rib.  These  parasites  have  multiplied  rapidly,  but  Paranagrus  and 
Ootetrastichus  are  more  common,  because  Anagrus  parasitizes  the 
eggs  of  other  Fulgorids  besides  Perkinsiella. 
From  only  four  individuals  of  Paranagrus  arrived  alive  at  the 
end  of  January,  1904,  at  Honolulu,  a very  large  number  was  ob- 
tained for  delivery  one  year  later  on  many  plantations. 
According  to  observations  by  Dr.  Perkins  about  the  end  of  1906 
from  leaves  with  eggs  of  Perkinsiella  which  had  been  collected 
on  a plantation,  which  before  had  suffered  great  damage,  3,275 
parasites  and  250  larvae  of  Perkinsiella  were  obtained  in  the 
laboratory  which  means  that  86.3%  of  the  eggs  had  been  de- 
stroyed. 
Otto  H.  Swezey  in  a report  of  a visit  to  a plantation  on  the 
Island  of  Hawaii  on  April  10,  1906,  wrote:  ‘‘This  pest(  re- 
ferring to  Perkinsiella)  has  begun  to  become  very  much  reduced 
in  comparison  with  the  last  visit  in  December,  1905,  but  is  still 
causing  here  and  there  serious  damage.  The  egg-parasites  are 
multiplying  more  and  more  and  are  distributed  over  the  whole 
field  wherever  there  are  Perkinsiella.” 
One  year  later  the  same  entomologist  having  visited  the  same 
plantation  reported  that  Perkinsiella  was  almost  entirely  destroyed 
and  that  the  parasites  were  as  few  as  the  hosts,  but  that  they  were 
to  be  found  wherever  there  was  Perkinsiella  left. 
Besides  these  species  of  egg  parasites  the  following  now  attack 
Perkinsiella : PL  apla  gonatopus  critiensis,  collected  by  Muir  in 
1907  on  the  Fiji  Islands;  a Pseudo gonatopus  sp.  sent  by  the  same 
from  China,  and  another  Pseudo  gonatopus  sp.  which  Koebele 
(1908)  obtained  in  Mexico  from  a species  of  the  genus  Liburnia 
and  which  has  adapted  itself  in  Hawaii  to  parasitise  Perkinsiella. 
Also  species  of  Dryinidae,  native  of  Kauai  and  Oahu,  Echtrodel- 
phax  fairchildii,  P.,  and  formerly  parasite  of  other  Fulgorida,  has 
adapted  itself  to  Perkinsiella  and  has  been  distributed  on  all  the 
other  islands  of  the  group.  Of  the  predatory  Coleoptera  : Verania 
frenata  and  V.  lineola,  Callineda  testudinaria,  raised  excellently  in 
cages  and  distributed  in  large  numbers,  nothing  certain  can  be 
said  and  the  same  applies  to  the  numerous  other  parasites  which 
arrived  alive  at  Honolulu  and  which  were  collected  in  part  on  an- 
other voyage  on  which  the  Sugar  Planters’  Association  had  sent 
the  Assistant  Entomologist  Muir  to  the  Fiji  Islands  in  1906  and 
later  on  to  China. 
The  practical  result  of  the  introduction  and  acclimatization  of 
the  imported  parasites  has  been  so  good  that  all  anxiety  on  account 
of  Perkinsiella  seems  now  dispelled  and  so  it  appeared  also  to  me, 
having  seen  a number  of  parasites  hatch  from  the  eggs  of  leaves 
from  different  localities. 
Only  the  practice  of  burning  the  cane  leaves  in  the  fields  kills 
many  parasites  while  the  Perkinsiella,  being  able  to  fly,  can  save 
themselves  easier  and  this  hinders  their  reduction  to  a smaller 
number,  but  already  entomologists  are  studying  to  find  a wav  to 
