experiment  sake,  and  found  that  after  fumigating  they  were  just 
as  fresh  as  before.’’ 
WORK  WITH  USEFUL  INSECTS. 
Three  lots  of  horn  fly  enemies  collected  in  Germany  were  re- 
ceived from  Mr.  Koebele  during  the  month  and  turned  over  to 
Mr.  Swezey  of  the  Planters’  Experiment  Station. 
Melon  Fly  Parasites. — To  Mr.  Swezey  were  turned  over  also 
the  fruit  fly  parasites  upon  arrival  from  Australia  on  June  24th. 
His  report  I beg  to  submit  herewith.  Although  written  in 
August  his  work  of  breeding  was  finished  in  July.  Briefly  sum- 
marized it  is  to  the  effect  that  neither  of  the  two  parasites  bred 
showed  inclination  to  oviposit  in  our  melon  fly  larvae  or  pupae. 
A few  fruit  flies  were  the  first  to  issue  and  were  allowed  to  die  in 
the  tubes  before  removal.  The  most  interesting  were  the  small, 
dark  flies  that  issued  in  comparatively  large  numbers,  1 1 5 in  all. 
This  is  apparently  the  species  in  which  the  West  Australian  ento- 
mologists repose  much  of  their  hopes,  probably  Tetrastichodes 
as  identified  by  Dr.  Perkins  from  specimens  left  by  Mr.  Com- 
pere last  year.  Although  given  every  possible  opportunity  they 
failed  either  to  mate  or  attack  our  melon  fly  maggots.  The  de- 
velopment of  melon  flies  instead  of  parasites  from  these  maggots 
conclusively  proved  this  failure. 
Seven  specimens  of  an  Ichneumon  fly  were  also  bred,  but,  says 
Mr.  Swezey,  “only  in  one  instance  were  there  healthy  specimens 
of  both  sexes  present  at  the  same  time.”  These  two  were  short 
lived  and  failed  to  either  mate  or  attack  our  melon  fly  maggots, 
this  having  also  been  substantiated  as  above.  Our  thanks  are 
nevertheless  due  Mr.  Compere  for  sending  the  insects  and  Mr. 
Swezey  for  the  great  pains  he  took  with  the  work  of  breeding. 
I should  recommend  to  the  Board  to  endeavor  and  secure  another 
colony  from  West  Australia.  In  any  event  not  to  let  up  on  the 
work  of  relieving  the  country  of  the  melon  fly  pest  until  it  is 
crowned  with  success. 
Disinfection  of  Abandoned  Cucumber  Field. — In  accordance 
with  instructions  from  the  Board  on  the  7th,  I took  some  of  the 
nursery  men  to  the  field  on  the  10th  and,  after  careful  raking  up 
of  the  field  and  pouring  oil  on  the  heap,  had  it  set  on  fire.  This 
cleared  that  field  of  myriads  of  the  pest  that  would  have  otherwise 
bred  out  and  scattered  to  all  the  corners  of  the  island.  Mr.  Geo. 
Fairchild,  who  I was  informed  is  one  of  the  owners  of  the  estate, 
was  advised  of  our  action. 
Rust  on  Brake  Fern  (Pteris  aquilina). — At  the  request  of  Mr. 
L.  von  Tempsky  I secured  for  him  identification  of  the  rust  at- 
tacking it.  He  first  observed  this  rust  in  form  of  white  dust 
rising  from  the  fern  from  under  his  horse’s  feet  when  he  drove 
through  it.  I am  informed  by  Mr.  Lewton-Brain,  our  honorary 
plant  pathologist,  that  “this  fern  rust  ( Uredo  polypodii ) is  quite 
