THE  TROPICAL  AGRICULTURIST. 
[Fee.  I,  1897. 
selves  by  suction,  and  are  considered  to  pass  from 
eight  to  ten  months  in  maggot  state,  attached  b 
their  mouth  hooks  to  the  lining  membrane  of 
portion  of  the  stomach. 
Sometimes  there  may  be  only  a few  of  these  mag- 
gots present  ; sometimes  (as  I have  seen  myself)  they 
are  present  in  such  numbers  as  to  lie  close  up  against 
each  other  over  a large  patch  of  surface,  so  that  it 
hardly  seemed  possible  to  find  room  for  another 
amongst  them.  Hero  they  live  until,  when  full-fed, 
they  loose  their  hold ; and  after  being  thrown  to 
the  ground,  tuin  to  a brown  pupa,  from  which  the 
fly  comes  out  in  a few  weeks. 
For  prevention  of  this  attack,  such  treatment  as 
combing,  brushing,  or  clipping  hair,  so  as  to  get  rid 
of  the  eggs,  is  sure  to  be  of  use.  Also  the  applica- 
tion of  soaps,  or  washes,  with  scents  deterrent  to  in- 
sect attack  ; and,  likewise,  freedom  to  the  horses  to 
shelter  in  sheds  in  the  heat  of  the  day.  Hemedies 
fall  within  the  province  of  the  veterinary  adviser,  as 
special  advice  is  needed  for  their  safe  application. 
The  Ox  Warble  Fly,  or  Hot  Ply,  is  a two-winged  fiy, 
upwards  of  half-an-inch  in  lengtli,  so  b.anded  and 
marked  with  differently  coloured  hair  as  to  be  not 
unlike  a humble  bee.  The  face  is  yellowish,  the  body 
between  the  wings  yellowish  before  and  black  behind, 
and  the  abdomen  whitish  at  the  base,  black  in  the 
middle,  and  orange  at  the  tip.  The  female  is  fur- 
nished with  a somewhat  teiescopic-formed  extension 
of  the  end  of  the  abdomen,  which  acts  as  a long  egg- 
laying  tube,  and  the  egg  is  white  and  oval,  with  a sm  11 
brownish  lump  at  one  end. 
On  hatching  from  the  egg,  the  maggot  is  not  of 
the  thick,  oval  shape  to  which  it  afterwards  changes, 
but  is  almost  worm  like  in  shape,  and  is  furnished 
with  a pair  of  cutting  forks  at  the  mouth  end.  By 
careful  examinations  of  sections  of  hide  in  the  very 
earliest  stage  of  attack,  a fine  channel  or  perfora- 
tion will  be  found  leading  from  the  outside  of  the 
hide,  right  through  it,  down  to  the  under  side. 
Here  the  young  maggot  will  be  found,  and  by 
gentle  pressure,  the  course  of  the  maggot  channel 
may  be  clearly  traced  by  the  little  drop  ef  blood 
which  (in  my  own  observation)  I have  found  can 
readily  bo  forced  along  it  from  the  larvie  working 
below,  till  it  stands  as  a minute  drop  on  the  outside 
of  the  hide.  This  channel  I have  found  to  bo  rough 
and  jagged  ac  the  side,  thus  showing  it  was  gnawed 
or  torn  (uot  cleanly  pierced,  as  by  an  ovipositor), 
and  the  direction  was  very  various,  so  as  even  to 
be  much  cured. 
The  maggot  gradually  increase  in  size,  still  lying 
with  the  tail  end  uppermost,  or  nearest  the  opening 
in  the  hide  ; and  as  it  grows  it  presses  back  ancl 
opens  the  surrounding  tissue,  till  it  lies  with  the 
tail  extremity  in  the  opening  of  the  boil-like  swell- 
ing, commonly  known  as  the  “ warble.”  Here  it 
draws  in  air  through  what  look  like  two  small 
black  (-pots  in  the  tail,  but  which  ai-e  really  the 
spiracles,  or  masses  of  minute  breatliing  open- 
ing.s,  by  which  air  is  admitted  into  the  breathing- 
tubes  or  trachea  of  the  maggot.  It  feeds  by 
sucking  in  the  putrid  matter  flowing  into  the 
cavity  its  presence  has  caused,  and  there  it  remains 
until  it  is  full  grown,  that  is,  about  an  inch  long. 
This  may  be  at  any  time  from  May  to  much  later 
in  the  season,  and  then,  with  the  help  of  the  rows 
of  prickles  with  which  it  is  furnished  outride,  and 
the  powerful  net-work  of  muscles  with  w'hich  it  is 
furnished  within  the  skin,  it  drags  itseil  through 
the  opening  of  the  warble,  tail  foremost,  and  fails 
to  the  ground,  where  it  finds  some  shelter,  cither 
in  the  ground  or  under  a stone  or  clod,  where  it 
changes  to  a chrysalis.  The  chrysalis  is  dark-brown 
or  black,  much  like  the  maggot  in  shape,  only  flatter 
on  one  side ; and  from  this  brown  husk  the  warble 
fly  comes  out  in  three  or  four  weeks,  but  this  lein.jth 
of  time  is  ii. creased  by  cold  weather. 
Where  the  attack  is  severe,  the  eondition  of  the 
surface  of  the  carcase  baneath  known  as  “ licked 
beef,”  or  “ butcher’s  jelly,”  is  to  bo  found,  which 
is  a very  serious  drain  on  the  health,  condition. 
and  (iuality  of  the  animal,  thus  well  described  by 
Mr.  0.  E.  Pearson,  wholesale  butcher,  Sheffield  ; 
” I may  say  that  the  effect  of  warbles  on  the 
carcase  is  more  serious  than  can  possibly  be  imagined 
by  the  outside  appearance  of  the  beast 
The  carcase  of  beef  assumes  a nasty  yellow 
colour,  and  also  a soft,  flabby  appearance 
on  the  outside  rind  of  the  beast  (where  the  warble 
has  been  in  operation),  so  much  so  that  the  carcase 
has,  in  some  cases,  to  be  pared  down  to  the  flesh 
to  make  the  appearance  of  the  animal  at  all  pre- 
sentable for  the  rrrarket,  causing  thereby  a grievous 
amourrt  of  loss  to  the  butcher.  I am  speaking  from 
tactical  experience,  killing  on  an  average  twenty 
easts  or  move  a week.” 
On  applying  to  Mr.  Henry  Thompson,  M.rs.c.v.s., 
of  Aspatria,  Cumberland,  who  has  long  devoted  much 
attention  to  w'arble  attack,  for  an  exact  descriptiorr  of 
the  damage,  he  replied  : — What  causes  the  damaged 
nreat  or  beef  is  the  chronic  inflammation  set  up  by 
the  warbles  irr  the  skin,  which  extends  to  the  con- 
nective tissues,  thence  to  the  flesh,  producing  the 
straw  coloured,  jelly-like  appearance  of  a newly  slaugh- 
tered carcase  of  beef,  which,  in  twelve  or  twenty- 
four  hours,  when  exposed  to  the  air,  turns  a dirty 
greenish  yellow  colour,  and  thus  spoils  the  beef, 
having  a frothy  discharge  oozing  from  the  surface 
with  a soapy-like  look.” 
Its  prejudicial  nature  in  all  points  of  view  is  thus 
shortly  given,  in  the  last  words  of  some  obseiwa- 
tions  with  which  I was  favoured  by  Mr.  John  Peu- 
berthy.  Prof,  of  Pathology  at  the  Itoyal  Veter- 
inary’ College,  Camden  Town,  N.-W.,  regarding 
some  specimens  on  which  I had  requested  his 
opinion  : — “ The  material  is  uot  fit  for  human  con- 
sumption. I think  it  very  deleterious  to  the  health 
and  comfort  of  the  affected  animal.” 
The  yearly  loss  from  this  attack  of  is  enormous. 
Firstly,  there  is  the  loss  on  milk,  and  on  many 
other  points  of  damage  consequent  on  the  wild 
gallop  of  the  cattle  when  terrified  by  the  fly. 
Secondly,  there  is  the  loss  on  the  condition  of  the 
infested  animal.  Every  warbled  hide  is  a sign  of  so 
much  out  of  the  farmer’s  pocket,  for  the  food  he 
spent  in  feeding  grubs  in  his  cattle’s  backs  which 
should  have  gone  to  form  meat  and  milk,  instead 
of  being  wasted  in  foul  maggot-sores.  Thirdly, 
there  is  the  loss,  falling  mainly  on  the  butchers, 
consequent  on  damage  to  surface  of  carcase  known 
as  ‘‘licked  beef”  or  butcher’s  jelly.”  Fourthly, 
there  is  a great  loss  on  the  injured  hides.  The 
two  following  returns,  from  Newcastle-on-Tyne  and 
Aberdeen  respectively,  taken  from  a number  of  re- 
turns from  hide  or  cattle  companies,  etc.,  with 
which  I was  favoured  in  1888,  give  some  slight  idea 
of  the  loss  going  on,  simply  on  this  one  item  of 
pe  fectly  needless  waste.  The  following  is  from  New 
carstle-on-Tyne : — 
“ In  a period  of  twelve  mouths,  102,877  hides 
passc'd  through  the  market;  of  these,  00,000  were 
warbled.  Loss  esliniated  at  £15,000.” — J.  McG. 
‘‘In  five  months,  from  February  .Ird  to  June  24th, 
01,103  hides  passed,  of  which  11,0.30  were  warbled. 
Loss,  T2,873.” — W.  M.  & Son,  Aberdeen. 
'The  above  loss,  in  all  its  details,  is  wholly  un- 
necessary. By  the  use  of  the  simple  measures 
mentioned  below,  we  have  now  found,  from  the 
experience  of  our  leading  farmers,  cattle  owners, 
and  veterinary  surgeons,  during  about  twelve  years 
(that  is,  since  attention  was  first  directed  to  the 
subject),  that  the  attack  may,  to  all  practical  purposes, 
be  stamped  out. 
Squeezing  out  the  maggots  is  a sure  method  of 
getting  rid  of  them,  but  they  may  be  destroyed 
easily  and  without  risk  by  dressing  the  warble  with 
a little  of  McDougall’s  smear  or  dip,  or  with  a little 
cart-grease  and  sulphur,  applied  well  on  the  opening 
of  the  warble.  Mercurial  ointment  answers,  it  care- 
fully u.:ed-that  is,  in  very  small  quantity,  and  only 
applied  once  as  a small  touch  on  the  wnrble;  but 
where  there  is  any  risk  of  careless  npp.ication  it 
should  not  be  used.  Any  thick,  greasy  matter,  that 
will  choke  the  breathing -pores  of  the  maggot,  or 
poison  it  by  running  down  into  the  cell  in  wffiich  it 
