female  may 
live  for  many  montlis  before  producing*  egg's. 
In  some  cases  the  egg's  remain  unhatched  for 
a  long  period,  awaiting  favourable  conditions. 
A  curious  feature  of  these  insects  is  the  frequent 
absence  of  males  altogether ;  there  may 
be  none  for  many  generations  and  in  some 
species  no  males  have  yet  been  found.  In 
others  there  are  as  many  or  more  males  than 
females. 

Food-plants. — There  are  many  species  in 
India  which  attack  a  variety  of  plants.  The 
coffee  plant  suffers  from  the  notorious  Brown 
Bug-,^  the  Green  Bug  ^  and  a  Mealy  Bug.'^ 
The  first  of  these  is  scattered  almost  tiirough- 
(tf   Southern   India,  and    ('!iius(\s  a  la,rge  amount 


Fig.  294. 
Scale  Insects  on  a  leaf. 


out  the   coffee  distric 

of    damage.      It    has    been    successfully     treated     by 

*  Lecanium  hemispharicum.     T.  T.  |  ^  Zecaniiim  viride. 

^  Dacliflopius  ciiri.    R. 


spraying, 
Gr. 


and 


MF,AT,Y    BUf!f='. 


24-5 


experiments  show  1hat  spraying'  with   vopin  Avasli  cliocks  tho  iiipocl:  and 

is  profitable. 

The  Green  Bu^-  is  less  widely  scattered  but  appears  to    be    spreading- 

from  the  Pulny  Hills  into    the    Nilg'iris  and  will  probaldy  reach  other 

districts.     Both  of  these  insects  infest  ilie  twigs,  sucking  out  the  juice 

and   gradually  or  quickly   killing    tlie    plant.     The    Coffee    Mealy   Bug 

in  Coorg  infests  tlie  roots,  specially  of  young  plants.     J'^xperimeuts  show 

that  treatment  with  lime   and   sulphur,  aided  by  an  occasional  applica- 
tion    of    insecticide, 

keeps     this   pest    in 

cheek.   Elsewhere    it 

attacks   a  variety  of 

plants,  mostly  garden 

plants. 

The  shade  trees  of 

coffee  in  Mysore  are 

infested  by  the  Green 

Mealy  Scale,i  which 

attacks  certain  trees 

and       destroys     the 

foliage.     The     black 

blight    produced    by 

this  and  allied    spe- 
cies on   coffee   shade 

trees      injures      the 

coffee  and  is  one  of 

the  worst  features  of 
this  pest. 

Another  destructive  species  is  the  Red  Spotted  Scale,^  a  dark- 
coloured  scale  with  a  reddish  centre ;  this  attacks  palms  and  is  injurious 
to  the  betel  palm.  Sugarcane  is  attacked  by  three  species,^  the  mealy 
bug  of  cane  alone  being  widespread.  It  is  most  easily  checked  by  care 
in  the  selection  of  only  clean  setts  for  planting. 

Cotton  is  attacked  by  a  mealy  bug  which  lives  in  the  top 
leaves  of  each  shoot  and  causes  the  shoot  to  twist  and  form  a  gall ; 
it  attacks  only  certain  indigenous  varieties  and  is  known  only  in  Behar. 
Plucking  the  affected  shoots  is  the  simple  and  radical  treatment  for 
this  pest. 

^  Pvlrinaria  jjsiijii.     Maslc.  |  "^  Aspi(^iotii<i  fcn/s.     Asliin. 

•^  T)actylo'pkui  sncehari.     Civil.      (Cano  Mpaly  Bngr.) 
Rtpersia  sacchari.     Gr. 
^clpffJa  Japo)ilc(T.     Maskj 


Fig.  295. 
The  Tea  Meali/  Bit  a. 


246 


SUCKING    INSECTS. 


SppcI  potatoes  in  parts  of  Boni^'al  nvo  attanlcod  by  a  small  moa^y 
bug  vvhicli  infests  them  during'  the  rains  and  causes  them  to  rot.  This 
is  not  a  field  pest  but  attacks  the  stored  potatoes. 

Many  species  are  reported  as  attacldug  tea  iu  India  and  others  are 

common  on  fruit  trees  and 
garden  plants.  The  latter  are 
rarely  destructive  but  occa- 
sionally spoil  the  appearance 
of  good  plants  by  producing 
"black-blight." 

A  destructive  species  ^ 
attacks  the  mulberry,  infest- 
ing the  ends  of  the  growing 
shoots  and  causing  them  to 
become  twisted.  This  pest 
is  a  serious  one  in  mulberry 
plantations,  unless  the  plants 
are  vigorous  enough  to 
outgrow  it.  A  striking  case 
of  mealy  bug  attack  is  found 
in  the  very  large  white 
mealy  bug  ^  which  comes  up 
from  the  soil  during  the  cold 
weather  and  first  weeks  of 
the  warm  weather  ;  immense 
numbers  of  half-grown 
females  come  up,  feeding  upon  the  bushes  and  trees,  gradually 
walking  up  the  bark  until  they  reach  the  ends  of  the  branches. 
They  become  very  large,  conspicuous  white  masses  of  them  clustering  on 
the  end  of  the  twigs.  The  males  emerge  from  smaller  scales  and  fly 
about  among  the  branches.  This  is  one  of  the  largest  species  of  mealy 
bug  found,  and  the  male  is  very  large  in  comparison  to  the  males  of  most 
insects  of  this  family.  It  is  injurious  to  occasional  plants  but  is 
very  easily  killed  with  sanitary  fluid  or  other  contact  poisons.  Its 
food-plants  are  large  trees  and  it  is  not  injurious  where  it  can  reach 
these.  ^ 

When  scale  insects  are  found,  the  simplest  method  is  to  cut 
off  and  burn  the  infested  branch.  The  insects  cannot  escape  by 
flying  and  are  easily  destroyed.  In  coffee  and  tea  plantations  it  is 
important   to   watch  for    them  and   check   them    at   once,  and  this  is 


Fig.  296. 

Scale  Insect. 

The  male  scale  is  the  small  narroiu  one,  with  one 

cast  shin,  the  female  larger,  with  two. 


Dacti/lopius  hromelice.    Bouphe. 


'  Monophlebus  spp. 


MEALY    BUf!R. 


247 


noeessary  ali^o  on  hmi  ivoofi.  Tlio  only  olliov  Rim])lo  vomody  is  \o 
spray  them  willi  an  insecticide. 
Kerosene  emulsion  is  a  g-ood 
mixture  for  the  softer  woolly 
ones ;  rosin  wash  for  the  hard 
scale-bearing-  species.  Crude  oil 
emulsion  or  McDougaFs  insecti- 
cide are  also  good  mixtures 
and  can  be  obtained  ready 
made.  The  insecticide  must  be 
applied  with  some  form  of 
spraying    machine,    not     simply 

thrown   on  with  a  syringe.     In 

Fig.  297. 
gardens      where      many      plants  ^^^^^  ^^^^^^  ^.^^^^    (ATa^niJied.) 

are    grown,    the     use    of    such 

insecticides  is  imperative  if  valuable  plants  are  infested. 


V 


Part  IV. 


OTHER    IMPORTANT    INSECTS. 


CHAPTER  XIX. 


INSECTS  INFESTING  GRAIN. 

A  NUMBER  o£  destructive  insects  feed  upon  dry   o^raiii  ilour,  seeds, 
pulse    and   other    dry    food-stuffs,    occurring    in    great    quantity 

wherever  these  are  stored  in  bulk 
and  worldng  a  very  large  aggregate 
amount  of  destruction.  They  are 
common  also  throughout  the  villages 
of  India,  where  special  means  of 
storage  are  used  to  exclude  them, 
not  always  successfully. 

They     belong    to    two    orders, 

the    beetles    and     the    moths,   the 

Fig.  298.  former  being    the   more    abundant. 

Rice  Weevil  Gmh.    {Magnified.)  ^^  extensive  investigation  has  ever 

been  conducted  into  these  pests  in  India  and  the  available  information 

has  been  gleaned  from  reports  or  discovered  in  chance  investigation. 

The  Rice  Weevil.i 

A  small  dark-coloured  weevil,  about  one-eighth  of  an  inch  long  with 
a  prominent  curved  snout.  It  lays 
its  eggs  on  rice,  corn,  wheat  and 
other  grains,  in  little  indentations 
made  with  its  jaws ;  the  larvae  eat 
into  the  grain,  become  full  grown 
there  and  emerge  as  weevils 
after  passing  through  the  pupa 
stage.  The  insect  is  apparently 
abundant  everywhere  in  India, 
and  is  known  throughout  the 
warmer  parts  of  the  world.  It  is 
injurious  to  nearly  all  varieties  of 
grain. 

The  Wheat  Beetle.^ 

The  Wheat  Beetle  has  been 
found  attacking  wheat  and  other 
stored  produce  in    India,  its  larvse 


Fig.  299, 
Rice  Weevil  Pupa.     {Magnified.) 


Calandra  oryzcB.  L,  (Curculionidae.)    |    '  Trogosita  inauritanica.  L.  (Trogositidae.) 


252 


INSrXTS    INFESTING   GUAINT. 


being'  deslnieiivc,  llioimh  nol  living-  aolnally  in  ihe  g>rnin. 

lielieved   to     be 


Fig.  300. 

The  Jiice  Weevil.     {Ma<iiiifiecl.) 


worm  cocoons  in  India 
silkworm  moth.  Its 
larvae  are  very  hairy, 
distinct  in  appearance 
from  those  of  the  preced- 
ing beetles. 

A  dermestid  *  closely 
allied  to  the  last  is 
reported  from  India  in 
wheat.  This  or  the  last 
is  the  insect  found  in 
i^rain  in  Gujarat,  where 
it  is  believed  to  be  of  use 
in  checking  other  grain 


an( 


IS 


The  beelle  is 
carnivorous, 
attacking-  other  insects  found 
in  the  g-ranary. 

The  "Sawtooth  ]ieetle''' 
is  so  called  from  the  toothed 
appearance  of  the  prothorax. 
It  is  found  in  all  stages,  the 
larvae  running  actively  in 
the  grain,  hiding  when 
exposed  to  light.  It  has  been 
recorded  as  destructive  to 
sorghum  and  other  stored 
produce.  This  is  also  a  cos- 
mopolitan i)est.  The  Biscuit 
Beetle,^  a  minute  brown 
insect  found  attacking  bis- 
cuits in  Calcutta,  is  closely 
related  to  the  last  species 
and  belongs  to  a  cosmo- 
politan genus.  The  Leather 
Beetle  ^  is  a  cosmopolitan 
insect  enemy  of  leather  and 
leather  goods  ;  it  attacks  silk- 
destructive    to    stoi-cd     pup;c    of    the 


Fig.  301. 
Rice  Weevil,     {Magnijied.) 


Silvanus  surinamensis. 
'  LcBwopliloeus  pttsillvs. 
Dermestes  vul2')imis.     F. 
JF.iliriostoma  vndvlnla. 


L.     (Cucujidae.) 
F.     (Cucniidse.) 

(Deriiicstidpc.) 
Motscli.     (Dermeetida'.) 


GRAIN    BEETLES. 


Ii53 


Fig.  302. 

The  Wheat  Beetle. 

(Mafjw'Jied.) 


insects,  notably  tlic  Red  Grain  Beetle.     This  belief  is  so  firmly  held  that 

the  derinestid  is  introduced  in  the  «^'rain  infested  witli 

insects  as  a  check  on  them. 

The  Cheroot  Beetle  ^    is   a    small  active    insect, 

whose  larvvB  are  found  principally  in  cheroots  and 

tobacco,  but  also  in  opium,  saffron,  ging-er,  etc.     It 

is   closely    allied    to    a    similar  insect    now  almost 

cosmopolitan,  which  attacks  tobacco  in  all  its  forms 

elsewhere. 

The  two  Red  Grain  Beetles  ^  are  very  common 

in  India,  feeding-  upon  grain,  biscuits,  and  having 

a  great  liking'  for  dried  insects.     Both  are  cosmo- 
politan  and   they    are     disting-uishable    only    with 

some  care. 

The  Areca  Nut  Weevil  '^  is  a  widely 
spread  insect  which  attacks  the  areca  nuts 
and  is  also  a  common  insect  in  old  dry 
cotton  bolls ;  its  larvae  live  in  the  seeds  of 
old  cotton  bolls  left  on  the  plants,  and 
immense  numbers  can  be  bred  from  them. 
Probably  the  insect  has  many  other  foods. 
Finally,  the  notorious  "Cask  Weevil ^^  may 
be  mentioned,  a  species  found  to  attack 
beer  casks  in  India,  not  from  a  taste  for 
the  contents    but    for   the    wood    which  is  its 

natural  food.     This  species  is    the    Sugarcane 
Fig.  303. 
I'he  Biscuit  Beetle. 

Weevil  *  of  the  West  Indies, 
an  insect  attacking  diseased 
canes  and  at  one  time  be- 
lieved to  do  much  harm. 

In  addition  to  the  above 
species,  there  is  a  distinct 
family  which  attacks  pulse. 
These  beetles  lay  their  egg's 
on  the  dried  pulse,  small 
yellow  eggs  very  closely 
resemblinii"      eerlain     scale 


The  S,f> 


'  Lasiodermo  lestacenm.  Daft.    ( Ptinid;L'.) 
2  Triholium  ferni<jineH'm.     F.  and  T. 
Confustim.     D\v.    (Tenebrioniiiie.) 


Fig.  304-. 
Toiilheil  G raiti  Beetle.    Larva  in  the  middle  ; 
pit  pa  OH  the  r  if/hi.     {Mai/nifted.) 

5  ArcEcertis  fasciciilatiis.     De^.     (Antliribida'.) 
*  Xylehurtis  perforcins.     Woll.     (Scol.vtklio.) 


254 


IJJSECTS    INFESTING   GEAIN4 


insects.     The  grub  eats  into  the  seeds,  making  a  neat  cavity  which  just  holds 
the  insect,  and  lives  there  until  pupation  when  it  prepares  an  exit  for  the 


Fig.  305. 

The  Cheroot  Beetle.     Fwpa  on  the  right ;  Larva  in  the  middle.    (Magnified^ 

beetle  by  cutting  a  neat  round  disc,  not  cutting  it  through  but  leaving  it  so 
that  the  beetle  can  escape  easily  (fig.  308).  These  pulse  beetles  are  of 
peculiar  form  and  easily  recognisable.     They  attack  the  common,  pulses 


Fig.  306. 
Larva  and  imago  of  contmon  Leather  Beetle.    (Magnijied.)  ^ 

of  India  in  the  dried  condition  and  have  not  been  found  upon  the  grow- 
ing plant,  as  they  are  elsewhere.     At  least  two  species  ^  are  common  in 

•  Bruchus  chinensis.     iu     (limchi(liu.)j    and  Bruehiis  cmarginaltts.     All.     (Bruchida-.) 


p£a  beetles. 


255 


pulse  and  a  lliird  is  recorded  in  tamarinds.^     Several  wild  species  have 
been  found  and  wild  leg-uminous  plants  are  probably  extensively  attacked. 


Fig.  307. 
The  Red  Beetle.    {Maffiiijied.) 

]\iotlis  are  also  injurious  to  g-rain^  flour  and  similar  products^  and  it  is 


Fig.  308. 

Beans  attacked  by  beetles,  showing  the  holes  of  exit  made  by  the  leetles  and  the 

discs  cut  in  the  sJcin, 

uncertain  as  yet  which  species  are  concerned.     One  small  moth,  known  as 


^  Caryoboms  tjouagra,     F.     (Bi-ucbidie.) 


256 


INSECTS    INFESTING   GllAlN. 


(lie  Aiijoumois  ^  Grain  Moth,  lias  been  fouiid  attacking-  corn.     This  moth 

lays  its  eg'g's  on  the  grain,  the 
larvae  i-ating  straight  in  and 
spending  their  larval  life 
within.  The  moth  is  a  small 
handsome  insect,  found  flying 
in  granaries  and  ware-houses. 
At  least  one  other  ^  moth  is 
common  in  India  on  flour  and 
meal.  The  larva  of  this  species 
is  found  making  silken  web- 
bing to  which  the  meal  becomes 
attached,  the  whole  forming- 
galleries  in  which  the  larva 
lives.  These  peculiar  webbed 
masses  of  meal  or  flour  are 
characteristic  and  easily  seen. 


Fig.  309. 

The  Tamarind  Beetle.     Larra  bfloiv  ;  pujja  on 

the  riyht.     {Mctfjnifitd.) 


Treatment. 

Food-grains,  dried  food-stuffs  and  seeds  of  all  kinds  are  liable  to  the 
attacks  of  these  insects  and  are  sure  to  be  infested  sooner  or  later  if 
precautions  are  not  taken.  The  following  are  the  principal  precautions 
which  should  be  adopted  in  the  preservation 
of  all  seeds,  grain  and  food-stuffs  from  insects. 

(1)  Before  placing  seeds  in  a  godown  or  a 
room  of  any  description,  make  sure  that  it  is 
clean,  and  that  there  is  no  refuse  or  spilt  grain 
in  which  the  insects  could  breed  or  hide. 

(2)  Never  store  seeds  that  are  already 
infested  with  insects  or  that  could  be  harbouring 
o-rain  beetles ;  one  beetle  is  sufficient  to  infect 
the  seeds,  and  the  increase  in  a  few  generations 
of  beetles  will  be  suflficient  to  destroy  the  seeds. 

(3)  Keep  all  grain,  seeds,  etc.,  in  tight 
vessels.  It  is  useless  to  store  grain  in  an  open 
receptacle,  exposed  1o  weevils.  Sooner  or  later 
insects    will    come    to    the   grain   and    lay    eggs 

»  Gelechia  cerealella.  Oliv.  (Tiuelidse./  |    ^  Epheslia  calnritella.  Oliv.  (Pyralidse.) 


Fio.  310. 

The  larfje  I'lilse  Beetle. 

(Maffiiifed.) 


TREATING   GRAIN. 


257 


•  A* 


there.  Either  the  whole  godown  must  be  insect-proof  or  the  seeds  must  be 
kept  in  tight  vessels.  A  bamboo  basket  is  not  insect-proof  unless  well 
plastered  with  mixed  mud  and  cowdung-.  If  there  is  anywhere  a  crack 
larg-e  enough  to  admit  a  grain 
weevil,  the  grain  will  be  spoilt. 

(4)  If  stored  grain  becomes 
infested  with  weevils,  it  must  be 
removed  and  cleaned.  Even  in 
an  air-tight  bottle  or  jar,  weevils 
will  live  and  breed  if  they  are 
put  in  with  the  grain.  If  once 
the  grain  is  infested,  it  must  be 
taken  out  and  cleaned  so  as  to 
separate  the  good  grain  from  the  bad.  Such  grain  before  being  replaced  in 
the  godown  must  be  cleared  of  insects  by  fumigation. 

Seeds  and  grain  can  be  kept  safely  only  in  air-tight  vessels  or  in 
insect-proof  places,  but  this  is  not  sufficient  as  the  grain  when  put 
in  may  be  infested  with  the  eggs  of  grain  beetles.  If  grain  is  stored, 
it  should  be  examined  after  storing  to  make  sure  that  no  insects  are 
breeding  in  it. 

There  is  no  treatment   known  that  will  make  a  seed  proof  against 


Fig.  311. 
The  Gram  Beetle.     {Magnified.) 


\"'%m.-- 

fl 

Ih 

m 

%. 

i 

r 

£  IK  ^ 

':ar 

m 

•• 

«■^ffXUu^ 



Flovr  Moth. 


Fig.  312. 

Caterpillar  ;    cases  of  four  and  tcehling  ;  pztpa  {on  right)  ;  moth. 
{Magnified.) 


weevils  and  not  impair  its  germination  or  food  value.  Seed  cannot  be 
kept  unless  put  away  free  from  infection  and  kept  so.  It  is  easier  to 
keep  seed  free  from  insects  than  it  is  to  be  sure  that,  when  put  away,  it 
is  not  infected ;  the  principal  difficulty  with  the  storage  of  grain  on  any 

8 


258 


INSECTS    INFESTING   GEATN. 


Fig.  I. 


large  scale  is  that^  when  stored,  it  is  already  infected.  Fumiga- 
tion alone  will  ensure  that  the  seed  is 
entirely  free  from  insects  or  insect  eggs  ; 
fumigated  seeds  can  be  safely  stored 
but  are  not  safe  if  improperly  stored; 
if  seed  is  fumigated  to-day,  we  know 
we  can  store  it  as  being  free  from 
weevils,  but  if  we  leave  it  exposed 
for  another  day,  it  may  be  infested 
again . 

The  best  method  of  grain  preserva- 
tion  is  then  to  fumigate  it  and  at  once 
store  it  in  insect-proof  bins  or  jars  or 
boxes,  or  in  an  insect-proof  building. 
A  dry  underground  pit  is  suitable,  if 
properly  insect=proof.  Fumigation  is  a 
process  of  exposing  grain,  seeds,  etc.,  to 

the  fumes  of  carbon  bisulphide  at  a  proper  strength  for  a  definite  period ; 

grain  exposed  to  the  fumes  of  carbon  bisulphide  at  the  rate  of  1  oz.  per 

15  cubic  feet  of  space  for  24  hours  will  be  free  from  all  insects ;  even  the 

eggs  of  the  insects  will  be  killed  and  the  grain  can  be  removed,  the  fumes 

allowed  to  evaporate  and  the  grain  at  once  stored.     Where  large  quantities 

of  grain  are    put  into  a 

godown  till  it  is  full  and 

there    is    no    extra    air 

space,   we    may  use  one 

to  one  and  a  half  lbs.  of 

the  fluid  per  ton  of  grain. 

For  fumigating  jars   or 

small    vessels,    one   tea- 
spoonful    (1   drachm)    of 

the  fluid  may  be  taken 

for  every  cubic   foot   of 

space. 

As  carbon  bisulphide 

is  an  inflammable  and  un- 
pleasant liquid  to  handle, 

certain  precautions  must 

be  observed : — 

(1)   Keep  the  bisulphide  in  stoppered  (not  corked)  bottles  under  lock 

and  key,  and  in  a  place  where  it  will  uot  be  liable  to  be  thrown  down, 


Lid 


Fig.  2 

SoalQ  \ 


Gutter 

1 , " 

/2 

1 
-Side 

of 

Box 

Flange 
^^  Tin  Lining 


FT-MIGATINO. 


259 


Fig.  5 

Scale  '/2 


Viater 


(2)   Wlicu    fii  mi  gating',  do  so  in  a  plaoc  to  wliicli   no  ono    can   gvt 
access  while  fumigation 
is  proceeding. 

(8)  Allow  no  lights, 
no  pipes,  cigarettes,  or 
any  form  of  fire  near 
the  fumigation. 

(4)  Should  the  smell 
of  carbon  bisulphide  be 
noticed,  do  not  go  near 
with  a  light. 

(5)  There  is  danger 
from  the  vapour  only  if 

it  is  mixed  with  air  and  it  can  be  readily  smelt ;  should  the  bottle  leak, 
remove  it,  pour  the  fluid  into  another  bcttle  and  air  the  room  or  the  place 
where  the  smell  is  noticed. 

(6)  Do  not  stand  a  bottle  of  carbon  bisulphide  in  the  sunlight   or 
in  any  place  where  it  will  become  hot. 

(7)  Never  take  a  bottle  of  carbon  bisulphide  near  a  fire  or  lighted 
lamp. 


Fig.  313. 

Timler-hori'ng  Beetle, 
n,  larva  ;  h,  o,  imar/o ;  (\,  antenna ;  e,  timber.     [Maf/nijied.) 


For  fvmigating  i-mall  quantities  of  seeds,  the  box  figured  above  can 
be  used,  the  lid  of  which  fits  into  a  groove  filled  with  water  which  forms 

9  <v 


260 


INSECTS    INFESTING   GRAIN. 


an  air-tig-ht  cover.     Any  really  air-tight  box,  bin  or  vessel  can  be  nsod 

for  fumigating-. 
,         .  Provided  the   strength   and    period   men- 

/Mfk\  tioned     are     not    exceeded,    no     harm     will 

^^^K^   T  be  done  to  the  grain  either  for  food    or  for 

/^^^■V^  M^^y   beetles  are  found  boring   in    bam- 

/  ^^r  *l  p,  boo  and  dry  timber.  These  belong  chiefly 
^  to  a  single  family  of  small  cylindrical  brown 
beetles,  the  prothorax  hard  and  round,  the 
head  more  or  less  concealed,  the  general 
structure  fitted  for  life  in  the  cylindrical 
tunnels  made  in  the  wood.  The  life  history 
is  passed  in  the  bamboos  or  other  food. 
Bamboos  are  soaked  in  water  in  the  belief 
that    this   affords    protection   and   makes    the 


Fig.  314. 
Bamhoo-horing  Beetle. 
bamboo  unpalatable  to  the  insect. 
There  is  apparently  good  founda- 
tion for  the  belief  though  the 
precise  way  in  which  the  water 
acts  is  not  known.  Soaking  in 
salt  water  is  also  said  to  be  effica- 
cious. In  general  a  varnished 
bamboo  is  immune  from  attack 
so  long  as  the  varnish  is  not 
worn,  as  is  a  painted  one.  Soaking 
in  kerosene  or  painting  with 
kerosene,  followed  by  an  application 
of  linseed  oil,  is  good  not  only 
for  the  bamboos  but  for  furniture 
and  all  wooden  articles  that  are 
attacked.  This  is  effective  when  the 
wood  is  already  infested.  Where 
bamboos  are  to  be  used  in  the  roof 
of  a  house  or  in  any  similar 
position  not  in  a  room  or  exposed, 
painting  with  a  solution  of  arsenic 
is  a  sufficient  protection. 


Fig.  315. 

Areca  Nut  Weevil. 

a,  larva;  b,  pupa ;  c,  d,  imago.     {Magnified.) 


I 


ChAPTER  XX. 

INSECTS  ATTACKING  CATTLE. 

N  the  most  varied  situations  and  under  most  adverse  circumstances, 
we  find  insect  species  which  have  adapted  their  life-history,  their 
habits  and  their  structure  to  new  and  wholly  distinct  surroundings.  It 
is  therefore  not  surprising  that  we  find  distinct  branches  of  insect  life, 
wholly  adapted  to  obtaining  their  food  from  living-  warm-blooded  animals. 
Though  lacking  the  extraordinarily  well-ada,pted  life  histories  of  the 
parasitic  worms,  these  insects  are  not  behind  others  in  the  ingenuity  of 
the  means  whereby  they  overcome  adverse  conditions  :  their  habits  have 
no  parallel  in  other  insects ;  their  structure  is  profoundly  modified  to  fit 
them  to  their  surroundings,  and  they  form  an  extraordinarily  interesting- 
group.  These  insects  are  gathered  from  very  diverse  parts  of  the  animal 
kingdom  ;  the  bird  lice  are  Nturoptera  ;  the  quaint  West  African  rat 
parasite  is  one  of  the  Orthoptera  ;  the  beaver  parasites  are  Coleoptera  ;  most 
parasites  of  cattle  are  JJiptera.  The  fleas  are  an  abnormal  group  probably 
near  to  the  Biptera,  and  the  common  bug  is  one  of  the  Ilemiptera,  whilst 
finally  the  lice  are  abnormal  erratic  creatures  which  find  no  place  in  the 
larger  groups  of  insects.  It  is  not  possible  here  to  discuss  all  of  these ; 
the  fleas,  flies  and  other  creatures  that  affect  men^s  welfare  are  beyond 
the  scope  of  this  book,  and  we  are  concerned  solely  with  those  insects 
which  affect  cattle  and  domestic  animals,  the  fleas,  house-flies,  gad-flies, 
biting-flies,  bot-flies  and  flesh  maggots,  whilst  we  may  include  the  ticks 
which  are  not  insects,  though  closely  related. 

Fleas. 

Small  laterally  compressed  insects,  with  imperceptible  wings  and  great 
leaping  powers,  which  infest  warm-blooded  animals.  They  lay  eggs  in 
dirty  places,  in  corners,  on  the  hair  of  animals,  etc.,  from  which  hatch 
white  maggots,  worm-like  in  appearance  but  with  distinct  head,  which  feed 
on  blood,  animal  matter,  refuse,  etc.  These  pass  through  a  pupa  stage, 
emerging  as  the  imago  which  leads  a  parasitic  life  on  mammals  and  birds. 

The  whole  life-history  occupies  about  one  month  at  the  shortest. 
Fleas  breed  particularly  in  dirty  places  frequented  by  animals,  laying 
their  eggs  in  places  where  animals  lie  down.  Cleanliness  is  the  greatest 
check  on  them.  Fleas  should  never  be  allowed  to  breed  in  a  house  and  do 
so  only  because  there  are  domestic  animals  in  the  house  which  sleep  in 
the  house  and  are  not  properly  cared  for. 


^6^ 


IKSECTS    ATTACKING    CATTLII. 


Recently  the  part  played  by  the  rat  flea  iu  the  dissemination  of 
plague  has  been  discussed  by  Captain  W.  G.  Liston.  This  article^ 
should  be  read  in  full;  but  his  conclusions  briefly  are  that  the  rats,  infested 
with  fleas,  get  plague,  infect  the  fleas  and  die  ;  then  the  fleas,  with  the 
infection  of  plague  in  them,  have  no  food  and  attack  any  available 
animal ;  should  that  animal  be  man,  he  gets  plague  from  the  bite  of  the 
flea.  The  flea  in  this  case  is  simply  the  transmitter  of  the  plague,  and 
only  attacks  man  when  its  proper  food  (the  rats)  have  died  of  plague  or 
migrated.  If  experience  bears  out  this  theory,  the  importance  of  the 
flea  is  immensely  increased  and  the  commencement  of  plague  epidemics 
can  perhaps  be  checked. 


Ticks. 

The  commonest  external  parasites  of  cattle  are  ticks,  creatures  which 
when  full  grown  have  four  pairs  of  legs  and  are  allied  to  the  mites, 


Fig.  310. 
The  I'ersian  Tick.     (Maijnijjed.) 

spiders  and  other  aracJuiiih.  Tliey  may  be  seen  fastened  to  the  skin 
of  cattle  and  grow  to  a  large  size.  Specimens  have  been  sent  invfrom 
almost  every  domestic  animal  in  India,  and,  in  one  case,  the  Persian  Tick  ^ 
was  found  upon  human  beings. 

1  Journal  of  tlie  Bombay  Natural  History  Society,  XVI,  '1,  p.  253,  April  1905. 

2  Argas  jiersicus.     1' . 


TICKS. 


26^ 


The  life-lustoiy  of  ticks  in  g-eneral  is  a  simple  one.  The  full  o-rowii 
aud  full  fed  female  drops  froni  the  skin  on  to  the  g-round  and  lays  a 
large  number  of  eggs  in  a  mass ;  these  eggs  hatch  to  small  active 
creatures^,  with  three  pairs  of  legs^  which  run  about  on  vegetation 
and  are  believed  to  feed  upon  the  juices  of  plants.  They  fasten 
themselves  upon  the  skins  of  animals  as  they  pass  through  the 
vegetation  and  then  moult^  becoming  fully  developed  with  four  pairs 
of  legs.  There  is  a  large  number  of  species,  some  of  importance  in 
communicating  diseases  to  cattle  and  dogs.     The  treatment  of  the  above 


Fig.  317. 
Louse.  {Much  nun/iii/ied.) 


insect  and  ticks  is  a  matter  generally  of  expert  veterinary  knowledge, 
many  aj)plications  that  kill  the  insect  being  harmful  to  the  animals. 
General  cleanliness  in  the  stables,  cattle-sheds  and  fowl-houses  is  very 


264 


INSECTS  ATTACKING  CATTLE. 


important.  Washing-  animals  with  various  carbolic  preparations  is 
advisable  and  there  are  special  cattle  dips^  horse  and  dog  washes  prepared 
and  sold.  For  cattle  and  dogs,  the  insecticide  known  as  crude  oil  emul- 
sion is  a  safe  and  simple  application,  killing  all  forms  of  life  in  the  skin 
and  improving  the  condition  of  the  coat.  This  emulsion  mixes  in  water 
to  any  strength  and  can  be  worked  well  in  ;  it  can  be  left  to  dry  on  or 
be  washed  completely  out  of  the  skin  with  a  little  water.  For  some 
animals  it  is  far  better  than  carbolic  preparations,  wliich  should  not, 
for  instance,  be  applied  to  dogs  at  all. 


Lice. 

What  are  generally  termed  lice  are  insects  belonging  to  two 
distinct  orders,  the  biting  lice  [Nearoptera)  and  the  sucking  lice  (allied  to 
Heniiptera),  The  former  are  small  insects,  found  upon  the  hair  of 
domestic  animals  and  in  the  feathers  of  birds.  They  do  not  feed  upon 
blood  but  upon  hair,  flakes  of  skin,  etc.  Birds  rid  themselves  of  these 
pests  by  taking'  dust  baths,  rolling*  in  the  dry  dust  wliich  penetrates  the 
feathers    and   is   believed   to    check   the   lice.     Sucking   lice    are    small 

flattened  insects  without  wings 
found  upon  the  hair  of  pigs, 
goats,  cattle,  buffaloes  and  other 
animals.  They  extract  the  blood 
by  means  of  a  fine  suctorial  beak 
which  is  barbed,  and  their 
continued  presence  causes  sores. 
These  are  included  among  the 
horrible  creatures  which  infest 
the  skins  of  human  beings,  parti- 
cularly of  those  of  uncleanly 
habits.  No  reasonably  clean 
person  who  uses  soap  is  infected 
by  them.  A  peculiar  species  with 
long  proboscis  is  said  to  attack  the 
elephant,  but  it  is  not  known  if  this  occurs  in  India. 


Fig.  318. 
The   Baluchistan   Qad-Flt/.    {Ma(jnijied^ 


Qad=Flies. 

Large  active  flies,  quick  and  strong  on  the  wing,  which  bite 
cattle,  horses  and  human  beings,  often  drawing  blood.  These  flies  are 
familiar  to  any  one  who   travels  in    the  lower  slopes   of   the    hills,    in 


ttORSE   FLIES. 


265 


forests,  and  well-wooded  places.  They  are  powerful  insects,  with  a 
strong'  sharp  beak;  settling-  on  the  skin,  they  pierce  it  and  suck  out 
the  blood. 

Many  species  are  found  upon  cattle,  horses  and  other  animals,  and  these 

bite  man  freely. 
They  principally 
breed  in  forests. 
The  larva  of  one 
species  has  been 
found  in  India 
in  small  pools  in 
the  forests  and 
the  others  prob- 
FiG.  319.  ably  have  similar 

Larva  of  Gad-Fly,  Nongpok,  Assam.     {Magnified  twice.)  habits. 


Horse  Flies. 

A  family  of  peculiar  flies,  much  flattened,  which  settle    on    horses, 

cattle,  dogs,  etc.,  and 
live  on  their  blood. 
They  are  characteristic 
in  appearance,  and 
usually  marked  in  brown 
and  yellow.  They  can 
be  found  on  almost  any 
domestic  animal  and  on 
birds. 

Their  life-history  is 
peculiar,  in  that  the  larva 
does  not  leave  the  body 
of  the  parent  until  full 
grown  and  is  produced 
ready  to  pupate,  which 
it  does  at  once.  The  fly 
therefore  appears  to  lay 
a  pupa,  from  which  the 
new  fly  very  soon  comes. 
This  is  a  most  striking 
Fig.  320.  adaptation     to     parasitic 

The  Morse  Fly.    {Maguijied.)  life  as  there  is  no  larval 


^66  Insects  attacking  cattle. 

stage  to  provide  for.  The  flies  are  in  most  cases  very  active  and 
fly  from  animal  to  auimal,  but  tliey  often  stay  in  the  hair  or 
feathers  of  a  single  host  for  a  long  period. 


Bot  Flies. 

A  number  of  flies  do  not  feed  themselves  on  the  blood  of  cattle, 
but  their  larvae  live  in  their  tissues.  These  larvse  are  known  as 
bots  or  warbles  and  have  been  found  in  India  in  sheep,  cattle  and 
liorses.  The  sheep  bot-fly  deposits  eggs  or  living  maggots  in  the 
nostrils  of  the  sheep,  the  maggots  crawling  up  the  nostrils  and  fixing 
themselves  upon  the  mucous  membrane  of  the  nasal  cavities.  They  cause 
great  irritation,  much  mucus  is  produced,  on  which  they  feed  and  they 
injure  the  delicate  nasal  membranes.  The  maggot  remains  there  until 
nearly  one  inch  long,  when  it  loosens  its  hold  and  is  thrown  out  on  the 
ground;  it  pupates  in  the  ground  and  the  fly  presently  emerges.  The 
remedy  is  to  prevent  the  fly  from  laying  eggs  by  rubbing  the  nostrils 
with  tar,  train  oil  or  other  sticky  applications,  whose  smell  drives  off  the 
fly  and  renders  egg-laying  impossible. 

The  horse  bot-fly  lays  eggs  on  the  hair  of  the  mane,  the  shoulder, 
the  knee  or  some  other  part  within  the  reach  of  the  borsch's  mouth. 
These  eggs  are  fixed  to  the  hair  and  when  the  maggot  hatches,  it  is 
licked  off  by  the  horse  and  swallowed;  it  then  attaches  itself  to  the 
membrane  by  means  of  the  hooks  in  the  mouth  and  feeds  by  suction. 
When  full  fed  it  passes  through  the  alimentary  canal  to  the  ground  where 
it  transforms  to  the  pupa  and  emerges  as  a  fly. 

The  cattle  bot  or  warble-fly  is  found  as  a  larva  under  the  skin 
of  cattle,  buried  head  downwards  in  the  tissues  with  the  hind  end  of  the 
body  towards  the  oj)ening  in  the  skin ;  air  is  obtained  through  this 
opening  and  drawn  in  by  the  two  large  spiracles  on  the  last  segment. 
The  maggot  feeds  upon  the  putrid  matter  produced  in  the  sore ;  when 
full  grown  it  forces  itself  back  through  the  opening  in  the  skin  and  falls 
to  the  ground,  where  it  pupates.  This  insect  causes  a  large  amount  of 
damage  to  the  hides,  warbled  hides  being  of  very  inferior  value.  The 
condition  of  the  infested  animal  is  also  bad.  Treatment  for  this  and  for 
other  bot  maggots  is  a  veterinary  matter,  which  should  have  the  litten- 
tion  of  a  qualified  veterinary  man.  It  takes  the  form  of  sticky  smelly 
mixtufes  to  prevent  egg-laying,  the  removal  of  bots  from  the  skin  by 
pressure  or  the  desti'uctiou  of  bots  by  ajiplication  of  grease  or  ointment, 
^hc  species  discussed  above  al'c  the  most  common  in  India,  as  elsewhere. 


BlTlNG    I'LIES. 


'i6) 


Much  has  yet  to  be  learnt  of  them  and  of  the  bots  which  probably  attack 
wild  animals  in  India.  Cases  arc  on  record  of  bots  in  human  beingSj  but 
uo  precise  details  are  available. 

Biting  Flies. 

At  least  one  species  of  fly,  allied  to  the  notorious  tse-tse  fly  of 
Africa,  is  found  in  India  biting-  cattle,  horses  and  man.  This  insect  ^ 
is  not  universally  distributed  in  India  ;  it  breeds  in  manure,  decaying 
vegetation  and  filth  in  places  where  animals  are  kept.  The  life-history 
occupies  three  weeks,^  and  the  flies  are  found  sitting  on  trees  and  plants 
near  their  breeding  places. 

They  suck  blood  from  cattle,  horses  and  man,  biting  particularly 
in  the  early  morning :  the  bite  is  said  to  be  painful.  This  fly  is 
instrumental  in  the  spread  of  "  surra  ^^  in  horses  and  other  animals. 
It  is  kept  in  check  by  hymeuopterous  parasites  which  are  found  in  the 
larvse  and  pupae. 

Screw  Worms. 

Certain  flies  lay  their  eggs  or  larvse  in  wounds  on  animals,  the 
maggots  living  in  the  wound  and  setting  up  inflammation  and  blood 
poisoning.  The  Screw  Worm  of  the  United  States  and  the  West  Indies 
is  notorious  as  a  destructive  pest,  even  attacking  man  and  causing  death. 
Similar  maggots  have  been  found  in  wounded  cattle  in  India,  though 
it  is  not  known  to  what  species  they  belong.  These  flies  are  allied  to 
the  common  flesh  flies  and  house  flies,  their  normal  breeding  place 
being  decaying  animal  matter.  The  treatment  consists  in  smearing 
wounds,  sores,  etc.,  with  antiseptic  mixtures  such  as  carbolised  oil ;  a  clean 
aseptic  wound  is  not  infested.  If  larvse  are  already  in  the  wound, 
they  should  be  removed,  the  wound  washed  and  plugged  with  antiseptic 
dressing.  Such  maggots  are  by  no  means  uncommon  in  human  beings  in 
India  and  are  due  solely  to  uncleanness  and  the  neglect  of  wounds  and 
sores.     The  actual  species  concerned  has  not  been  ascertained. 

^  Stomoxi/s  calcitrans. 

2  As  worked  out  by  P.  G.  Patel  in  Nongpoh. 


CHAPTER  XXl. 


BENEFICIAL  INSECTS. 

IN  classing-  our  insect  life  aeeordiug  to  its  foodj  we  pointed  out  that 
whilst  a  very  great  number  of  insects  feed  directly  upon  vegetable  life, 
a  further  large  number  derive  their  food  from 
other  insects.  The  latter  we  may  term 
beneficial  insects,  since  they  are  the  greatest 
natural  check  upon  the  increase  of  the  des- 
tructive insects  which  attack  growing  crops. 
Beneficial  insects  play  a  very  important  part 
in  the  economy  of  nature.  Such  is  the  rate  of 
increase  of  the  majority  of  herbivorous  insects 
that  they  would,  if  able  to  breed  continuously, 
overrun  the  earth  and  devour  all  vegetable 
matter.  To  this  enormous  increase  is  opposed 
a  variety  of  conditions  and  forces,  which 
result  in  regulating  the  increase  of  all  classes 
of  life.  Climatic  changes  periodically  put  a 
check  to  the  increase  of  animal  life;  the 
absence  of  food  is  a  check,  which  is  however 
largely  inoperative  under  the  conditions  of 
modern  agriculture  ;  when  these  checks  fail, 
the  action  of  the  beneficial  insects  becomes 
apparent,  and  we. see  one  class  of  insects  living  at  the  expense  of  another 

and  proving  itself 
directly  beneficial  to 
man.  These  insects 
can  be  regarded  as 
forming  three  large 
divisions :  the  para- 
sites are  those  which 
live  as  larvae  with- 
in the  bodies  of 
their  hosts ;  the 
stinging     predators 

^^  ■     ^         .  ,        ,    ,  are  those  which  store 

Ihe  Moth-lorer   CateijJillar   oj  Cane. 

{Magnified.)  insects       tor       the 


Pig.  321. 

An  IchnemnoH  parasitic  on 

large  caterpillars. 

(^Natural  size.) 


The  parasite   of 


PAEASITKS. 


269 


nourishment  of  their  youno:,  and  the  predators  in  gfcneral  feed  themselves 
iTpon  living'  insects. 

Parasites  are  found  in  the  majority  of  species  of  insects  wliich  have 
been  reared  in  India  in  captivity.  The  '  ichneumons '  are  Eymenoptera, 
not  unlike  wasps  in  appearance,  which  lay  their  egg's  on  or  in  the  bodies  of 
caterpillars,  the  larva  which  hatches 
nourishing"  itself  at  the  expense  of 
its  host  (%.  321).  The  caterpillar 
continues  to  live  and  feed,  moulting" 
as  usual;  the  parasite  meanwhile 
g-rows  larger  and  finally  causes  the 
death  of  its  host.  In  many  cases 
the  larva  comes  out  of  the  body,  and 
turns  to  the  pupa  outside.  In  other 
cases  it  remains  within  the  dead 
body  until  it  emerges  as  a  winged 
insect.  Caterpillars  containing 
parasites  frequently  die  before  they 
can  become  chrysalides ;  in  some 
cases  they  become  chrysalides  and 


Fig,  323. 

Parasite  of  the  Egyptian  Syrphus. 

{Magnified  jive  times.) 


then  die.  A  caterpillar  may  contain  one  or  many  parasites;  as  many 
as  seventy  small  ichneumons  have  been  reared  from  the  body  of  a  Cotton 
Stem-borer.  Ichneumons  can  be  captured  in  the  field  or  more  readily 
obtained  by  rearing  various  caterpillars  and  grubs,  which  will  yield 
ichneumons  in   many  cases  instead  of   the  perfect  insect.     Ichneumons 


Fig.  324. 

I^ead  Caterpillar  showing  hole  of  etnergence  of  parasitic  fly  grub  and  the  pupa  of  the 
grub.     {Magnified  three  times.) 

not  only  destroy  caterpillars  but  the  grubs  of  beetles,  the  maggots  of 
flies,  and  the  grubs  of  bees  and  wasps.  In  some  cases,  one  ichneumon 
lays  its  eggs  within  the  body  of  the  grub  of  another  ichneumon  which  is 


270 


BENEFICIAL   INSECTS. 


already  living'  in  the  hodv  of  a  caterpillar ;  we  then  have  one  ichneumon 

parasitic  upon  another,  a 
singular  phenomenon,  which 
checks  the  too  g-reat  increase 
of  the  beneficial  insects 
(fi g.  oil o) .  Ichneumons  also 
lay  their  eggs  in  such  small 
insects  as  aphides,  and  even 
in  the  eggs  of  insects. 
One  species  lays  its  eggs  in 
the  eggs  of  the  moth-borer 
of  sugarcane  and  the  eggs 
of  many  insects  are  thus 
destroyed. 

Besides  the  ichneumons, 
there  axe  the  parasitic  flies, 
a  large  group  of  Dtftem 
which  behave  very  similarly 
to  the  ichneumons.  These 
flies  (fig.  325)  resemble 
house-flies  and  are  common 
in  the  fields.  They  lay 
their    eggs   on   caterpillars, 

and   other  insects,  the  maggot  that   hatches   destroying  the  caterpillar. 

As  in  other  flies,  the  full  grown 

maggot  forms  a  brown  seed-like 

pupa  (fig.  324)  usually  coming 

out  of  the  caterpillar  before   it 

does  so.     A  species  of  parasitic 

fly  lays  its  eggs  on  the  Bombay 

Locust  and  another  on  the  Red 

Cotton  Bug. 

As  a   rule   every   species  of 

parasite  is  found  only  on  one  or 

a    few    insects.      The    parasite 

of  the  Cotton  Stem-borer  is  not 

the  same  as  that  of  the  Moth- 
borer   of   sugarcane.     Parasites 

that  we  rear  from  distinct  insects  are  usually  distinct  themselves,  though 

the  same  parasite  may   be    found  in   two  species  of   insects  which  are 

very  much   alike.     Every  abundant   caterpillar   and   very    many   beetle 


Fig.  325. 

Fli/  vJiose  mar/qot  is  a,  parasite  on  leaf-eating 

cateiyillars.     (^Magnified.)     JPufa 

belotr,  itatwal  size. 


FiO.  326. 

The  parasite  of  tie  maggot  of  tlie  Sice^Siem 
Fly.     {Magnified.) 


PARASITES. 


271 


grubs,  fly  maggots,  oic,  liavc  tlicir  parasites ;  l)ut  parasites  themsolves 
are  dependent  upon  these  insects  for  food  and  become  exterminated  if 
their  liost  is  exterminated. 

It  is  advisable  not  to  destroy  parasitic  insects  and  when  possible 
their  increase  should  be  encourag-ed.  Tliis  is  unfortunately  rarely  possible, 
but  it  is  so  when  insects  are  collected  by  hand  in  larg-e  numbers  as  in 
handpicking"  Tur  Leaf  Caterpillars,  or  Cotton  Leaf-rollers.  In  such  cases, 
the  collected  larvge  and  pupse  should  be  placed  in  any  closed  receptacle,  as 
for  instance,  a  box  or  an  earthen  pot  covered  with  cloth.  Whatever 
parasites  there  are  hatch  out,  and  when  tlie  box  or  pot  is  carefully  opened 
in  the  lig*ht  they  fly  away.  As  a  rule  the  moths  or  butterflies  that  also 
hatch  fly  only  in  the  dark  or  are  too  large  to  escape  through  as  small  an 
opening  as  the  parasites  can.  Whenever  possible  it  is  advisable  to  put 
such  collected  insects  into  a  box  covered  by  a  piece  of  glass  ;  as  the  para- 
sites collect  on  the  glass,  the  moths  hide  away.  If  the  glass  is  gently 
lifted  the  parasites  escape  to  continue  their  useful  work. 

This  applies  also  to  eggs  of  insects,  which,   when  collected,  should 

not  be  burnt  but  placed  in  a  vessel  surrounded  by  water ;  the  insects  that 

hatch  from  the  eggs  cannot  escape,  but  the  parasites  can  fly  away. 
The    stinging    predators 

are  a  small  group  of  Hi/meno- 

ptera,   which  have  instincts 

of  so  high  an  order   as   to 

excite  the   admiration  of  all 

who  study  them.     We   may 

describe  the   life   of   one,^  a 

common  insect  in  the  plains. 

This  insect  may  be  found  in 

the  fields  flying  among  the 

plants  evidently  seeking  for 

something.    If  watched  with 

patience,  it  will  be  seen  to 

seek  for   caterpillars,    those 

green    caterpillars   so    com- 
mon on  gram,  tobacco,  and 

other  crops.     Having  found  a  large  green  caterpillar,  it  flies  to  it,  seizes 

it,  and  stings  it  on  the  lower  side  ;  the  caterpillar  struggles,  but  the   wasp 

holds  fast  and  repeatedly  stings  along  the  lower  surface  between  the  legs. 

The  caterpillar  then  becomes  motionless  and  is  helpless  ;  the  wasp  seizes  it, 

and  flies  off  to  a  little  distance  where  it  has  prepared  a  hole  in  the  ground  ; 

'  ^ffimpphila  Ifevigafa.     Sm. 


Fia.  327. 
Wasp  that  stings  caterpillars  and  lays  them  up 
mud  nests  for  its  young. 


272 


BENEFICIAL    INSECTS. 


Fig.  328. 
Digger  Wasp  that  stings   cater 


the  hole  is  a  narrow  tunnel  extending'  perhaps  one  inch  into  the  soil ;  into 
this  hole  the  oaterpillar  is  dragged,  and  laid  at  the  bottom  ;  the  wasp 
lays  one  eo-o*   upon   it  and  comes  out ;  it  then  fills  up  the  hole  with  small 

lumps  of  earth,  smooths  it  off  carefully 
and  goes  away  to  repeat  the  process. 
If  the  caterpillar  is  dug  up  and  kept  under 
suitable  conditions,  it  is  possible  to  see  what 
occurs.  The  egg  hatches  after  a  few  days 
and  the  small  white  grub  fastens  on  the 
caterpillar,  piercing  the  skin  and  pushing 
in  its  head.  It  feeds  upon  the  caterpillar, 
which  lies  still  and  motionless,  and  as  it 
grows  larger  it  stretches  into  the  body  of  the 
caterpillar,  slowly  devouring  it.  In  time  the 
caterpillar  is  eaten  out,  only  the  skin  remain- 
pillors.  ing,  and  the  grub  has   grown  into  a  large 

white  insect.  It  then  spins  a  cocoon  of  tough  silk,  within  which 
it  turns  to  the  pupa  and  eventually  emerges  as  a  wasp.  It  mates 
and,  if  a  female,  does  as  its  parent  did,  preying  upon  green  caterpillars 
(fig.  328). 

The  habits  of   this  insect  are  similar  to   those   of  all   the   stinging 
predators.     The  siugu-  s,      j^      / 

lar   fact    is     that    the  ^     ^^     '' 

caterpillar  is  stung  in 
such  a  way  as  not  to 
kill  it  but  to  paralyse 
it.  If  the  caterpillar 
were  dead,  it  would 
decay  and  the  grub 
hatching  would  find 
no  food ;  if  the  cater- 
pillar were  alive  and 
could  walk,  it  would 
walk  away  with  the 
egg,  which  would  be  killed  by  exposure  to  sun  and  air.  By  paralysing 
the  caterpillar  the  mother  ensures  a  supply  of  living  food  for  her 
young.  Stinging  predators  are  common  in  the  fields ;  some  make 
nests,  others  bury  their  prey  in  the  ground,  some  are  to  be  found 
in  our  houses  (fig.  327).  They  prey  upon  all  manner  of  small  insects, 
upon  spiders,  and  upon  some  of  the  larger  insects.  Their  habits  are 
extremely  diverse  and  display  an  ingenuity  that  has  excited  the  admiration 


Fig.  329. 

Lady-hird  Beetle  and  its  grub.  (^Magnified  and 

natural  size.) 


PREDATOKS. 


273 


■^'-r^&. 

^.^ 

6. 

t 

Fig.  330. 
Six-spotted  Lady-bird  Beetle. 


of  all  naturalists.     They  are  distinctly  beneficial  and  aid  in  the  cheeking- 
of  insects  throughout  the  year. 

Lastly,  we  have  the  "predators,"  a  vast  number  of  insects 
which  live  by  capturing  and  devouring 
other  insects.  These  are  really  of  two 
kinds,  those  which  we  find  specially  attack- 
ing particular  classes  of  insects,  and  those 
which  catch  and  devour  all  that  they  are 
able  to. 

Of  the  first,  there  are  many  which  are 
found  attacking  plant-lice,  mealy  bugs  and 
scale  insects  and  those  should  be  familiar  to 
every  one. 

The  Lady-bird  Beetles  are  small  rounded 
beetles,  about  the  shape  of  a  split  pea, 
coloured  in  red,  yellow  and  black  as  a  rule. 
The  life-history  in   all  is  the  same,  and  we 

may  describe  that  of   the  commonest  beetle   in   India,   the   Six-spotted 

Lady-bird  Beetle.^ 

The   female   beetle   deposits   her   eggs  on   plants    where    there    are 

colonies   of   green-fly    [aphis]  or  other  food  for  the  young.      The  eggs 

are   yellow,    almost    cigar-shaped,   about  one-twentieth  of  an  inch  long, 

laid  in   little    clusters    of    10    to    20    eggs.     In   four   or    five   days    the 

eggs    hatch,    a   tiny   dark-coloured    grub    coming   out.     The    grub    has 

three    pairs    of   legs,    a  body  set  with  spines  and  tapering  to  the  hind 

end,    and   is  nearly   black.     It   runs   about, 

feeding  upon    other  aphides  and   it   is   very 

voracious;    it  rapidly  grows  larger.     Yellow 

and   white   spots   appear  on   it   after    some 

days    and    it    is    then    more    easily   recog- 
nised.     The    grub    does    not    grow    to     a 

length   of   more   than    about    one-quarter  of 

an    inch,   living    for    about    ten    days.     It 

then   fixes   itself   head  down    by    the    tail, 

and   the    skin   is   shed,   exposing   the  pupa. 

•  The     pupa    is    round,    hanging    from    the 

plant,     of     a    dark-red     or     orange    colour 

\v\\h  black  spots.     Great  numbers  of  these 

may    be   found  on  the   plants  when  aphides 

are  abundant,  and  they  are  very  easily  seen  on  the  leaves. 


Fig.  331. 
Seven-spotted  Ladi/-hird  Beetle. 


64.  Chilomenes  sexmaculata  F.     (Coccinellidse.) 


274'  BENEFICIAL    INSECTS. 

After  about  six  days  the  beetle  comes  out,  and  it  too  feeds  upon  aphis. 


Fig.  332. 
^ggn  of  Green  Chri/sopa. 


{^Magnified.) 


The  beetle  is  shaped  like  a  half  pea,  the  wings  covering  most  of  the 

body.  There  are  six  little  black 
spots  on  the  upper  surface,  the 
general  colour  being  yellow  or 
orange.  The  beetle  has  good 
biting  mouth-parts  and  feeds 
actively  upon  aphis.  The  females 
lay  about  90  eggs  each,  in  little 
clusters,  and  then  die. 

The  life  of  this  beetle  may  be 
long  or  short,  depending  upon 
whether  it  can  find  food  for  itself 
and  its  young,  when  it  will  lay 
eggs.  Large  nvimbers  of  beetles 
are  found  during  the  cold  weather 
and  dry  weather  before  the  rains, 
seeking  for  aphides  on  which  to 
feed.  These  beetles  probably  live 
a  long  time.  When  food  is  plenti- 
ful, the  whole  life  from  egg  to 
perfect   insects    does    not   exceed 

four  weeks,  and  one  brood  succeeds 
Fig.  333.  ' 

Broum  Chrysopa  larva.     {Magnified.)  another  rapidly. 


I/ADYBIRD   BEETLES. 


275 


As  each  beetle  lays    nearly  one    hundred   egg's,  and  each  g-rub  that 

comes  out  eats  from  one  to  two  hundred 
aphis  per  day,  the  destruction  of  aphis 
may  be  very  rapid.  Tliis  beetle  is 
very  abundant  over  a  larg-e  part  of  the 
plains  in  India  feeding"  princdpally  iipon 
cotton  aphis.  With  it  is  another, '  the 
Seven-spotted  Beetle,  which  feeds  upon 
wheat  aphis  in  particular  and  becomes 
enormously  abundant  in  aphis-infested 
wheat. 

Other   species    include   the   very   small 
brown       beetles,^       whose         larvae       are 


Fig.  334. 

Cocoon  of  Green  Chrysofa. 

{Magiiified.) 


clothed  in  dense  white 
processes  which  give 
them  the  appearance  of 
a  mealy  bug.  These 
larvae  are  found  feed- 
ing upon  cotton  aphis 
on  tur  aphis,  on  the 
cotton  mealy  bug  and 
on  many  other  com- 
mon insects.  There  is 
a  large  number  of 
other  species  common 
in  the  plains,  but  the 
above  are  the  most 
important. 


Fig.  336. 
Green  Chrt/sopa. 


Fig,  335. 
Brown  Chrysopa  Fupa.     CMagmfied.) 

The  lace-wing  flies  are  very 
delicate  green  or  brown  insects, 
with  large  wings  and  golden  eyes, 
which  are  found  commonly  upon 
plants  attacked  with  aphis.  They 
lay  eggs  which  have  the  appearance 
of  a  rice  grain  set  upon  a  small 
stalk.  A  number  of  these  are  laid 
together  in  a  cluster  on  the  leaf  of 
the  infested  plant. 


'  Coccinella  septempnnctata  L. 
^  Scymnns  spp. 


276  BENEFICIAL  INSECTS. 

The   larva    that     hatches    is    an    active    spiny    insect,    with    long- 


Fig.  337. 
Larva  of  Chrysopa,  just  hatched,  on  the  egg,     {^Magnified.) 

sharp  jaws ;  it  runs  about  the  plant  seeking  for  aphis  and  when 
it  finds  one,  the  jaws  are  inserted  and  the 
juice  sucked  out  till  only  the  shell  is  left. 
In  some  species  the  larva  covers  itself  in  the 
cast  skins  of  its  victims  and  goes  about  with 
a  thick  mass  of  them  on  its  back.  This 
larva  destroys  a  large  number  of  the  aphis 
before  it  pupates  ;  the  pupa  is  found  in  a 
small  white  cocoon  or  in  a  fold  of  the  leaf 
under  a  thin  covering.  These  insects  are  very 
numerous  in  the  plains,  thoug-h  they  commonly 
escape  notice.  A  bad  attack  of  aphis  brings 
them  in  numbers  and  the   flies   are   attracted   to 


Fig,  338. 

jEgg  of  Sgrphus 

Fig   laid    on   leaf. 

(Natural  size 

and  much  magnifed.) 


light. 


^flTfr 


Fig.  389. 
Qrub  of  Syrphus  Fly.     {Magnified  five  times.) 


SYEPHUS   FLIES. 


til 


Tlie  Syrpluis  flics  are  another  important  check  on  tlie  plant-lice  and 
may  be  found  in  any  field  where  a  crop  is  infested.     The  fly  is  a  o-raceful 


A --A  ^-Ai —■></>      -jSt    _-><*-. .y« 


Fig.  340. 
Grub  of  Syrphus  Fly.     {Ilagnifled  five  Hmes.) 


A-  - 

■;>' 

•i^ 

Fig.  341. 

Empty  puj)"-  case  of  Syrphvs.     {Mar/vified  five  times.) 


Fig.  342. 
Syrphns  Fly.     {Magnified  five  times.) 


two-winged  fly,  coloured  in  black  and  yellow,   which   "hovers''   in   a 
very  noticeable  manner,  remaining'  motionless  on  the  wing  suspended  in 


278 


Beneficial  insects. 


the  air;    larg'c  numbers   can  be  seen   in  a  wheat-field  where    aphis    is 

abundant.  These  flies  deposit  small 
wliite  egg's  singly  on  the  wheat  near  the 
colonies  o£  aphis;  a  maggot  hatches, 
formed  like  the  typical  fly  maggots, 
thick  at  the  hind  end,  tapering  to  a 
point  at  the  headless  front  end,  with  a 
pair  of  strong  hooks  in  the  mouth; 
the  maggot  is  green  and  moves  slowly 
about  the  leaf,  feeling  in  every  direc- 
tion. It  is  blind  and  strikes  about 
it  in  a  curious  tentative  fashion,  feeling 
for  a  victim.  The  plant-lice  caught 
by  it  are  drawn  in  with  the  hooks, 
sucked  out  dry  and  thrown  aside. 
These  maggots  demolish  whole  colonies 
of  the  plant-lice  and  finally  turn  to 
one    species^    is    very    common    in 


Fig. 343. 

Ground  Beefle  that  attacks  the  young 

North-  West  Locust. 


the  pupa  on   the  leaf.      At   least 
the  plains,  feeding  on  aphis  of  all 
kinds. 

Many  insects  are  found  feeding 
Upoti  special  destructive  insects. 
The  Six-spotted  Tiger  Beetle^  is 
abundant  in  rice-fields  in  Bengal ; 
it  flies  with  great  rapidity  and  feeds 
upon  the  Rice  Bug.  A  ground 
beetle  ^  is  said  to  feed  upon  the 
young  North- West  locusts.  The 
larvae  of  other  ground  beetles  feed 
Upon  such  caterpillars  as  live 
exposed  oil  the  plant ;  these  are 
small  slender  black  insects,  which 
congregate  on  plants  infested 
with  small  caterpillars  and  destroy 
them. 

There  are  in  addition  many 
insects  which  prey  promiscuously, 
their  life  history  not  being  speci- 
ally modified  in  relation  to  their  prey  as  in  predators  discussed  above. 

^Syrphus  cpgyptius.   Wied.  (Syrphidie.)  )  ^  Ciciiidela  sexpunctata  L.  (Cicindelidse.) 
^  C'alosoma  orientale  Ho.  (Carabidte  ) 


Fio.  344. 
The  Six'SjJotled  Ground  Beetle. 


PREDACt:OUS  INSECTS. 


279 


Thedrat;-ou  flics  (%.  J,  pag-c  203)  wliich  liawk  in  the  sunlight  are  catching 
small  flying  insects  and  must  account  for  a  vast  number  of  the  smaller  forms 

of  insect  life  daily.  The  praying  mantises 
are  common  in  jungle  and  bushy  vegetation, 
where  they  wait  for  butterflies  and  other 
large  insects.  The  ant-lion  in  its  pit  destroys 
the  smaller  creatures  that  walk  on  the  soil. 
Wasps  when  hungry  catch  caterpillars 
and  eat  them;  the  Mantispa  and  the 
Panorpids  lurk  in  the  deep  woods  and 
jungles,  hunting  down  the  weaker  flying 
insects  for  their  food.  Everywhere  on 
the  soil  are  the  ground  beetles,  the  flat 
dark  beetles  which  live  wholly  by  their 
prey  and  which  gather  so  abundantly 
where  insects  abound.  Even  underground 
the  mole  cricket  and  the  hherwa  drive  their 
tunnels,  seeking  out  the  grubs  and  other 
insects  hiding  there.  In  the  bark  of  trees 
are  many  beetles,  wholly  carnivorous  and 
devouring  the  many  forms  of  insect  life 
that  dwell  there.  Even  the  plant-feeding 
caterpillar  is  in  some  cases  predaceous,  the 
caterpillar  of  one  butterfly  ^  and  several 
moths  2  feeding  upon  mealy  bugs.  Among  the  flies  the  big  hairy 
robber-flies  are  predaceous  and  catch  grasshoppers,  bees,  wasps,  and 
other  strong  insects.  Many  other  Bipiera  are  predators,  as  are  a  large 
part  of  theljugs,  distinguishable  by  their  curved  beaks.  The  total  list 
would  be  a  very  long  one  and  embrace  parts  of  the  large  orders  and  of 
very  many  families. 

I'redaceous  insects  are  common  everywhere  and  in  every  possible 
situation  where  other  insects  get  food.  They  cannot  always  be  identified 
as  predators  until  their  habits  are  accurately  studied,  and  one  cannot  at 
sight  recognise  a  predaceous  from  a  herbivorous  insect  in  every  case. 

To  the  observer  of  nature,  these  insects  are  of  interest,  and  the 
deeper  one  looks  the  more  one  feels  the  wonder  of  that  balance  of  life 
which  is  apparently  so  evenly  maintained.  It  is  very  rarely  that  an 
insect  becomes  abundant  and  for  the  time  outwits  its  foes  j  the  more  it 
does  so,  the  more  do  its  foes  prosper  till  they  reduce  it  to  its  level ;  nor  do 

^Spalgis  epius  F.    (LjcEenid^.)  1   ^  EubUmma  i».,  (Noctuidee),  &  Various  Tineidae. 


h' 

X     \ 

\ 

1^ 

it 

X 

1: 

i^*'^''' 

1 

\ 

K 

^i' 

Fig.  345. 
A  Fraying  Mantis. 


^80 


fiENEPICIAL     INSECTS, 


the  foes  escape  but  they  in  turu  are  checked  till  all  species  can  live  and 
fill  their  place  in  the  natural  world,  the  balance  of  life  evenly  kept  between 
the  herbivores,  the  scavengers,  the  parasites  and  predators.  In  this 
connection  we  may  mention  the  birds,  which  do  so  much  to  keep  the 


Fig.  346. 
A  Fraying  Mantis. 

balance  even  by  snapping-  up  all  insects  that  become  abundant ;  an  insect 
that  escapes  its  foes  and  outruns  its  parasites  is  apt  to  fall  a  victim  to 
birds  as  do  the  termites  when  they  emerge  in  swarms ;  if  not  to  a  bird, 
then  to  a  lizard,  a  toad  or  a  bat.  All  these  are  useful  and  all  should  be 
encouraged.  A  large  number  of  birds  are  wholly  insectivorous,  a  large 
number  are  partly  so,  and  every  one  of  these  deserves  protection  and 
encouragement.  They  fill  an  extraordinary  place  in  nature  as  they 
move  from  place  to  place,  they  are  nearly  omnivorous  insect-eaters 
and  they  snatch  up  the  floating  balance  of  insect  life,  acting  as  a 
kind  of  safety-valve.  For  the  birds  we  should  plant  trees,  which  rarely 
harbour  crop  pests,  and  especially  such  trees  as  figs  on  which  the  mynas 
ffather  and  feed. 


APPENDICES. 


APPENDIX  A. 

USEFUL  INFORMATION. 


T 


COST  OF  INSECTICIDES. 

HE  coi^t  of  insecticides  depends  on  the  lo^al  i»-ices  of  the  various  ingredients,  but 
the  following  may  be  taken  as  average  prices  per  100  gallons  (12  maunds) :  — 

Ks.  A.    r. 

Lead  arscuiate    .... 
Kerosene  emulsion,  soft  soap 

„  „  hard  „ 

Rosin  wash         .... 

„      compound 
McDougal's  Insecticide 
Crude  oil  emulsion        .  . 

The  quantity  of  insecticide  used  per  acr 

Cotton  or  Tur      .... 

Youug  Sorglmm 

Sweet  Potato,  Groundnut,  etc. 

Coffee 

Tea 

Mustard     .  .  .  •  • 

Wheat       .         .■        . 


inous  crops  is  as 


follows  : — 

80  to  100  gallons. 

60 

60 

80—160 

75—150 

60—100 

50—80 


FORMUL/E. 
I.— Lead  Arseniate. 

Paste— One  pound  in  66  gallons  of  water  with  the  addition  of  3  pounds  of  lime 
and  6  pounds  of  jaggery  or  gur  if  available.  Stir  well  before  applying.  One  ounce 
of  paste  is  the  charge  for  a  kerosene  tin  full  of  water  or  for  the  Knapsack  Spraying 
machine. 

Potvdet:—Om  pound  in  100  gallons  of  water  with  5  pounds  of  lime  and  10  pounds 
of  jaggery  or  gur.  Stir  well.  The  charge  for  a  kerosene  tin  of  water  is  two-thirds  of 
an  ounce,  about  a  teaspoonful. 

One  pound  miied  well  with  20  to  50  pounds  of  any  fine  neutral  powder,  such  as 
lime,  ashes,  road  dust,  etc. 

2. — Kerosene  Emulsion. 

Boil  half  a  pound  of  sliced  har  soap  in  1  gallon  of  Water  till  dissolved.  ^  Take 
off  the  fire  and  add  2  gallons  of  kerosene,  agitating  or  beating  the  mixture  till  the 
kerosene  is  completely  emulsified.  This  is  stock  solution  to  be  diluted  with  6  to  10 
parts  of  water  before  use.     With  hard  water  more  soap  is  required. 

3.^--Crude  Oil  Emulsion. 

One  gallon  of  emulsion  mixed  with  66  gallons  of  cold  water.  The  charge  for  a 
kerosene  tin  full  of  water  is  half  a  pint. 


284  APPENDIX    A.       USEFUL   INFORMATION. 

4.— McDougal's  Insecticide. 

One  gallon  of  emulsion  mixed  with  a  few  gallons  of  water  and  then  made  up  to  60 
to  100  gallons. 

5.— Rosin  Compound. 

Powder  2  pounds  of  rosin  and  1  pound  of  washing  soda  (sodium  carhonate) 
crystals.  Place  these  in  a  kerosene  tin  or  large  metal  vessel,  with  enough  water  to  cover 
them,  and  hoil. 

Continue  boiling  till  both  are  dissolved  and  then  slowly  add  cold  water  to  the 
steadily  boiling  fluid.  Water  is  to  be  added,  a  very  little  at  a  time,  for  fear  of  chilling 
the  liquid,  and  the  mass  should  gradually  be  brought  up  to  2  gallons.  The  liquid 
changes  as  the  boiling  proceeds,  becoming  thick  and  soapy  ;  after  boiling  for  half  an 
hour  or  longer,  the  liquid  becomes  clear,  thin,  of  a  deep  brown  colour.  Continue  boil- 
ing, pouring  a  few  drops  of  the  mixture  into  cold  water  at  intervals  ;  at  first  the  wash 
on  mixing  with  cold  water  forms  a  slightly  milky  opaque  fluid,  but  after  some  minutes' 
further  boiling,  it  fonns  a  clear  amber  liquid  on  being  mixed  with  cold  water. 

This  is  tlie  test  of  the  liquid  being  finished  and  it  should  on  cooling  remain  clear. 
To  this  stock  solution  6  gallons  of  water  may  be  added  to  make  the  strong  wash,  10 
gallons  to  make  the  normal  wash.  One  pound  of  rosin  is  used  for  every  4  to  6 
gallons  of  wash  required,  and  half  as  much  soda.  The  wash  liceps  indefinitely  if 
properly  prepared,  and  it  is  best  to  keep  the  stock  solution  and  dilute  it  as  required. 


6.— Rosin  Wash. 

Powder  3  pounds  of  rosin  and  add  it  to  half  a  ponnd  of  caustic  soda  (98  per 
cent.)  dissolved  in  half  a  gallon  of  water  in  a  kerosene  tin.  Boil  and  when  the  rosin  is 
dissolved  add  half  a  pint  of  fish  oil.  Continue  boiling,  slowly  adding  cold  water,  till 
the  mixture  amounts  to  3  gallons.  If  the  mixture  is  then  a  clear  thin  brown 
liquid,  which  mixes  with  water  producing  no  milkiness,  it  is  finished  and  may  be 
removed  from  the  five.  Dilute  with  12  gallons  of  water  to  make  wash  ready  for 
use.  One  pound  of  rosin  is  used  for  every  5  gallons  of  wash  required.  If  caustic 
soda  of  98  per  cent,  purity  cannot  be  used,  use  a  proportionate  quantity  of  70  per  cent. 
(f  lb.)  or  lower  grade  caustic. 

7. — ^Tobacco. 

Soak  2  lbs.  of  tobacco  in  2  gallons  of  water  for  24  hours  or  boil  for  half  an  hour. 
Dissolve  ^  lb.  bar  soap  or  1  pint  of  soft  soap  in  the  mixture.  This  is  the  stock 
solution.     Dilute  with  seven  parts  of  cold  water. 

8. — Sulphur. 

Mix  20  lbs.  of  ground  sulphur  or  flowers  of  sulphur  with  80  pounds  of  siftfed  or 
slaked  lime  or  wood  ashes. 

An  alternative  is  to  boil  5  pounds  of  sulphur  and  5  pounds  of  lime  in  water  and 
make  np  to  40  gallons  with  water. 

Another  formula  is  to  mix  8  pounds  of  sulphur  with  10  pounds  of  soft  soap  in 
boiling  water  and  make  this  up  to  40  gallons  with  cold  water. 


FORMULA.  ^85 

9'— Kerosene  Milk  Emulsion. 

Mix  aacl  churu  or  shake  well : — 

1  gallon  Sour  milk  ,  .  ,  ^  ,  -, 

2  gallons  Kerosene j  Stock  solution. 

Dilute  with  8  to  15  parts  of  water. 

10. — Borer  Wash. 

1  pint  Crude  carbolic  or  phenyle       .         .         .-x  Dissolve  soap  in  hot  water,  stir  in 

2  lbs.  Soft  soap  (or  hard  soap,  i  lb.)  .  C      carbolic.   Add  ten  gallons  of  water 
1  gaUon  Water,  hot         ....         J      and  enough  clay  to  thicken  it. 

II. — Carbon  Bisulphide. 

1  oz.  per  100  lbs.  of  grain. 

1  to  li  lbs.  per  ton  of  grain. 

1  drachm  (teaspoouful)  per  cubic  foot  of  space. 

1  oz.  per  15  cubic  feet  of  space. 

12. — Cockroach  Paste. 

1  oz.  Boracic  acid  .  .  ,  ,  ,  ,  -j 

2  oz.  Jaggery,  or  syrup  .         .  ,         ,  j  ^^^  Mvell. 

13.— Gondal  Fluid. 

4  oz.  Dekamali  gum  (Gum  of  Gardenia  gmnmif era). 
8  oz.  Hing  (Asafoetida). 
8  oz.  Gugul  (Bazar  aloes). 

3  oz.  Haudiba  bagda  (Castor  cake). 

Mix  well  with  water,  add  clay  to  thicken  and  paint  on.     It  ferments  and  must  be 
kept  open.     Total  cost  14  aunas. 

14. — Soluble  Arsenic. 

1  part  White  arsenic       ,  .  ,  .  . ) 

4  parts  Washing  soda {  Boil  m  water  till  dissolved. 

For  watering  foundations,  earthwork,  etc.,  dilute  with  30  parts  of  water.     (Is  an 
excellent  weed-killer.) 

i5> — Lead  Arseniate. 

4  oz.  Arseniate  of  soda "^  Dissolve  separately   in   water    and 

10  oz.  Acetate  of  lead        .         .  .         .  , )      mix. 

16.— Arseniate  of  Lime. 

1  Id   A-fSPmo 

4  lbs.  Washing  soda       .'         .'         .'         .'         ^ )  Boil  till  dissolved.     Make  up  to  4 

2  gallons  Water 3      gallons  with  water. 

Add  one  pint  to  four  gallons  (kerosene  tin  full)  of  water  and  add  4  oz.  lime, 
This  is  a  substitute  for  lead  arseniate, 


286 


APPENDIX    A.       USEFUL     INFORMATION. 


17. — Arseniate  of  Copper. 


2J  lbs.  Copper  sulphate  . 
4  gallons  Water      .         , 


J  Dissolve. 


Stock  solution  A. 


' )  Boil 
')      gs 


1  lb.  White  arsenic  . 
5  lbs.  Washing  soda 

2  gallons  Water 

Mix  equal  parts  of  A  and  B,  and  dilute  with  35  parts  of  water 
This  is  equivalent  to  lead  arseniate  standard  solution. 


till    dissolved  :  make  up  to  4 
gallons.     Stock  solution  B. 


18. — Kerosene  and  Lime. 


20  parts  Lime 
1  part  Kerosene 


(by  volume)  ■)  pi^e   j-oad  dust  or  any  fine  neutral 
(by  volume)  >      powder  Mill  do. 


The  same  mixture  can  be  made  with  sanitary  fluid,  cheap  phenyle,  or  other  carbolic 
fluids. 


STRENGTHS  OF  INSECTICIDES, 

The   following   table   gives  the   weights   or  volumes   of   insecticides  to  be    used, 
calcukted  for  the  kerosene  tin  or  spraying  machine  holding  four  gallons:— 


Weak. 

Standard. 

Strong. 

Lead  arseniate,  powder   . 

Ditto,          paste      .          ,         . 
Rosin  wash,  stock  solution 
Rosin  compound,  stock  solution 
Kerosene  emulsion,  stock  solution      , 
Crude  oil  emulsion 

McDougal's  insecticide  and  fungicide 
Tobacco  decoction 
Kerosene  milk,  S.  solution 

i  oz. 
f  oz. 

2  pints 

3  quarts 
2  pints 

i   pint 
*      » 

X 

2       » 
2  pints 

i  oz. 
5  oz. 
3  pints 
1  gal. 
3  pints 

i    » 
1    „ 

3  pints 

1  oz. 
1|  oz. 
5  pints, 
li  gal. 
5  pints. 
1  pint. 

1  „ 

2  piftts. 
5      „ 

Arsenic.  —  The  fatal  dose  for  an   adult  is  from  one  to  two  grains,  equivalent  to 
three  to  five  grains  of  lead  areeniate,  obtainable  by  dyinking  from  balf  to  a  third  of  a 


WEIGHTS    AND   MEASURES. 


287 


pint  of  standard  waf5li.  The  antidote  is  an  omotic  followed  by  oil  and  lime  water,  soap 
suds  or  milk  ;  an  emetic  is  made  by  mixing  mustard  flourlone  table.^poonful,  common 
salt  one  teaspoonf  nl,  and  water  ten  to  twelve  ounces. 


WEIGHTS  AND  MEASURES. 


16  dram 

make    1  ounce  (oz.)                     = 

2| 

tolas. 

16  ounces 

„       1  pound  (lb.)                     = 

8 

chittacks. 

28  pounds 

„       1  quarter  (qr.)                   = 

14 

seers. 

4  quarters  (112  lbs 

.)  „       1  huudredweight  (cwt.)    = 

1 

maund  14  seers. 

20  liuudredweight 

„       1  tou                                   = 

271 

maunds. 

4  gills 

„       1  pint  (pt.)                        = 

10 

chittacks. 

2  pints 

„       1  quart  (qt.)                        = 

1 

seer  4  chittacks. 

4  quarts        . 

„       1  gallon  (gal.)                   = 

5 

seers. 

1  fluid  ounce  weig 

IS  1  oz. 

1  pint  (20  fl.  ounces)  of  water  weighs  li  lbs. 

1     „     (      ..        „ 

)  of  kerosene  weighs  13  J  oz. 

1  lb.  of  kerosene  measures  li  pint. 

1  pint  of  slaked  lime  weighs  13 — 14  oz. 

1  pint  of  lead  arseuiate  powder  weighs  28  oz. 

1  gramme 

=     15-432  gi-aius. 

1  kilogramme 

=■     35  oz.  120  grains. 

1  ounce 

=     28"35  gramme. 

1  pound 

=  453-58 

1  litre 

=     35^  fl.  OS. 

TREATING  COTTON  SEED. 

For  five  seers  of  seed,  mix  two  handfuls  of  clay,  one  of  cowdung  and  enough 
water  to  make  a  paste.  Rub  the  seeds  in  this  mixture,  letting  them  fall  through  the 
fingers  as  they  get  covered.  Dry  in  the  shade.  To  test  them,  throw  the  seeds  into 
water,  when  all  that  float  may  be  removed  as  bad. 


SURFACE  CATERPILLAR  BAIT. 

For  five  acres,  mix  one  maund  (40  seers)  of  bhusa  with  six  gallons  (30  seer.s)  of 
water  in  which  one  seer  of  white  arsenic  (Sambiil)  and  two  seers  of  gur  or  jaggery 
have  been  dissolved.  This  makes  a  paste  which  is  put  down  over  the  field  in  small 
heap?  about  two  yards  apart. 


288 


APPENDIX   A.       USEFUL    INFORMATION. 


To  make  a  bag  and  frame  with  opening  of  four  feet  by  two  feet. 

Sufficient  strips  of  clotli  are  taken,  each  fourteen  feet  long,  sewn  together  by  their 
long  edges  to  make  a  piece  fourteen  feet  by  six  feet.  The  two  ends  are  then  brought 
together  and  the  sides  sewn  up.  This  makes  a  flat  bag,  to  which  strong  cloth  tags  are 
sewn,  the  first  at  one  seam,  the  next  two  feet  from  that,  the  third  four  feet  from  the 
second,  the  fourth  two  feet  from  the  third  and  four  feet  from  the  first.  Bamboos  of 
two  feet  length  are  fixed  between  the  two  pairs  of  tags  two  feet  apart  and  the  bag  is 
ready  {see  Pig.  A).  ,  . 


Fig.  a. 
Bag  with  bamboos  ready  for  use. 

The  frame  is  made  of  four  pieces  of  bamboo  (a),  each  four  feet  three  inches  long, 
laid  in  a  square,  the  ends  of  two  bamboos  on  the  ends  of  the  other  two.  Two  cross- 
pieces  (J)  of  split  bamboos,  each  five  feet  eight  inches  long,  are  laid  diagonally  across 

d 


Fig.  B. 

Bamboo  frame. 


the  square.  Two  pieces  of  bamboo,  each  two  feet  three  inches  long  (c),  are  placed 
upright  at  the  corners  of  one  side,  and  two  split  bamboos  (d),  each  four  feet  eight  inches 
long,  are  placed  from  the  top  of  these  uprights  to  the  nearest  corner.  A  cross  bar  (e)  four 
feet  three  inches  long  is  then  placed  to  unite  the  top  of  the  two  uprights  {see  Pig.  B). 


BAGS   AND   NETS. 


289 


5'    2 


As  the  bamboos  are  placed  in  position  they  are  bound  with  string  or  fibre  in  the 
order  given  above.  Enough  bamboo  should  project  at 
the  ends  to  allow  of  tlieir  being  bound  together.  This 
makes  a  frame  to  the  front  of  which  the  bag  above  is 
attached  by  the  tags. 

In  these  figui'es  three  inches  extra  length  is  allowed 
to  permit  of  the  bamboo  being  bound  ;  tlie  resultant 
frame  is  then  of  the  size  to  accommodate  the  bag.  The 
two  feet  long  bamboos  used  for  keeping  the  bag  opened 
are  inserted  only  when  the  bag  is  used  alone  ;  when  the 
bag  is  attached  to  the  frame  these  bamboos  are  removed 
and  the  tags  of  cloth  knotted  to  the  frame,  so  that  the 
bag  can  be  at  once  removed  and  twisted  up.  In  place  of 
bamboo,  strips  of  wood  may  be  used. 

The  Hand  Net. 

Cut  a  Y  piece  (of  guava,  jamun  or  litchi  wood),  the 

stem  six   inches  long  and  about   three   quarters  of  an 

inch  in  diameter,  the  arms  four  inches  in  length  and  half 

an  inch  in  diameter  :  two  hollow  bamboos  six  inches  long, 

the  bore  a  little  larger  than  the  arms  of  the  Y  so   that 

they  fit  tightly  :  a  green  bamboo  slip,  five  feet  two  inches 

long,  half  an  inch  in  diameter.     These  fit  together  as  in 

the  diagram  and  make  the  net  frame. 

For  the  net  take  two  pieces  of  muslin,  each  two  feet  seven  inches  square  ;  turn 

over  one   inch   to   make  a  hem,  cut  each    piece   along  the   thick   black   line  of  the 

diagram  and  sew  the  cut  pieces  together  along  this  line,  not  along  the  double  hem.     Sew 

on    to  the  hem  a  piece  of  cloth  one  inch  wide  to  pass  the  bamboo  through.     The  long 


Fig.  C. 
Rough  net  frame  in  pieces. 


Fig.  D, 

Muslin  piece  for  hag. 
(Cut  two  pieces  to  sbape  shown  and  join  along  curved  edges.) 

bamboo  is  then  passed  through  the  cloth  bag,  and  inserted  at  each  end  into    the   tubular 
bamboos  which  are  fixed  to  the  Y, 

P 


APPENDIX  B. 


^J 

-J 

P 
.i 

1 

lif     'V 

Fig.  E. 

How  to  pin  a  Beetle. 


COLLECTING,  PINNING,  SETTING. 

THERE  is  possibly  no  better  field  for  the  student  of  insects  tban  India ;  tbe  variety 
of  climate,  of  vegetation  and  of  physical  features  means  enormous  number  of 
species  of  insects,  which  flourish  each  under  the  conditions  suited  to  them.     At  all  times 

of  the  year  insects  are  to  be  found  at  work,  and  those 
who  specially  study  one  group,  as  also  those  who  are 
interested  in  insect  life  as  a  whole,  will  always  find 
abundance  of  material  at  hand. 

It  is  nnfortunate  that,  as  elsewhere,  the  study  of 
one  sub-order,  the  Butterflies,  has  occupied  so  large  a 
share  of  the  work  of  the  Naturalist  in  India.  If  the 
attention  given  to  this  group  had  been  more  equally 
distributed  over  the  insect  world,  there  would  be  a  far 
wider  knowledge  of  the  insects  as  a  whole.  In  spite  of 
the  volumes  on  butterflies,  moths,  plant  bugs,  bees  and 
wasps,  the  insect  world  of  India  is  very  little  known. 
The  beetles  are  almost  untouched  ;  the  grasshoppers, 
crickets,  mantids,  stick  insects  and  other  Ortlioptera 
have  been  little  worked  at ;  and  there  is  little  on  record 
in  regard  to  flies  and  the  smaller  species  of  plant  bugs 
and  sucking  insects.  This  refers  only  to  their  collection  and  classification.  In  the  far 
wider  field  of  biology  how  little  is  recorded ;  with  an  almost  unparalleled  variety  in  the 
insect  world,  there  is  little  known  of  the  life  histories,  the  habits,  the  beautiful 
adaptations  of  even  the  common  insects.  The  writings  of  E.  H.  Aitken  illustrate 
what  a  splendid  field  there  is  for  simple  observation  and  study  of  the  manners  and 
habits  of  the  most  familiar  insects  ;  and  in  the  present  state  of  our  knowledge,  the  wider 
problems  of  distribution,  relation  to  climate,  migration,  etc.,  cannot  be  entered  upon. 

There  is  abundant  work  in  every  group,  work  not  less  interesting  in  biology  or  in 
the  study  of  less  popular  groups  than  that  which  has  been  done 
for  butterflies.  The  condition  of  the  collections  at  the  Indian 
Museum,  the  pages  of  the  Asiatic  Society  and  Bombay  Natural 
History  Society's  Journals  illustrate  the  very  scanty  nature  of 
the  recorded  work  on  Indian  insect  life,  and  it  is  assuredly 
within  the  reach  of  every  observer  to  add  to  this  knowledge  and 
cany  on  the  work.  It  is  needless  to  enlarge  on  the  value  of 
this  work  ;  those  who  study  Nature  do  not  consider  the  value  of 
what  they  do  but  find  an  added  joy  in  life  in  their  work  ;  they 
then  find  it  impei-ative  in  the  interests  of  all  naturalists  to  put 
on  record  what  they  have  done  and  help  to  build  up  the  fuller 
history  of  the  insect  world. 

In  the  entomologist's  world  at  present,  systematic  work,  that  is  classification 
and  nomenclature,  engrosses  a  far  too  large  portion  of  the  study  devoted  to  the  subject. 
Qf  the  thousands  who  study  and  write  about  classification,  there  are  but  tens  wl^o 


Fig,  F. 
A  pinned  Bug. 


COLLECTING. 


%n 


Fig.  G. 

A  pinned  Moth, 

wings  closed. 


turn  to  the  wider  problems  of  biology  or  oven  to  the  simpler  work  of  "  life  histo* 
ries."  In  India,,  where  entomological  work  is  little  carried  on,  I  would  plead  the 
necessity  of  life  history  work,  or  if  systematic  work  is  essential,  at  least  the  study  of 
groups  less  known  than  the  butterflies.  In  the  popular  mind, 
entomology  is  "butterflies,"  whereas  the  butterflies  are  not 
one-twelfth  of  the  known  insect  world  and  are  probably  not  one- 
fiftieth  of  the  actual  species  of  insects  now  existing.  Their 
beauty  and  large  size  impress  them  on  our  minds ;  but  they  are 
from  some  points  of  view  the  least  attractive  group,  as  they  are 
almost  without  exception  the  least  important  in  their  influence 
on  agriculture  and  man's  welfare.  To  the  systematist,  the  beetles 
and  the  flies  offer  unrivalled  fields  of  work,  both  little  touched  as 
yet  and  in  both  of  which  very  valuable  work  has  yet  to  be  done 
before  the  classification  of  these  orders  can  be  fully  carried  out. 
The  mantids,  crickets,  cockroaches,  grasshoppers,  and  other  Orthop' 
tera  have  been  barely  touched,  from  the  biological  as  from  the  systematic  side. 
Myrmeleonides,  Maniispides,  Hemerobiids  and  other  Neuroptera  are  far  commoner 
in  India  than  in  some  parts  of  the  world,  and  there  is  a  splendid  field  here  for  life 
history  work.  The  insect  life  of  fresh  water,  of  the  streams,  ponds,  tanks  and  lakes 
has  not  been  entered  upon  and  would  yield  most  valuable  results.  A  very  slight 
attention  paid  to  scale  insects  has  yielded  much  that  is  new,  and  the  smaller  species  of 
plant  bugs  are  found  in  very  great  variety  everywhere.  There  is  no  lack  of  absorbing 
work  and  there  should  be  no  lack  of  workers  in  a  country  where  so  many  have  to  find 
their  own  interests  and  hobbies,  and  live  surrounded  by  the  marvellously  varied  insect 
world.  The  naturalist  in  India  has  two  great  advantages  not  to  be  found  everywhere. 
Publication  is  easy  in  the  pages  of  the  Asiatic  Society  or  Bombay  Natural  History 
Society's  Journal,  which  bring  the  work  before  an  appreciative  audience ;  the  Indian 
Museum  is  there  to  help  and  is  glad  to  receive  specimens  which  are  then  part  of 
what  I  may  call  the  National  Indian  Collection,  and  really  part  of  the  National 
Collection  gathered  at  the  British  Museum  of  Natural  History  in  South  Kensington. 
Through  the  Indian  Museum,  the  help  of  the  workers  in  the  British  Museum  is 
readily  obtained,  and  the  Indian  Museum  reference  collections,  though  not  complete, 
have  been  worked  on  by  the  leading  European  specialists. 

Collecting. 

In  the  popular  mind,  an  entomologist  is  a  temporarily  insane  person,  usually  hot, 
flushed  and  panting,  who  careers  wildly  after  butterflies  armed  with  a  large  net. 
The  real  entomologist  is  probably  to  be 
found  in  the  fields,  with  no  net  or  other 
appliances  except  a  few  pill  boxes,  a  knife 
and  a  good  lens.  Collecting  differs  accord- 
ing to  the  group  to  be  collected ;  those 
who  want  to  know  the  ways  and  habits 
of  the  common  insects  will  spend  hours  out 
in  the  open  simply  watching.  The  best 
knowledge  of  the  insect  fauna  of  a  district 
is  got  by  patient  watching.  As  soon  as 
a  particular  species  becomes  quite  familiar 


Fig.  H. 
A  finned  Moth,  wings  set. 


u2 


29^  APPENDIX    B.       COLLECTING,    PINNING,   SETTING. 

one  collects  perhaps  two  of  each  sex  for  purposes  of  identification.  As  time  goes  by 
one  gets  to  know  the  ways  and  habits  of  all  the  common  insects  and  gradually 
acquires  a  real  knowledge  of  the  fauna  of  the  district.  This  is  the  thorough  and 
intimate  knowledge  which  enables  one  to  know  why  an  insect  is  in  a  particular  spot, 


Fig,  I. 

The  Lemon  Butterfly.    To  show  setting  of  wings,  the  hind  margin  offorewing  at  right 

angles  to  the  body. 

what  it  is  doing  and  what  its  life  is.     This  is,  to  the  writer  at  least,  the  real  work  of 
the  entomologist.     It  is  then  easy  to  collect  all  available  specimens  of  any  one  group 
and  the  actual  collection  is  subordinate  to  the  field  work,  that  is,  is  simply  an  index 
to  the  knowledge  acquired  of  the  local  insect  life.     With  that  index,  one  can  sit  down 
and  write  the  experiences  for  the  benefit  of  the  entomological  world,  and  there  would 
then  be  a  speedy  advance  in  our  knowledge  of  the  insects  of  the  country.    As  an  out- 
come of  this,  the  study  of  a  particular  group  can  be  taken  up,  and  the  work  extended 
over  a  large  area.     This  then  becomes  a  valuable  piece  of  work,  valuable  in  proportion 
as  it  is  based  on  thorough  familiarity  with  the  insects  of  one  district  and  on  the  whole 
life  of  the  insects  in  question,  not  simply  their  external  stnicture  or  the  venation  of  the 
wings.     The  tendency  to  commence  straight  away  on  the  study  of  one  group  is  deplor- 
able ;  it  leads  to  purely  systematic  work,  counting  the  spines  on  the  margins  of  the 
tibijB  or  the  hairs  on  the  pygidium,  and  there  is  no  basis  for  comparative  work  and  no 
understanding  of  the  enormous  value  of  biology.     The  study  of  dried  insects  is  not 
entomology  ;   it  is  but  a  small  part.     Tield  work,  involving  more  than  mere  collecting, 
is  the  backbone  of  entomology,  and  the  last  thing  really  wanted  is  the  name  of  the 
insect,  whereby  to  find  out  what  others  have  said  about  it.     Collecting,  therefore.^varies 
with  the  aims  of  the  entomologist,  and  becomes  an  entirely  different  thing  as  he  is 
intent  on  different  aims.     To    the  student  of  each  group,   different  appliances  are 
necessary ;   to  the  beginner,  to  the  naturalist  pure  and  simple  who  wants  to  know  the 
insects  of  his  district,  the  solo  requirements  are  boxes,  a  knife,  a  lens,  and  perhaps  a 
pet  and  killing  bottle, 


eOLiikcTlNGl. 


^93 


The  boxes  most  useful  are  card  boxes  with  a  glass  bottom  {not  top).  They  can 
be  bought  or  are  made  by  the  North  West  Soap  Company.  Calcutta.  At  a  pinch 
old  match-boxes  are  very  good.  A  strong  knife  is  liandy  for  digging  and  for  extract- 
ing "borers."  A  lens  is  absolutely  necessary,  and  is  best  got  from  London  or 
Gemany.  I  prefer  Leitz's  apknatics,  magnifying  10  or  16  diameters,  but  there  are 
many  patterns  of  aplanatic  and  Steinheil  lenses  that  are  equally  good.  The  handiest 
net  i  know  of  is  the  so-called  kite  or  balloon  net  (fig.  E,  page  302),  made  of  four  pieces 
of  cane,  a  brass  Y  and  a  bag  of  green  muslin.  Killing  bottles  vary  for  different  groups, 
but  the  cyanide  or  B.  C.  bottle  is  best  for  general  work. 

It  is  impossible  to  say  anything  in  detail  of  special  collecting  in  each  group. 
Aptera  are  got  by  careful  search  in  decaying  vegetation,  bark,  under  leaves,  in  all 
soi-ts  of  nooks  and  odd  places.  A  camel-hair  brush  and  a  bottle  of  absolute  alcohol  or 
95  %  spirit  is  the  best  way  to  secui-e  specimens  unhurt,  unless  they  be  taken  home  alive 
with  some  damp  material  in  a  box.  The  absolute  alcohol  and  brush  secures  perfect  speci- 
mens of  the  active  Campodea  or  Collembolaiovms,  and  they  die  rapidly  in  the  alcohol. 

Or^Aoi>#em  vary  with  the  family.  Earwigs  are  found  on  the  ground  in  woods  or 
in  flowers.  Cocki-oaches  under  leaves  or  among  low  plants  or  on  the  bark  of  trees. 
Mantids,  Phasmids,  Grasshoppers,  in  crops,  on  plants,  on  bushes.  Crickets  among 
fallen  leaves,  in  bushes,  in  the  ground,  etc.  A  net  is  useful  for  grasshoppers,  but  sharp 
eyes  and  hands  are  all  that  the  other  families  require. 

Neuroptera  want  a  net  ;  dragon-flies  are  everywhere ;  Bemerobiids  are  on  crops 
chiefly  or  among  bushes  under  trees  ;  Myrmeleonides,  Mantispides,  Ascalaphides 
under  trees  out  in  the  sun.  Perlids,  Sialids,  Ephemerids  and  Caddisflies  near 
fresh  water.  Termites  in  their  nests  or  at  lights.  Emhiids  come  to  lights.  Psocids 
are  on  trees  and  bushes.  Ilallophaga  on  birds,  etc  There  is  a  big  range  for  the 
Neuroptorist  and  an  almost  unexplored  one. 


Fig.  J. 

A  pinned  Vragon-fiy  (Neuro'ptera). 


Eymenoptera  distinctly  want  a  net  in  most  cases,  and  far  more  necessary  than 
collecting  is  the  patient  watching  and  breeding.     Benzene    is    a    peculiarly    good 


294 


AtPENDIX   B.      COLLECTING,   PINNING;   SETTING. 


killing  agent,  a  little  vapour   being  snfficient.    Chloroform  should  not  be  used  as  it 
turns  yellow  to  red  in  many  cases. 

They  are  far  too  large  a  group  to  attempt  any  summary  of  and  they  can  be  caught 
from  early  morning  to  sunset,  and  in  the  evening  are  often  easily  captured  asleep  on  plants. 

Coleoptera  again  are  far  too  large  to  deal  with.  Every 
family  wants  separate  collecting.  In  this  group  no  chance 
of  rearing  from  the  grub  should  be  lost.  So  little  is  known 
and  the  difficulties  are  so  great  that  one  may  look  on  a 
reared  beetle  as  something  of  an  achievement  and  hasten  to 
put  the  facts  on  record.  This  of  course  does  not  refer  to 
household  plagues  which  rear  themselves  far  too  easily  in 
cheroots,  flour,  etc. 

Carcases  may  be  mentioned  as  a  good  bait,  however 
small  they  are,  and  droppings  of  any  kind  yield  many 
varieties,  as  does  the  bark  of  old  trees.  Benzene  or  cyanide 
are  excellent  for  killing,  and  no  hai'm  is  done  by  immer- 
sion in  benzene. 

Lepidoptera  have  fortunately  demanded  breeding  as  a 
necessity  of  good  specimens,  hence  we  know  the  life 
histories  and  caterpillars  in  many  cases.  The  adventitious 
aid  of  "  sugaring,"  and  of  lights  and  light  traps,  enable 
the  moth-hunter  to  secure  many  treasures.  Chloroform  or 
cyanide  is  best  for  killing,  not  benzene. 

Diptera  need  a  net,  or  better  still,  are  easily  reared 
when  the  grubs  are  got.  Grubs  live  in  all  sorts  of  places 
and  there  is  no  more  widely  diffused  or  more  interesting 
group  than  this.  For  variety  of  habits  and  habitat,  the  fly 
grubs  are  fully  equal  to  the  beetles  and  beetle  grubs,  and 
are  more  easily  I'eared.  The  collector  will  find  them  every- 
where, on  the  wing  or  as  grubs.  For  killing  I  prefer  a  dry 
tube  and  a  benzened  cork.  Have  a  dozen  tubes  of  one  size, 
corked,  one  containing  benzene.  Capture  your  fly,  transfer 
to  a  clean  dry  tube,  and  then  holding  your  thumb  over  the 
mouth  of  the  tube  transfer  the  cork  of  the  benzene  tube  to 
the  tube  with  the  fly  in  and  replace  by  the  clean  cork.  The 
fumes  of  benzene  from  the  cork  will  then  speedily  kill  the  fly.  Flies  must  never  be 
wetted  with  any  liquid  whatever. 

Hemiptera  can  be  killed  in  any  fashion  if  they  are  big  and  hard.  Soft  ones  may 
need  to  be  preserved  in  formalin,  as  all  Aphidce  (Green-fly),  etc. 

A  net  is  hardly  needed  for  most  Hemiptera.  Plant  bugs  are  rarely  very  active. 
Scale  insects  and  mealy  wings  can  only  be  collected  on  their  food-plants  and  special 
attention  has  to  be  paid  to  rearing  adults,  parasites,  etc.  Sharp  eyes  are  needed  for 
collecting  Hemiptera  and  not  much  more.  •^ 

The  above  summary  may  help  the  beginner,  but  will  not  help  the  sj^ecialist  in  any 
order.  Every  naturalist  finds  his  own  methods;  lam  satisfied  with  the  benzened 
cork  tubes  for  a  killing  bottle,  a  knife,  a  lens,  and  a  supply  of  boxes.  If  I  am  hunt- 
ing J!feuroptera  or  grasshoppers  or  wasps,  I  take  a  net.  When  a  special  group  is  to 
be  studied,  I  use  such  special  methods  as  my  gcaieral  experience  has  taught  me  suit 


Fig.  K. 

Fly  pinned  on  disc  (above) . 

Ichneumon  and  moth 

pupa  case  from  which  it 

emerged,  on  one  pin. 


SE1"TIKG. 


291 


that  gronp,  but   it   serves  no   useful   purpose  to  expound  special  methods  which  arc 
familiar  or  unsuited  to  those  who  work  on  special  groups. 

Killing. 

The  entomologist  must  have  good  killing  methods,  or  his  specimens  are  useless. 
The  ordinary  cyanide  bottle  is  good  and  precautions  must  be  taken  to  keep  it  dry 
inside. 

I  prefer  a  mixture  of  benzene  and  chloroform  in  equal  parts,  with  a  few  drops 
of  citronella  or  bergamot  oil  added.  (B.  C.)  A  wide-mouthed  bottle  with  wads  of 
blotting  paper  damped  with  this  mixture  Is  very  good,  and  I  find  it  suits  all  groups 
equally  well. 

For  laboratory  material  or  for  dissecting,  heat  or  absolute  alcohol  give  good  results 
for  most  insects. 

Tobacco  smoke  will,  If  nothing  else  be  available,  kill  many  small  insects ; 
Hymenoptera  especially  curl  up  almost  at  once. 

Setting,  Pinning,  Mounting. 

Having  killed  one's  specimens,  the  next  thing  is  to  set  them.  There  again  a 
treatise  Is  required  to  cover  all  the  special  methods,  and  no  attempt  is  made  to  do 
more  than  outline  the  subject.  Experience  and  many  failures  teach  more  than  a 
volume  can  do,  and  many  specimens  must  be  ruined  before  this  can  be  mastered. 

Pins  are  of  various  kinds.  The  ordinary  insect  pin,  white  or  enamelled  black, 
is  the  best,  and  one  may  use  them  entirely  or  use  Carlsbad  or  long  American  pins. 
Steel  pins,  enamelled  black,  are  not  reliable  as  the  enamel  comes  off  and  the  pin  rusts 
through.  D.  F.  Tayler  or  Kirby  Beard  &  Co.  make  ordinary  pins  and  Taylor's 
Nos.  2,  3,  7, 12, 16  and  20  cover  practically  all  needs.  In  pinning,  the  point  is  to  have 
one-third  of  one's  pin  above  the  insect  and  the  rest  in  and  below  it.  It  is  usual  to  pin 
Ortkoptera  in  the  middle  of  the  thorax  or  through  the  right  wing;  Neuroptera, 
Hymenoptera,  Lepidopfera  and  Hemiptera  through  the  thorax  ;  Coleoptera  through 
the  right  wing-case  so  that  the  pin  does  not  pierce  the  right  hind  leg. 

Small  insects  are  often  very  troublesome  to  mount  and  set,  and  there  are  special 
methods  for  them. 

Staging  consists  in  pinning  the  insect  with  a  fine  pin  on  a  slip  of  polt/porus  pith  ; 
the  pith  Is  then  pinned  with  a  big  pin.     Any  compact  white  pith  will  do. 


Fig.  L. 

Locusiipaclced  inljpajperlcylinilerl 

Gumming  consists  of  fixing  the  insect  to  a  slip  of  card,  and  pinning  that  with  a 
big  pin.  White  gum  is  used,  as  little  as  possible  being  taken.  The  cards  used  here  are 
rectangular,  as  narrow  as  possible  ;  others  prefer  triangular  points. 


296 


APPENDIX    B.      COLLECTIffG,    PIMNI>TG,    SETTING. 


On  Cord. — This  is  a  method  of  pinning  flies  ;  a  disc  of  card  is  taken,  cut  with  a 
20-bore  gun-wad  punch,  and  a  fine  (No.  20)  pin  passed  through  ;  the  pin  is  then 
carefully  pushed  through  the  thorax   of  the  fly  from  below,  so  that  the  point  projects 

above.     The  card  is  then   pinned  with 


Fig.  M. 

Paper  cut  for  folding. 


a  big  pin  in  the  opposite  way  (fig.  K). 

The  last  method  is  used  only  for 
Diptera  ;  gumming  is  used  for  small 
Coleoptera ;  staging  for  small  Or- 
thoptera,  jSeuroptera,  Hymenoptera, 
medium  Coleoptera,  and  for  Hemip- 
tera.  Small  Lepidoptera  require  special 
pins. 

Many  very  small  insects  can  only 

be    kept    in    small  corked  tubes ;  the 

inside  of    the    corks    should    then    be 

dipped  in  a  solution  of  naphthalene,  in 

benzene,  or  in  carbolic  acid. 

Relaxing  consists  in  keeping  the  specimen  for  12  hours  or  more  in  a  damp  box  till 

rigor  mortis  has  passed  ofi"  and  the  wings,  legs  and  antenniB  are  flexible.      A  small 

quantity  of  acetic  or  other  acid  in  the  box  helps  to  preserve  the  colour. 

Setting   Lepidoptera   requires   setting  boards   and   one   may   adopt  any   of  the 
methods,  high  setting  being  perhaps  the  best  after  the  manner  of  the  British  Museum. 
Other  groups  when  pinned  should  have  their  legs  and  antennaj  carefully  arranged 
so  as  to  be  natural  and  so  as  to  be  readily  examined  by  a  lens. 

Once  an  insect  is  mounted  and  dried,  it  is  brittle  and  cannot  easily  be  reset,  so 
the  arrangement  of  the  legs,  antennse  and  wings  is  important.  Specimens  should  be 
as  natural  as  possible.  The  wings  of  Neuroptera  should  be  spread  as  in  the  case  of 
Lepidoptera.  In  grasshoppers  the  left  wings  of  one  specimen  should  bespread.  Speci- 
mens should  be  set  in  different  ways,  some  with  wings  open,  some  with  wings  as  they 
are  normally  when  at  rest,  the  object  being  to  display  the  insect  and  to  preserve  its 

natural  habit  of  body.     Having  set  the  speci- ^__ 

mens,  dry  them.    No  insect  should   be   stored  i  .  ■  ■    i 

till  it  is  perfectly  dry  and  the  lack  of  this 
means  a  certainty  of  moulds  sooner  or  later. 
In  the  monsoon,  a  proper  drying  box  contain- 
ing calcium  chloride  or  lime  is  very  valuable, 
if  not  essential. 

Labelling. 

A  specimen  without  a  label  may  be  thrown 
Eiway,  as  it  is  useless.  Labelling  should  be 
done  at  once  as  there  will  then  be  no  confusion. 
It  would  be  a  good  thing  if  all   entomologists 

labelled  in  the  same  way,  and  the   best  system  „       -j^ 

of  labelling  is  as  follows  :—  Moth  or  Butterfly  in  paper. 

The  labels  used  ai-e  of  stout  white  paper  or  thin  card  ;  the  number,  date  of  capture, 
name  of  food-plant,  and  locality  are  written  on  the  label  and  at  one  side  the  name 
of  the  collection.    The  collector's  name  is  on  a  separate  label  if  the  specimen  is  sent  to 


__L._ 


SToiiiNG.  got 

the  Museum,  and  all  Museum  specimens  bear  tlie  Museum  label.  In  puttinj,'  locality 
one  must  be  precise.  The  village,  taluka,  or  town,  the  province,  and  "  India  "  must  all 
be  placed  on  the  label,  as  a  specimen  labelled  "  Hyderabad"  may  be  from  one  of  two 
places,  and  the  entomologist  in  Europe  or  America  to  whom  a  specimen  may  go  does 
not  necessarily  know  that  these  places  are  in  India. 

Labelling  like  setting  is  done  with  a  view  to  posterity,  and  collections  now  made 
may  be  in  a  Museum  for  centuries  and  may  go  to  any  part  of  the  world  eventually. 

If  the  insect's  name  is  to  be  on  a  label,  it  should  be  on  a  separate  label  of  a  distinc- 
tive colour.  There  may  then  be  three  labels,  the  collector's  name,  the  full  details  on  a 
collection  label,  and  the  name  of  the  insect,  with  the  name  of  the  person  responsible 
for  naming,  followed  by  an  exclamation  point ! 

Storing. 

Insects  after  being  pinned,  labelled  and  set  are  stored  in  corked  boxes.  Boxes 
must  be  air-tight  and  well  corked  and  papered. 

Naphthalene  or  other  "  insectifuges  "  must  be  placed  in  the  box.     The  difficulty  in 

India  is  not  excluding  insects   so    much    as    exclud-  "^  _" 

ing  damp,  and  it  is  at   this  time  that   the    value   of      V'^'^^w.  5>9  S6JS.-JS!a 

drying  insects  thoroughly  is  apparent.     Any  moisture  \       ^^^^' ^i^.,<«,  ■ 

in  the   insect   leads   to  mould   when   the   atmosphere  \    ^^'^^ie>^ 

round  it  is  moist  also,  and  the  surest  guard  against 
mould  is  thorough  drying  before  placing  in  the  store 
box. 

Jt  is  unnecessary  to  pin  all  of  a  collection  if  there 
are  duplicates.  Spare  Lepidoptera  are  best  kept  in 
"  papers,"  spare  Orthoptera  in  cylinders  (6g.  L),  and 
spare  beetles  in  sawdust  or  bran.  They  can  then  be 
relaxed  and  set  if  wanted  for  the  pinned  collection,  or  pjg  q 

are  readily  sent  by  post  unpinned.  The  finished  paper. 

Caterpillars,  etc. 

Larvae  of  all  kinds  are  best  preserved  in  alcohol,  alcoholic  mixtures,  or  formalin. 
Special  methods  must  be  used  for  obtaining  laboratory  material  for  dissection,  etc. 
Kectitied  spirit  of  70  per  cent,  alcohol  is  the  best  form  of  spirit  ;  a  mixture  of  alcohol, 
spirit  and  glycerine  preseiTCS  larvae  well  and  keeps  them  in  a  good  flexible  state. 
Caterpillars  are  best  blown  with  a  larva  blowing  apparatus  or  over  a  spirit  lamp  and 
small  oven.  A  solution  of  4  per  cent,  formalin  in  water  is  good  for  most  laiTie.  A 
handy  way  of  storing  larvae  is  in  tubes,  3  inches  long  by  1  inch  in  diameter,  with  a 
good  cork.  The  label  should  be  inside  the  tube  wi-itten  with  hard  pencil  or  good  ink, 
and  it  is  useful  to  have  the  insect's  number  on  the  cork  or  on  the  outside  for  ready 
reference. 

Arrangement  of  Collection. 

In  making  a  collection  of  pinned  insects,  the  difficulty  lies  in  allowing  for  expan- 
sion.  However  much  room  one  allows  for  future  specimens,  one  cannot  be  sure  that 
the  arrangement  will  meet  future  needs  simply  because  one  cannot  foresee  what  will 
come  in.  It  is  perhaps  best  to  allow  at  first  for  a  small  expansion  only  and  then  pre- 
sently transfer  the  whole  collection,  leaving  a  large  space  for  fresh  accessions.  Where 
all  families  are  collected,  it  is  Well  to  start  a  box  for  each  ol'der,  expanding  these  orders 


298  APPENDIX   B.      COLLECTING,    PINNING,   StlTTlN^. 

into  boxes  assigned  for  each  big  family  and  groups  of  small  ones.  For  this  reason 
store-boxes  are  better  for  keeping  permanent  collections  in  than  cabinets  with  drawers, 
as  new  boxes  can  be  put  in  anywhere  and  new  drawers  cannot  always  be  inserted. 

In  making  a  general  collection  it  is  wiser  to  separate  the  orders,  and  not,  for 
instance,  to  put  the  parasites  of  a  species  of  moth  with  the  specimens  of  that  moth. 
If  the  moths  are  the  object  of  the  collection,  then  the  parasites  can  fitly  be  placed  with 
the  species  they  prey  on. 

It  is  important  to  put  name  labels  on  the  pins  and  not  simply  below  each  species ; 
there  may  be  a  generic  label  at  the  head  of  a  genus  and  a  specific  label  below  each 
species  in  addition. 

Special  Material. 

All  specimens  cannot  be  either  pinned  or  in  spirit ;  there  must  be  a  quantity  of 
special  material  unsuitable  for  either.  Eggs,  pupa  cases,  cocoons,  specimens  illustrat- 
ing the  habitations  of  insects  must  be  kept  separate  in  boxes  or  bottles  as  a  rule.  For 
small  objects,  eggs,  pupa  cases,  small  cocoons,  etc.,  glass  topped  boxes  are  useful.  A 
small  quantity  of  naphthalene  helps  to  preserve  them.  Duplicate  insects  also  want 
special  storing,  as  the  Lepidoptera  in  papers,  Coleoptera  in  sawdust,  Orthoptera  in 
cylinders.  Coccidm  keep  well  in  small  envelopes  wrapped  in  oiled  paper,  as  do  the 
pup£E  and  larvfe  of  Alcurodidce.  Small  Hemiptera,  Kymenoptera,  Dlptera,  can 
often  be  best  kept  in  good  corked  tubes,  as  can  small  duijlicate  Coleoptera  ;  but  they 
must  first  be  well  dried,  and  the  outside  of  the  corks  should  be  varnished  or  dipped 
in  melted  paraffin  wax.  A  dry  specimen  should  always  be  in  an  atmosphere  of  naphtha- 
lene or  carbolic  acid ;  the  inside  of  corks  of  tubes  should  be  dipped  in  carbolic  acid  or  in 
a  solution  of  naphthalene. 

In  working  microscopic  specimens,  a  series  of  slides  accumulates  of  insects  in 
Canada  balsam.  These  are  kept  in  special  cabinets  and  it  is  convenient  to  numbar 
them  in  order  as  they  are  made  and  list  them  separately  in  a  book. 

Rearing. 

A  volume  could  be  written  on  this  subject  to  deal  with  the  difEerent  families  and 
their  peculiar  needs.  There  is  but  one  rule,  to  keep  the  insects  as  much  as  possible  in 
natural  conditions.  This  can  never  be  fully  attained  in  a  small  space  or  even  in  the 
biggest  cage  indoors.  Many  cannot  be  reared  in  captivity  save  under  exceptionally 
good  conditions ;  others  will  live  under  very  bad  conditions.  Lepidoptera  are  among 
the  easiest  unless  they  are  such  as  some  of  the  LtjccBnidce,  which  miss  the  attendance 
uf  their  particular  species  of  ants.  Plant-feeding  caterpillars  want  plenty  of  fresh 
food,  proper  conditions  of  light,  air  and  moisture,  and  whatever  particular  conditions 
they  require  for  pupation. 

Diptera  are  often  easy,  provided  they  are  not  allowed  to  dry  up.  Most  predaceous 
forms,  MantidcB,  Hemerohiidce,  Coccinellidce,  need  a  very  large  supply  of  food  and 
even  then  are  not  always  easy  to  rear. 

Larger  plant-sucking  Hemiptera  need  live  plants  to  feed  on  and  then  thrive  ^very 
often.  Smalhu-  Hemiptera  are  easy  to  rear,  save  such  forms  as  Jassidce,  Many 
species  of  Orthoptera  can  be  reared  but  will  not  breed  in  captivity  ;  the  same  is  true 
of  the  majority  of  Coleoptera  and  Hemiptera. 

Aquatic  insects  demand  special  methods  usually  easily  obtained  if  the  insects  are 
accustomed  to  stagnant  water  but  almost  impossible  for  such  as  live  in  swiftly  run- 
ning  water. 


Ij  Ha  RING. 


^gd 


Boring  Iiuccts  are  easy  to  rear  but  will  not  breed  readily,  unless  they  are 
Lepidoptera.  Galls  are  exceptionally  difficult  to  manage,  and  I  have  found  Dr.  Sharp's 
suggestion  of  always  having  a  little  carbolic  acid  to  vapourise  in  the  jar  or  cage  a 
good  one. 


Fig.  p. 
Field  cage,  three  feet  cuhe. 

For  breeding  cages  and  jars,  there  is  no  standard.  For  small  insects  cages  made 
of  perforated  zinc  with  a  sliding  glass  lid  are  very  good,  and  are  also  handy  for 
travelling.  From  these  up  to  cages  6  feet  high  there  may  be  an  indefinite  series 
according  to  the  object  in  view.  Many  small  species  need  nothing  more  than  a  glass- 
topped  box  or  a  glass  jar. 

Cleanliness,  plenty  of  fresh  food,  a  liberal  provision  of  air,  ligbtj  dry  or  damp 
earth  and  shelter  are  the  chief  things  to  be  looked  for  in  rearing  insects. 


Notes* 

It  is  a  sound  plan  to  Work  entirely  by  numbers,  giving  each  species  a  serial  num* 
bel*  and  using  that  for  all  specimens  of  that  species,  and  for  all  notes.  All  the  records 
concerning  pests  are  kept  by  numbers  and  the  various  species  ai'e  known  by  numbet 
throughout.  This  rarely  entails  confusion  when  two  closely  allied  species  ai'e  confused 
under  one  number,  and  even  this  can  be  avoided  by  giving  a  fresh  number  to  a  new 
batch  of  what  one  thinks  may  bo  a  familiar  species,  till  one  is  sure  it  is  tJie  same. 
No  harm  is  done  by  having  one  species  under  several  numbers  till  one  is  sure  they  afe 
the  same,  as  it  is  an  easy  matter  to  put  them  all  under  one  number  at  any  time. 

Notes  habitually  and  regularly  taken  include  field  notes,  notes  from  rearing  cages, 
notes  of  specimens  sent  in,  notes  froin  literature,  and  a  note  of  all  the  specimens  that 


300 


APPENDIX    B.       COLLECTING,    PINNInG,    SETTlNGt. 


are  in  the  collection  relating  to  that  one  species.  By  bringing  these  all  together  in 
one  place  one  has  at  a  glance  the  whole  history  of  each  species  so  far  as  it  is  known. 

A  separate  index  of  food  plants  and  a  systematic  index  then  become  necessary  so 
that  one  may  at  a  glance  find  all  the  pests  of  a  particular  crop,  or  all  the  insects  of  a 
particular  family  that  one  has  in  the  collection. 

I  prefer  to  keep  nearly  all  this  information  on  cards,  in  a  card  catalogue  series,  and 
only  rearing  notes  and  field  notes  are  entered  separately  and  then  condensed  on  to  the 
regular  card  series.  The  methodical  collection  of  all  information  is  a  great  part  of  any 
continuous  entomological  work,  and  for  lack  of  it  a  great  deal  of  work  has  been  lost. 
I  have  not  space  to  describe  the  card  system  in  use ;  I  am  convinced  that  methodical 
and  careful  note  taking  is  of  the  greatest  importance  if  one  aims  at  anything  higher 
than  a  mere  collection  of  dried  specimens.  The  most  trivial  things  may  later  on  be 
found  to  be  of  the  utmost  importance,  and  one  racks  the  memory  in  vain  to  remember 
the  precise  details. 


Formulse. 


l.—B.  C.  bottle. 


Benzene     . 
Chloroform 


Absolute  alcohol 
Glacial  acetic  acid 


■)  Equal  parts.  Add  a  few  drops 
>  of  oil  of  bergamot  or  other 
)      essential  oil. 


Killivg  fluid  for  Aptera 


Equal  pai'ts. 


Formalin, 
Formic  aldehyde  40%  (Formol)      1  part. 


Water 


White  gum  arable 
White  gum  tragacautli 


1 9  parts. 
Cement. 


In  equal  parts,  powdered,  with 
enough  water  to  make  a  paste, 
and  a  few  drops  of  carbolic  acid. 


Aluminium  sulphate 
Water         . 
Gum  arable 
Water 
W  ix  the  two. 

Alcohol,  95% 
Glycerine   . 
Water 


Gum  for  labelling  glass  bottles. 

2  grams  •)  dissolve. 
20  grams  ) 
.         74  grams  ■Jjjj^^^^^,^^ 
180  grams  ) 


Preserving  fluid. 

"  ^        ^  Add  \  per  cent,  of  acetic  acid  to 
1    part  >      fiiiiahed  mixture. 
1    part  ^ 


Cyanide  of  potassium 
piaster  of  Paris    . 


2. — Killing  bottle. 

.     1  oz. 
.         .         .         .         .         .     4  oz. 

Place  the  cyanide  in  the  bottle,  cover  with  half  the  plaster.  Mix  the  rest  of  the 
plaster  to  a  cream  with  water,  and  quickly  pour  over  the  dry  plaster  and  cyanide  in  tha 
bottle. 


APPARATUS, 


301 


Apparatus. 

J^ets. ^The  ordinary  kite  or  balloon  net  serves  most  purposes,  but  a  small  ligbt 

net  with  a  bag  of  ligbt  material  may  be  needed  for  small  Hymenoptera,  Dipteral 
etc. 


Fig.  Q. 
Frame  0/  hiie  net,  of  cane  with  brass  ends. 


For  aquatic  insects,  a  stout  net,  inside  lined  with  fine  muslin  and  outside  with 
coarse  holland,  with  a  bottle  at  the  bottom  is  most  suitable. 

Pill  bojres.—¥ov  collecting  these  should  be  glass  bottomed,  round,  nested  boxes, 
of  cardboard.  Before  use  they  should  be  varnished  outside  with  shellac  dissolved  in 
alcohol  to  preserve  them  from  damp. 

Glass  topped  boxes. -—The  hmdij  shes  are  f  ^f  ^^  J   they  should  be  of  cardboard 

with  glass  top,  and  also  varnished  outside. 

Tubes.— Glass  tubes,  well  corked,  are  the  handiest  things  for  general  collecting. 
Two  sizes  are  useful,  3x1  inch,  and  2  X  f  inch. 

Killing  bottle — Is  best  made  with  a  well  stoppered,  wide-mouthed  bottle  as 
described  above. 

Knife. — A  good  knife  is  essential. 

Pins.—D.  F.  Tayler's  Nos.  3,  3,  7,  12,  16,  and  20,  meet  all  ordinary 
requirements. 


ZQ% 


APPENPIX   B.     COLLECTING,    PINNING,  SETTING. 


Store  boxes.— k  useful  size  is  17^X12X3^  ;  thin  sheets  of  corkf  inch  thick  are 
used  for  lining,  covered  with  white  paper.  There  should  bo  a  cell  in  one  corner  for 
naphthalene. 


Fig,  E. 

Kite  Net. 


Forceps— Are   useful  for  handling   fine  insects,  they  should   be  long  and  curved, 

with  fine  points.  Coarser  curved 
or  bent  forceps  are  useful  for 
handling  pinned  insects. 

Punch. — A  20-bore  gun-wad 
punch  is  useful  for  cutting  discs 
of  white  card  for  mounting  flies. 
Lens. — A  good  aplanatic 
magnifying  10  to  16  diameters  is 
essential  for  small  insects. 


Fig.  S. 

Forceps /or  handling  small  insecis ;  •ginning 

forceps  have  broader  xioints. 


Setting  boards.— Thete  may  be  obtained  in  the  flat  form  for  high  setting,  in  the 
flat  for  low  setting  or  in  the  oval  form  for  low  setting.  Flat  setting  boards  in  either 
form  are  preferable  to  oval.  '^ 

P?Y^,— Polyporus  pith  (imported)  is  a  very  good  material  for  staging  small 
insect?.    At  a  pinch  any  good  tough  pith  will  answer. 


INDEX,  AND  LISTS  OF  ILLUSTRATIONS, 
AND  PLANTS. 


INDKX. 


American  Bollworm,  144,  89. 
Anjoumois  Grain  Moth,  256. 
Ants,  injurious,  231. 

„       harvesting,  232. 

„       white,  228. 
Aphis,  239. 

„      cotton,  110. 

„      wheat,  124. 
Arecanut  Weevil,  253. 


B 

Bags,  72,  73,  186, 189,  223. 
Baits,  74, 192. 
Balance  of  Life,  65. 
Bamhoo  Beetles,  260. 
Baskets,  74. 
Batesian  Mimicry,  47. 
Beetle,  Bamboo,  260. 

„       Biscuit,  252. 

„      Blister,  205,  122,  138,  165. 

„      Cheroot,  253. 

„      Cockchafer,  196,  122. 

„       Epilachna,  204,  164. 

„       Flea,  203,  124. 

,,       Leaf -eating,  200. 

„       Palm,  207. 

„       Rhinoceros,  207. 

„       Sawtooth,  252. 

„       Surface,  220. 

„      Tortoise,  201. 

„      Wheat,  251. 
Beneficial  Insects,  268. 
Bherwa.  227. 
Birds,  67,  280. 


B — contd. 

Biscuit  Beetle,  252. 
Biting  Flies,  267. 
Black  Blight,  242. 

Black  Spotted  Grasshopper,  213,  113. 
Blister  Beetles,  205,  122,  138,  165. 
Brown,  205,  138. 
Green,  205,  138. 
„  „        Orange  banded,  205, 

165. 
Bollworm,  Pink,  93. 

„  American,  144: 

Spotted,  89. 
Bombay  Locust,  217. 
Borer,  Brinjal  Fruit,  166. 
„      Cane,  125. 
„      Cotton  Stem,  100. 
„       Orange,  178. 
,.      White,  130. 
Bot  Flies,  266. 
Broods,  30. 
Brown  Blister  Beetles,  205,  138. 

„      Bug,  244. 
Bud  Caterpillar,  Cotton,  99. 
Bug,  Betel  Vine,  234. 
„      Brown,  244. 
„      Coffee  Berry,  235. 
„      Dusky  Cotton,  107. 
„      Giant  Red,  235. 
„      Green,  168,235. 
„  „       of  coffee,  245. 

„      Mealy,  242. 
„      Painted.  233,  155. 
„     Plant,  233. 
„     Red  Cotton,  104. 
,,     Rice,  116. 
Butterfly,  life  history  of,  16. 


306 


INLEX. 


Carbolic,  84. 
Carbon  bisulpbide,  258. 
Cask  Weevil,  253. 
Caterpillar,  Anar,  179. 
„  Bhindi,  167. 

„  Brinjal,  165. 

„  Castor,  158. 

Cotton,  112. 
Ginger,  168. 
Gram,  144,  189. 
Hairy,  112,  113,  162, 193. 
Jute,  151. 
„  Leaf -eating,  181. 

„  Lemon,  174. 

„  Maize,  138. 

„  parts  of,  3. 

„  Pumpkin,  165. 

„  Sann  Hemp,  148. 

Sorghum,  138, 189. 
Surface,  190. 
„  Swarming,  187. 

Til  Leaf,  161. 
Tobacco,  156,  189. 
Turpod,  140. 
Tur  leaf,  143. 
Cattle  Bot,  266. 

„      Fasts  of,  261. 
Classification,  52. 
Clean  culture,  68. 
Climatic  checks,  63. 
Cockchafers,  196. 
Coleoptera,  definition  of,  53. 
Colour,  44. 
Contact  poisons,  76. 
Creosote,  84. 
Crickets,  224,  157. 
Crude  oil  emulsion,  82. 
Cryptic  colouring,  44. 
Cryptic  form,  37. 
Cutworm  (Surface  Caterpillar),  190. 


D 


Deceptive  colouring,  48. 
Diamond-back  Moth,  152. 
Dipping  seedlings,  223. 


D — contd. 

Diptera,  definition  of,  54. 
Diseases  of  Insects,  64,  65. 
Dusky  Cotton  Bug,  107. 


Eggs,  22-24. 

,,      form  of,  24. 

„       number  of,  23. 

„      period  of,  24. 

„      where  laid,  24. 
Epilachna  Beetle,  204, 


Females,  undeveloped,  29. 
Flea  Beetle,  Rice,  203. 
„       „         San,  203. 
„       „        Wheat,  203. 
Fleas,  261. 
Flies,  biting,  267. 
„     fruit,  170. 
„     Gad,  264. 
„     Horse,  265. 
„     parasitic,  270. 
Fly,  Cane,  134. 
„     Maize,  137. 

„     Melon  fruit,  164,  170,  171. 
„     Rice  Stem,  118. 
„     Tur  pod,  142. 
Food,  10. 

„     plants,  13. 
Form,  36. 
Fruit,  pests  of,  1 70. 

„      Borer,  Brinjal,  166,  168. 
„      flies,  170. 
Fumigation,  cotton  seed,  95. 
,  seed,  258. 


Q 

Gad  Flies,  264. 
Genus,  defined,  58. 
Giant  Red  Bug,  235. 


INDEX. 


307 


Q — contd. 

Gondal  fluid,  285. 
Grain  pests,  251. 

Grasshopper,  life  liistory  of,  18,  19. 
„  Kice,  119. 

Snouted,  213,  214. 
„  Painted,  212. 

Black  Spotted,  113,  213. 
„  Surface,  118,  220,  157. 

Gi-asshoppers,  210. 
Green  Blister  Beetle,  205. 
„      Bug,  168,  235. 
„         „     of  coffee,  244. 
„      Fly,  237. 
„      Mealy  Scale,  245. 
„      Weevil,  202. 


H 

Hairy  Caterpillars,  193,' 112. 
Hand-sprayer,  76. 
Hand-picking,  72,  147. 
Hand-net,  74. 
Harvesting  ants,  232. 
Hemiptera,  definition  of,  54. 
Hens,  71. 
Herbivores,  12. 
Hibernation,  30. 
Hispa,  Rice,  114. 
Hopper,  Cotton  Leaf,  109. 
Hoppers,  Mango,  173. 
Horse  Bot,  265. 

„      Flies,  266. 
Hymenoptera,  definition  of,  53. 


I 


Ichneumons,  268. 
Imago,  period  of,  28,  29. 
Insect,  parts  of,  3. 
Insecta,  definition  of,  1. 
Insecticides,  75. 
Internal  anatomy,  8. 


K 

Kerosene  emulsion,  81. 


Lace-wing  Flies,  275. 
Ladybird  Beetles,  273. 
Lamp  traps,  74,  199. 
Larva,  moults  of,  25. 
„       period  of,  25. 
Lead  arseniate,  79. 
Leaf  Beetle,  Red,  113,  164. 
„     Caterpillar,  Maize,  138. 
„  „  Tur,  143. 

Leaf -eating  Beetles,  200. 
Leaf-hopper,  Cotton,  109. 
Leaf -miner.  Groundnut,  148. 
Leaf -roller.  Cotton,  96. 
Leather  Beetle,  252. 
Lepidoptera,  definition  of,  54. 
Leptispa,  Rice,  201. 
Lice,  264. 
Life  history,  15. 
Light  traps,  74,  199. 
Locusts,  214. 

„         Bombay,  217. 

Piy,  219. 

Migratory,  214. 
„        Mite,  219. 

North- West,  215. 


M 

Maggot,  Ginger,  168. 
McDougal's  insecticide,  85. 
Mealy  Bugs,  242. 

„      Bug,  Cane,  245. 

„  „      Cotton,  113. 

„       Scale,  Green,  245. 
Wings,  240. 

„  „      Cane,  135. 

„  „       Orange,  177- 

Migratory  Locust,  214. 
Mimicry,  BatesHn,  47. 
„         Mui^   ian,  48. 


x2 


308 


INDEX. 


M — contd. 

Mixed  crops,  69. 
Mole  Cricket,  226. 
Motli  ■'borer,  125. 
Moth,  Diamond  Back,  152. 

„      Fruit,  177. 
Mouth-parts,  5. 
Mullerian  Mimicry,  48. 


N 

Nets,  74. 

Neuroptera,  definition  of,  53. 
Nomenclature  discussed,  57. 
North- West  Locust,  215. 


O 


Orange  banded  Blister  Beetle,  205. 
Origin  of  pests,  63. 
Orthoptera,  definition  of,  52. 


Painted  Bug,  233. 

„       Grasshopper,  212. 
Parasites,  12. 
Persian  Tick,  262. 
Phenyl,  84. 
Pink  Bollworm,  93. 
Plant  Bugs,  233. 
„      Lice,  237. 
Plume  Moth,  Tur,  140. 
Pod  Caterpillar,  Tur,  140. 
„    Fly,  Tur,  142. 
Predators,  12,  268,  269. 
biting,  273. 
„         stinging,  271. 
Preventive  measures,  68. 
Protective  devices,  38,  39. 
Pulse  Beetles,  254. 
Pupa.,  period  of,  28. 
„      where  found,  28, 


R 

Red  Cotton  Bug,  104. 

,,     Grain  Beetle,  253. 

„     Leaf  Beetle,  201. 

„    Spotted  Scale,  242. 

„     Weevil,  208. 
Remedial  measures,  71. 
Rhinoceros  Beetle,  207. 
Rice  Bug,  116'. 

„  Weevil,  251. 
Rosin  washes,  83. 
Rotation  of  crops,  69. 


Sanitary  fluid,  84. 
Saw-fly,  Mustard,  152. 
Saw-tooth  Beetle,  252 
Scale  Insects,  242. 
Scavengers,  12. 
Screw  Worm,  267- 
Semilooper,  Cotton,  112. 

„  Cabbage,  154. 

Senses,  8. 

Seven-spotted  Ladybird,  273. 
Sex  as  modifying  form,  39. 
Sheep  Bot,  266. 
Six-spotted  Ladybird,  273. 
Six-spotted  Tiger  Beetle,  118. 
Size,  34. 
Smoke,  74. 

Snouted  Grasshopper,  213,  214. 
Sounds,  42. 
Species,  defined,  57. 
Sphinx,  Til,  159. 
Spotted  Bollworm,  89. 
Spraying,  75. 
Spraying  machines,  77. 
Stem-borer,  Cotton,  100. 

„       „       Brinjal,  166. 

„      „      Tobacco,  156. 

„       ,,       Wheat,  122. 

„       Ply,  Rice,  118. 

„      Weevil,  Cotton,  103. 

,,  „         Jnte,  151. 

Stomach  poisons,  84. 
Success  Knapsack  Sprayer,  78. 


INDEX. 


309 


Surface  Beetles,  220. 

„       Caterpillars,  190. 

„      Grasshoppers,  220,  113,  151 

„      Weevils,  221. 
Syrphus  Flies,  277. 


Tamarind  Beetle,  256. 

Termites,  228. 

Ticks,  262. 

Tiger-beetle,  Six-spotted,  118, 

Timber  Beetles,  259. 

Tobacco,  insecticide,  84. 

Tortoise  Beetle.  201. 

Trap  crop,  70. 

Trenching,  71. 


w 

Warble,  266. 
Warning  colouration,  47. 
Weevil,  Arecanut,  253. 
Cask,  253. 

Cotton  Stem,  103,  104. 
,,        Green,  112. 

Jute,  151. 
„        Mango,  174. 
Palm,  208. 
Red,  208. 
„        Surface,  221. 
,,         Sweet  Potato,  163. 
White,  111,  112. 
Wheat  Beetle,  251. 
Wliite  Ants,  228. 
„      Borer,  130. 
„      Weevil,  111,  112. 


LIST   OK   ILLUSTRATIONS. 


w. 


1.  Millipede, 

2.  Tetranychus   hioculatus. 

M. 

3.  Ereunetis  semifiivora.    Wlsm. 

4.  Gibhium  scotias.     F. 

5.  Ereunetis  seminivora.    Wlsm. 

6.  Caterpillar  diagram. 

7.  Eumenes  petiolata.     F. 

8.  Dipteron. 

9.  Cossus  Ugniperda.     F. 

10.  Lucanus  hicolor.  Ho. 
Anthia  sexguttata.  F. 
Priotyrannus  mordax.    Wh. 

11.  ScJdzodactylus    monstruosus. 

Don. ;  mouthparts. 

12.  Beetle,  mouthparts. 

13.  Fly 

14.  Butterfly      „ 

15.  Moth 

16.  Halohates  frauenfeldus. 

Buch. 

17.  Oscinis  theae.     Big. 

18.  Danais  chrysippus.     Linn. 
19-24.  Danais  limniace,    Cr. 
25-29.  Acridium  succinctum.    L. 

30.  Seterogamia  indica.     Wlk. 

31.  Periplaneta  americana.     L. 

32.  Mantis  egg  case  and  young. 

33.  Eggs  of  Plant  Bug. 

34.  Cicada.     (G.  12S7.) 

35.  Laslocampid. 

36.  Larinus  eremita.     des  Log. 

37.  Odoiporus  longicollis.   Chevr. 

38.  Butterfly  chrysalis. 

39.  Thosea  cotesi.     Swinh. 

40.  Ilutilla  regia.     Sm. 

41 .  3Iak asen  a  graminivora . 

Hampsn. 

42.  Carteria  decorella.     Mask. 


43.  Deilephila  nerii.     Linn. 

44.  Zeuzera  coffeae.     Nietn. 

45.  Leucophaea        surinamensis. 

F. 

46.  Cimex  lectularius.     Linn. 

47.  Tarucus  theophrastus.     F. 

48.  Holochlora  albida. 

49.  Pliyllium  scythe.     Gray. 

50.  Limacodid. 

51.  Oecophylla  smaragdina. 

Fabr. 

52.  Mecopoda  elongata.     Linn. 

53.  Trachylepidiafructicassiella 

Rag. 
54-55.  Dorylus  lahiatus.     Schuck. 
56-57.  Luca7ius  lunifer.     Ho. 
58-59.  Hypolimnas  misippus.     L. 

60.  CuHcid. 

61.  Anisoneura  hypocyanea. 

Guen. 

62.  Chrotogonus.     Sp. 
63-64.  P seudospliinx  tetrio.     L. 

65.  Mylabris  pustulata.     F. 

66.  Eumenes  quadrispinosa. 

Sanss. 

67.  Ceria  eumenioides.     Sauiid. 

68.  EristaUs     arvorum.      Fabr. 

and  Apis  indica.     Fabr. 

69.  Teratodus  monticollis.     Dr. 

70.  Junonia  lemonias.     Linn. 

71.  Bredenbachius  pictus.     Dist. 
Monanthia  globuiifera.    Wlk. 

72.  Efacvomia  dorsalis.    Thunb. 

73.  Clirysofa  sp. 

74.  ApheUnus  theae.    Cam. 

75.  Apis  dorsata.     Fabr. 

76.  Brachyaspistes  tibialis. 

77.  Chrysomelid. 

78.  Nonagria  uniformis.    Ddgn. 


312 


LIST  OP   ILLUSTRATIONS. 


79. 

DIpteron. 

170-171. 

80. 

Momaeocerus  variabilis.  Dall. 

172-174. 

81. 

Podontia  14-punctata.    Linn. 

175 

82. 

Hymenopteron. 

83. 

Dipteron. 

176-177. 

84. 

TJiosea  cervina.     Mo. 

178-179. 

85. 

Phyllium  scythe.     Gray. 

180. 

86. 

Xylehorusfornicatus.  Erichs. 

181-182. 

87. 

Coelosterna  sp. 

183-184. 

88. 

J, 

185-186. 

89. 

Pyralid. 

187. 

90,  91  & 

188-189. 

92. 

Bags. 

190. 

93-94 

Hand  Sprayer. 

191-192 

95-97. 

Success  Knapsack  Sprayer. 

193. 

98-103. 

Eariasfabia.     Stoll. 

194. 

104-106. 

Gelechia  gossypiella.   Saund. 

195-197. 

107. 

Urogaster  depressarice.  Ashm. 

198. 

108. 

Leaf     attacked     by     Sylepta 

199-206. 

derogata.     F. 

207. 

109. 

Sylepta  derogata.     P. 

208. 

110-113. 

Phycita  infusella.     Meyr. 

209-210. 

114-119. 

Sphenoptera  gossypii.    Kerr. 

211. 

120-321. 

Cotton-stem  Weevil. 

212. 

122. 

Lygaeus  hospes.     Tabr. 

213. 

123. 

Dysdercus  cingulatus.    Fabr. 

214. 

124. 

Graptostethus  servus.  Fabr. 

215. 

125. 

Dysdercus  cingulatus.  Fabr. 

216. 

126. 

Oxycaraenus  laetus.     Kby. 

217-219. 

127. 

Jassid. 

220-221. 

128-130. 

Aphis  gossypii.     Gl. 

222. 

131. 

Hispa  aencscens.     Baly. 

223. 

132-133. 

Leptocorisa  varicornis.  Fabr. 

224. 

134. 

Cicindela  seocpunctata.     L. 

225. 

135-138. 

Heiroglyphus  furcifer.     Seiv. 

226. 

139. 

Melanitis  ismene.     Cr. 

140-142. 

Nonagria  uniformis.     Ddgn. 

227-229. 

143-150. 

Chilo  simplex.     Butl. 

230. 

151. 

JBlepharipoda  sp. 

231-232. 

152. 

Scirpophaga  auriflua.    Zell. 

153. 

Dietyophara  pallida.     Don. 

233. 

154. 

Aleurodes  barodensis.     Mask. 

234. 

155. 

Delphax  psylloides.     Leth. 

235. 

156. 

Cirphis  unipuncta.     Haw. 

236. 

157-160. 

PJjcelasta  2>arasita.     Meyr. 

161-164. 

Chloridea  obsoleta.     F. 

237. 

165. 

Amsacta  moorei.     Butl. 

238. 

166-168. 

Utetheisa  pulchella.     L. 

239. 

169. 

3Iaruca  testulalis.     Gey. 

240. 

.  Plutella  maculipennis.    Curt. 
.  Plusia  signata.     F. 
.  Rhopalosiphuin  dianthi. 

Schr. 

Prodenia  Uttoralis.    Boisd. 

Ophiusa  meliceHe.     Dr. 
.  Ergolis  inerione.     Cr. 

Acherontia  styx.     Westw. 
.  Diacrisia  obliqua.     Wlk. 

Cylas  turcipennis.     Botm. 
'  Glyphodes  indica.     Saund. 

Leucinodes  orhonalis.     Guen. 
.  Nezara  viridula.     L. 
.  Daeus ferrugineus.     01. 
.  Rivellia  persicae.    Big. 

Carpomyia  parctalina.    Big. 

Papilio  demoleus.     L. 
,  Stromatium  barbatum.    Fabr. 
,   Virachola  isocrates,     Fabr. 
,  Pyrausta  machceralis.    Wlk, 

Lasiocampid. 
,  Zinchenia fascialis.     Cram. 

Cirphis  loreyi.     Dup. 

Polytela  gloriosce.     Fabr. 

Noctuid. 

Caradrina  exigua.   Hiibn. 
.  Euxoa  segetis-  Scliiff. 

Agrotis  flammatra.  Schiff. 

Diacrisia  obliqua.     Wlk. 

Amsacta  albistriga.     Wlk. 

Amsacta  lactinea.  Cram. 

Argina  cribraria.  Clerck. 

Utetheisa  pulchella.  L. 

Melolontbid. 

Lachnosterna  impressa. 

Burm. 

Melolontbid. 

Serica  assamensis.  Brenske. 

Adoretus  hangalorensis. 
Brenske. 

Aulacophora  Jovcicollis.  Kiist. 

Aulacophora  excavata.    Baly. 

Leptispa  pygmaea.  Baly. 

Aspidiomorpha  miliaris. 

Fabr. 

3Iyllocerus  maculosus.   Desb. 

Astycus  lateralis,  Fabr. 

Chaetocnema  basalis,  Baly. 

Epilachna  2S-punctata,  Fabr. 


LIST    OF    ILLUSTRATIONS. 


S18 


241-242. 

Mylahris  pustulata.  Fabr. 

287-288. 

243. 

Cantharis  tenuicolUs.  Pali. 

289. 

244-245. 

Cantharis  rouxi.  Cast. 

29U. 

246. 

Oryctes  rhinoceros.  Linn. 

291-292. 

247. 

BhyncJiophorus  signaticollis. 

293. 

Chevr. 

294. 

,      248. 

Tylotropidius             didymus. 

295. 

Thunb. 

296. 

249. 

Poecilocera  ficta.  Fabr. 

250-251. 

Acridium            aeyuginosum. 

297. 

Burm. 

298-301. 

252. 

Tryxalis  turrita.  Fabr. 

302. 

253. 

Acridium  peregrinum.  01. 

303. 

254. 

Acridium  succincfum.  Liiiii. 

304. 

255. 

Acridium  peregrinum.  01. 

305. 

256-258. 

Acridium  succinctum.  Linn. 

306. 

259. 

Miltogramma  duodecimfunc- 

307. 

tata.  Big. 

308. 

260. 

Anthomyia       pesliaicarensis. 

309. 

Big. 

310. 

261. 

Tanyinecus  indicus.  Des.  Log. 

311. 

262. 

Opatrum  depressum,  Fabr. 

312. 

263. 

Epacromia  dorsalis.  Thunb. 

313. 

264. 

Chrotogoiius  lugubris.  Blanch. 

314. 

265. 

Chrotogonus        trachyfterus. 

315. 

Blanch. 

316. 

266. 

Brachytrypes          achatinus. 

317. 

Scoll. 

318. 

267. 

Spheoc  lobatus.  Fabr. 

319. 

268. 

Gryllodes       melanocephalus. 

320. 

Sei-v. 

'             321. 

269. 

Liogryllus  himaculatus.  deG. 

322. 

270. 

Gryllotalpa  africana.  Pal.  B. 

323. 

271. 

Schizodactylus    monstruosus. 

324-325. 

Dor.. 

326. 

272-275. 

Termes  taprobanus.  Hag. 

327. 

276 

Dorylus  orientalis.  Westw. 

328. 

277 

Agonoscelis  nubila.  Fabr. 

329. 

278 

Bagrada  picta.  Fabr. 

330. 

279 

Mouthparts  of  Hemiptera. 

280 

Disphinctus  humeralis.  Wlk. 

331. 

281 

Loldta  grandis.  Gr. 

282 

Calocoi'is  angustatus.  Leth. 

I      332-337. 

283 

Calocoris  Uneolatus.  Goeze. 

338-842. 

284 

Blissus  gibbus.  Fabr. 

343. 

286 

Aphanus  sordidus.  Fabr. 

344. 

286 

Apliis  malvae.  Pass. 

)      345-346. 

Alenrodid. 

Aleurodes  nubilans.  Buckt. 
Aspidiotns  ficus.  Ashm. 
Lecanium  nigrum.  Nietn. 
Aspidiotus  Jlcus.  Ashm. 
Chionaspis  separata.  Gr. 
Eriochiton  theae.  Gr. 
Chionaspis     prunicola     var. 

theae.  Mask. 
Dactylopius  citri.  R. 
Calandra  oryzae.  Linn. 
Trogosita  mauritanica.  Linn. 
Laemophlaeus  pusillus.  Fabr. 
Silvanwi  surinamensis .  Linn. 
Lasioderma  testaceum.  Duft. 
Anthrenus  sp. 

TriboUumferrugineum.  Fabr. 
Work  of  Bruchid. 
Caryoborus  gonagra.  Fabr. 
Bruchus  emarginatus.  All. 
Bruchus  chinensis.  Linn. 
Ephestia  cahiritella.  Oliv. 
Bostrichus  aequalis.  Waterh. 
Dinoderus  distinctus.  Le. 
Araecerus  fasciculatus,  deG. 
Argas  persicus.  Fabr. 
Pediculus  capitis. 
Chrysops  dispar.  Fabr. 
Tabanid  larva. 
Sippobosca.  sp. 
Pimpla  punctator.  Linn. 
Cotesiaflavipes.  Cam. 
Ichneumon. 
Tachinid. 

Platygaster  oryzce.  Cam. 
Eumenes  esuriens.  Fabr. 
Ammophila  laevigata.  Sm. 
Coelophora  sauzeti.  Muls. 
Chilomenes         sexmaculata. 

Fabr. 
,  Coccinella      septempunctata. 

Linn. 
Chrysopa,  spp. 
Syrphus  aegyptius.  Wied. 
Calosoma  orientale.  Ho. 
,  Anthia  sexguttata.  Fabr. 
Mantid. 


LIST   OF   PLANTS. 


[Names  in  bold  type  are  those  used  in  the  text,  to  ivhich  alone  page  references 
are  given.  Names  in  italics  are  scientific,  names  in  Roman  are  vernacular  and 
English,  reference  being  given  in  every  case  to  the  equivalent  word  used  in  the 
text.     Figures  in  bolder  type  are  principal  references  to  the  pests  of  that  plant.'] 


Advak  (Ginger). 

Atim  (Opium). 

Akh,  171,  212,  231. 

Ale  (Ginger). 

Alu  (Potato). 

Am  (Mango). 

Amba  (Mango). 

Ambadi,  185. 

Anar,  179. 

Andropogon  sorghum  (Sorghum). 

Arachis  hypogcea  (Groundnut). 

Areca  catechu  (Betel  Nut  Palra). 

Areca  Nut  Palm  (Betel  Nut  Palm). 

Arend  (Castor). 

Arhar  (Tur). 

Artichoke,  232. 

Avena  sativa  (Oats). 


Baigan  (Brinjal). 
Bajra,  146, 198,  200,  206,  235. 
Banti  (Sama). 
Baril  ban  (Cotton). 
Barley,  222. 
Belati-mung  (Groundnut). 
Benincasa  cerifera  (Melon). 
Ber,  17(5. 

Betel  Nut  Palm,  215. 
Betel  Vine,  235. 
Bhang  (Ganja). 

Bbat  (Soy    bean  in   Bengal)  (Kice    in 
Bombay). 


B — contd. 

Bhindi,   90,  92,  98,  1U5,   108,  112, 
167. 

Bhoising  (Groundnut). 

Bhuimug-  (Groundnut). 

Bhuta  (Maize). 

Bijaura  (Lemon). 

Brahmokha  (Artichoke). 

Brassica     campestris      var.     Sarson 

(Mustard). 
Brassica  juncea  (Mustardj. 
Brassica      napus      var.     Dichotoma 

(Rape). 
Brassica  oleracea  (Cabbage). 
Brinjal,  165,  171,  203,  204. 
But  (Gram). 


Cabbage,  152,  232. 

Cajanus  indicus  (Tur). 

Calotropis,  spp.  (Akh). 

Cannabis  sativa  (Ganja). 

Capsicum,  spp.  (Chillies). 

Castor  Plant,  158,  159,  195,  241. 

Cauliflower,  152,  232. 

Chal  kamra  (Melon). 

Chana  (Gram). 

Chawal  (llice). 

Chena  (Small  millets). 

Chick  pea  (Gram). 

Chillies,  229. 

Cholam  (Sorghum). 

Cicer  arietinum  (Gram). 


316 


LIST   OP   PLANTS. 


C — contd. 

Citrullus  vulgaris   (Melon). 

Citrus  aurantium  (Orange\ 

Citrus  medica  (Lime). 

Cocoanut  Palm,  20". 

Cocos  micifera  (Cocoanut  palm). 

Coffea  arahica  (Coffee). 

Coffee,  235,  2M. 

Colza,  Indian  (Mustard). 

Corchorus,  spp.  (Jute). 

Corn  (Maize). 

Cotton,  89, 195,  205,  212,  222,  245. 

Crotalari a  juncea  (Sann  Hemp). 

Cucumber,  164,  201, 205. 

Cucumis,  spp.  (Melon). 

Cucurbita,  spp.  (Pumpkin). 


D 

Darim  (Anar). 
Dhan  (Eice). 
Diveli  (Castor). 
Doliclios  lahlah  (Val). 
Dudhi,  204  (see  Gourd). 


Eggplant  (Brinjal). 

Erandi  (Castor). 

Euphorhia  ner-iifolia,  75,  209. 


G 

Ganja,  146. 
Ganna  (Sugarcane). 
Gehun  ^Wheat). 
Ghau  (Wheat). 
Gingelly  (Til). 
Ginger,  168. 

Glycine  hispida  (Soy  Bean). 
Gobhi  (Cabbage). 
Grossypium,  spp.  (Cotton). 
Gourd,  164,  171,  201. 
Gram,  145,  191,  222. 
Great  Millet  (Sorghum). 


Q — eontd. 

Groundnut,  147,  195,  229. 

Guava,  180. 

Gur  began  (Tomato). 


H 


Selianthus  annuus  (Sunflower). 
Selianthus  tuherosus  (Artichoke). 
Hemp,  Indian  (Ganja). 
„         Roselle  (Ambadi). 
Hibiscus  cannabinus   (Ambadi). 
Hibiscus  esculentus  (Bhindi). 
Hibiscus,  Garden,  106,  205. 
Holly  hock,  98. 


I 


Ikh  (Sugarcane). 
Indian  Colza  (Rape). 
Indian  Hemp  (Ganja). 

,,      Bean  (Val). 
Indigo,  146,  150,  202, 203,  239. 
Indigofera  (Indigo). 
IfomcBa  batatas  (Sweet  Potato). 
Italian  Millet  (Kangni). 


Jai  (Oats). 
Jinjeli  (Til). 
Jowari  (Sorghum) 
Juar  (Sorghum). 
Jute,  151,  195. 


K 

Kaddu  (Dudhi). 
Kakun  (Kangni). 
Kambu  (Bajra). 
Kamila-nimbu  (Orange). 
Kangni,  232. 
Kapas  (Cotton). 


LIST    OF    PLANTS. 


317 


K-—contd. 


Karbuz  (Melon). 
Karela  (Goard). 
Ivarva  nimbu  (Lemon) 
Khajur  (Toddy  Palm). 
Kumra  (Melon). 
Kutki,  206. 


Lady's  Finger  (Bhindi). 

Lagenaria  vulgaris  (Dudbi,  Gourd). 

Labi  (Rape). 

Lalgacbh  (cbillies). 

Lai  mircb  (cbillies). 

Lemon,  174. 

Lime,  174. 

Lab-lab  Bean  (Val). 

Loquat,  180. 

Lucerne,  146,  191. 

Luffa  acutangula  (Turia). 

Lycopersicum  esculentum  (Tomato). 


M 


Maize,    112,  113,  125, 146,  222,  235, 
239. 

Makai  (Maize). 
Mangifera  indica  (Mango). 
Mango.  170,  22?,  231,  241. 
Matar  (Pea). 
Mat-kalai  (Groundnut). 
Medicago  sativa  (Lucerne). 
Melon,  164, 171,  201. 
Millet,  Great  (Sorgbum). 
„        Bulrusb  (Bajra). 

Small,  117, 198,  200,  222, 235. 
Mirchi  (Cbillies). 
Mitba  kaddu  (Melon). 
Mitba  alu  (Sweet  Potato). 
Momordica  charantia  (Gourd). 
Mung  pballi  (Groundnut), 
Mula  (Radisb). 
Mulberry,  245. 
Mung,  149. 
Mustard,  152,  203,  235,  239. 


N 

Narango  (Orange). 
Nariyal  (Cocoanut  Palm). 
Nicotiana,  spp.  (Tobacco). 
Nil  (Indigo). 
Nimbu  (Lime). 


O 

Oats,  222. 

Ocbro  (Bbindi). 
Opium,  145, 146, 191,  222. 
Orange,  174,  241. 
Oryza  sativa  (Rice). 


Palmyra,  207. 

Palms,  207. 

Pan  (Betel  vine). 

Panicum,  spp.  (Small  millets). 

„       frumentaceum  (Sama). 

„         miliare  (Kutki). 
Papaver  somniferum  (Opium). 
Pat  (Jute). 
Patsan  (Ambadi). 
Peach,  170. 
Pea,  191. 
Pea,  Pigeon  (Tur). 
Pennisetum  typhoideum  (Bajra). 
Phaseolus  radiatus  (Mung). 
Phcenix  sylvestris  (Toddy  Palm). 
Physalis  peruviana  (Tipari). 
Pbunt  (Melon). 
Pigeon  Pea  (Tur). 
Piper  betel  (Betel  vine). 
Pisum  spp.  (Pea). 
Pitwa  (Ambadi). 
Pomegranate  (Anar). 
Popat  (Val). 
Poppy  (Opium). 
Posta  (Opium). 
Potato,  168,  246. 
Punica  granatum  (Anar). 
Prunus  fersiccB  (Peacb). 
Psidium  guava   (Guava). 
Pumpkin,  164,  205. 


318 


LIST    OF    PLANTS. 


Radish,  152. 

Rahar  (Tur). 

Rai  (Mustard). 

Ram  kurthi  (Soy  bean). 

Bam  turai  (Bhindi). 

Rape,  Indian,  152,  235,  239. 

RapJianus  sativus  (Radish). 

Ratal  a  (Sweet  Potato). 

Rice,  114,  123,  203,  206. 

Ricinus  communis  (Castor). 

Roselle  Hemp  (Auibadi). 


Saccharum  officinarum  (Sugarcane). 

Safed-kaddu  (Pumpkin). 

Safra  kumra  (Melon). 

Sama,  117,  119. 

Sanai  (Sann  Hemp). 

Sann  Hemp,  148,  195,  203. 

Sanwa  (Sama). 

Sarson  (Mustard). 

Sawan  (Sama). 

Sem  (Val). 

Sesamum  indicum  (Til). 

Setaria  italica  (Kangni). 

Shakkarkand  alu  (Sweet  Potato). 

Shama  (Kutki). 

Sherdi  (Sugarcane). 

Sheria  (Ambadi). 

Shim  (Val;. 

Siddi  (Ganja). 

Sita  phal  (Melon). 

Solanum  onelongena  (Brinjal). 

Solatium  tuberosum  (Potato). 

Sorghum,  123,  125,  206,  222,  226, 

235,  239. 
Soy  Bean,  150. 
Sugarcane,  120,  123,  125,  222,  229, 

241. 
Sunflower,  146. 
Supari  (Betel  Nut  Palm). 
Suraj  mnkhi  (Sunflower), 
Surthi  (Tobacco). 
Sweet  Potato,  163,  202. 


Tag  (Sann  Hemp). 

Tamakhu  (Tobacco). 

Tambuli  (Betel  vine). 

Tarbuza  (Melon). 

Til,  159,  195. 

Tipari,  185. 

Tobacco,  145,156,191,  195,222, 

227. 
Toddy  Palm,  207. 
Tomato,  146. 
Torai  (Rape). 

Triticum  sativum  (Wheat). 
Tur,  140,  144,  239. 
Turia,  171,204. 
Tuver  (Tur). 


U 


Uri  (Rice). 

Us  (Sugarcane). 

Ukh  (Sugarcane) 


Val,  140,  161. 
Vari  (Kutki). 
Vengan  (Brinjal). 
Vilayati  baigan  (Tomato). 


W 


Wheat,  114, 122,  203,  222,  229,  239. 


Yellu  (Til). 


Zea  Mays  (Maize). 
Zingiber  Officinare  (Ginger), 


G.  I.  C.  P.  0,— No.  2Bnto.— 16.10-1906,— 2,550.— J.  J.  M. 


M>