Dec.  I,  1896.]  THE  TROPICAL  AGRICULTURIST. 
377 
THE  “LADYBIRD”  ENEMY  OF 
COFFEE-BUG— ADVERSE 
CRITICISM. 
NV'e  are  very  mucli  indebted  to  Mr.  E.  E 
Green —specially  qualified  as  lie  is  to  write  with 
authority  on  the  subject  for  the  following  com- 
munication sent  by  him  to  our  “ senior  ” in 
England.  It  will  be  seen  that  Mr.  Green  sees 
no  reason  in  the  adverse  criticism  recently 
ottered,  for  refusing  to  make  the  e.xperiment 
proposed  of  infesting  “ ladybird  ” beetles  to 
deal  with  the  green-bug  on  coffee  ; but  as  the 
expense  would  lie  widely  distributed,  our 
planters  in  Mysore,  the  Straits,  &c.,  if  they 
agreed  to  join  in  the  employment  of  Mr. 
Ktebele,  it  ought  not  to  ^eost  any  individual 
proprietor  more  than  a few  rupees.  We  are 
back,  therefore,  at  the  point  where  support  for 
a joint  mission  should  be  canvassed  for— who 
will  lead  the  way  ? Mr.  Green  writes  as  fol- 
lows : — 
“Budleigh  Salterton,  Devon,  Oct.  8.— I have  just 
been  reading  in  the  Ccj/lon  Observer  (Overland 
edition.  Sept.  16)  an  article  called  ‘ The  Lady- 
bird a Humbug,’  by  an  anonymous  correspondent 
“ There  are  one  or  two  points  in  the  articls 
that  warrant  a little  criticism.  Your  corres- 
pondent argues  from  the  fact  that  because  ‘scale- 
bugs’  abound  in  Australia,  therefore,  the  intro- 
duction of  ladybird  beetles  from  that  country 
must  manifestly  be  useless.  This  fact  does  not 
affect  the  position  at  all.  In  their  own  country 
the  beetles  are  hampered  by  numerous  natural 
enemies  and  parasites  that  prevent  them  from 
increasing  sutliciently  to  get  the  upperhand  of 
the  more  prolific  bugs.  But  when  the  beetles  are 
removed  to  some  other  country,  having  left  their 
natural  enemies  behind,  they  are  in  a position  to 
increase  and  multiply  unchecked  as  long  as  a 
plentiful  supply  of  tlieii  food  is  forthcoming.  And 
this  food  being  the  scale- bug,  the  failure  of  foed 
would  mean  the  success  of  the  ladybird  experi- 
ment. 
“ It  may  be  said  that  other  natural  enemies 
will  find  them  out  in  the  new'  country.  And  so 
they  will— in  time,  but  experience  shows  us  that 
it  is  usually  a long  time  before  fresh  enemies  ac- 
quire the  'habit  of  preying  upon  the  new  intro- 
duction. 
“ There  is  no  ([uestion  whatever  .'ibout  the 
value  of  the  work  effected  by  the  ‘ Vedalia  Lady- 
bird,’ which  w'as  imported  from  this  same  sc.ale- 
iufested  Australia.  In  a coniparatively  short  time 
this  insect  practically  freed  the  orange  planta- 
tions of  California  from  the  dreaded  ‘ flute-scale’ 
(Icei-i/a  purchasi)  that  had  proved  so  destructive 
there. 
“The  partial  failure  of  the  experiment  in  other 
places  requires  an  examination' of  the  particulars 
of  the  individual  cases  before  we  can  judge  of 
their  merits.  It  appears  -your  (j notations  supplied 
your  correspontlent — that  ladybiid  lieetles  ha\  e 
not  'dven  entire  satisfaction  when  employed 
aoaiiiiff  the  ravages  of  the  ‘black  scale’  {Leca- 
nmm  oleie).  Now  this  particular  bug  forms  a 
very  hard  scale  in  its  later  stages  which  serves 
as  a protection  for  the  large  number  of  eggs  de- 
47 
posited  beneath  it, — a fact  which  may  possibly 
account  for  its  ability  to  resist  the  attacks  of 
ihe  beetle. 
“ Our  own  chief  pest  the  ‘green  bug’  [Lecanium 
viride)  is  an  especially  unprotectecl  insect,  the 
skin  of  the  body  remaining  soft  to  the  end.  In 
this  particular  it  very  closely  resembles  the  species 
which  w'e  are  told  by  Mi'.  Koibele  has  been  ex- 
terminated in  Honolulu  through  the  agency  of 
ladybird  beetles — also  originally  hailing  from 
Australia. 
“Your  corre.spondent  very  justly  suggests  that 
‘ it  would  be  unwise  to  incur  any  extraordinary 
outlay  ’ in  the  matter.  I do  not  advocate  any 
extraordinary  or  even  very  heavy  expenditure. 
A few'  cents  per  acre  for  all  t.ie  cott’ee  in  the 
island  w'ould  produce  sufficient  funds  for  the  start- 
ing of  the  experiment.  The  suggested  remedy  is 
not  of  course  a certainty, — otherwise  there  w'ould 
be  no  two  questions  about  its  immediate  adop- 
tion. But  if  nothing  should  ever  be  attempted 
for  fear  of  possible  failure  there  would  not  be 
much  progress  in  the  world  ! The  possible  bene- 
fit is  enormous, — far  out-balancing  the  expense 
of  a ])ossible  failure. 
“I  notice  that  one  of  the  critics  ([uoted  by 
your  correspondent  impugns  the  value  of  the 
ladybird,  partly  because  ‘she  does  not  extirpate 
the  fungus.’  Surely  this  is  rather  unreasonable  ! 
f presume  the  fungus  in  question  to  be  the  sooty 
growth  usually  associated  with  an  attack  of 
‘ bug.’  But  if  you  kill  the  cause  (the  bug),  the 
effect  (the  fungus)  w'ill  soon  pass  off.  Moreover 
this  fungus  is  not  in  itself  injurious  to  the  plant. 
It  germinates  and  subsists  solely  upon  excre- 
mentitious  matter  from  the  bugs. 
“ As  for  your  correspondent’s  concluding  re- 
marks upon  scientific  as  opposed  to  practical  work. 
In  many  cases  the  life  history  of  an  organism 
must  first  be  known  before  a logical  remedy  can 
be  suggested.  It  is  possible  that  a scientist — 
from  liis  special  training — may  be  in  a better 
position  to  carry  out  the  fir.st  part  of  the  w'ork  ; 
while  the  practical  agriculturist  may  best  know 
how  to  apply  the  results  of  the  first  man’s 
labours.” 
To  w'hich  we  may  add  rdiat  there  is  surely  a 
high  negative  value  to  be  attached  to  the  scien- 
tist’s work  when  he  is  able  to  indicate — as 
Thw'aites  originally  did  and  Marshall  Ward 
later— the  fruitlessness  of  the  coffee  planter  try- 
ing to  expel  the  leaf  fungus  from  his  fields 
when  once  it  has  taken  possession.  Now,  the 
fungus  is  supposed  to  be  in  a decaying  state 
itself  in  Ceylon,  while  the  “green-bug”  has 
long  been  regarded  as  a far  more  serious  enemy  ; 
and  science  as  w'ell  as  practice  points  to  a 
remedy  in  the  “ Vedalia  ladybird  ” to  be  got 
from  Queensland. 
«- 
FRUIT  CULTURE  ON  THE  INDIAN 
HILLS. 
Some  interesting  facts  regarding  fruit  culture  in 
the  hills  are  given  by  the  Rev.  M.  M.  Carleton  in 
the  last  issue  of  the  Notional  Mcajazine,  published 
in  Calcutta.  Mr.  Carleton,  who  is  one  of  the  fore- 
most pioneers  of  the  fruit  growing  industry  in  the 
Himalay.as,  has  made  various  experiments  at  Ani, 
a village  in  Knlu,  4,500  feet  above  sea-level  and 
