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died  there  before  they  could  be  favorably  liberated.  Other  in- 
dividuals he  sent  at  the  end  of  1891  and  still  others  he  carried  in 
the  summer  of  1892,  leaving  them  at  Haywards,  California,  but 
up  to  now  nobody  seems  to  have  established  the  acclimatization 
of  this  species. 
On  the  other  hand  Koebele  was  more  fortunate  with  a 
Coccinellid,  Rhizobius  ventralis,  Erich.,  which  he  found  common 
in  southern  Australia  and  in  Victoria  living  on  various  species  of 
scale  bugs  among  them  of  the  genus  Lecanium.  Koebele  sent 
many  specimens  to  California  in  1891-1892  where  they  became 
acclimated  and  spread  over  the  whole  state  multiplying  abund- 
antly, especially  in  the  coast  districts,  at  the  expense  of  Lecanium 
oleae. 
The  same  Rhizobius  ventralis  was  later  brought  to  Hawaii 
where  it  attacks  various  species  of  Lecanium  and  in  winter  also 
Pseudococcus  nipae,  Mask.,  while  in  summer  it  retires  to  the  hills. 
Another  Coccinella,  Orcus  australasiae,  Boisd.,  was  during  the 
same  time  introduced  from  Australia  to  California  by  Koebele 
and  although  it  lives  on  other  scalebugs  too,  it  has  given  in  some 
parts  of  California  goods  results  also  against  Lecanium  oleae. 
Orcus  chalybeus,  Boisd.,  was  sent  by  Koebele  to  California  and 
became  acclimated  there,  seemingly  feeding  rather  more  actively 
than  the  preceding  species,  attacking  Diaspinae  and  young  Le- 
canium. 
The  following  Coccinellids  (all  described  by  Blackburn)  were 
also  sent  there  from  Australia : Rhizobius  dorsalis,  debilis, 
coecus  and  Cyrena  nigellum,  Scymnus  flavifrons,  sydneyensis, 
aiistralsiae,  greenslandicus,  but  they  seem  not  to  have  become  ac- 
climated. 
Besides  these  predatory  coleoptera,  the  work  of  an  Hymenop- 
teron  was  sought,  Scutelhsta  cyanea,  Motsch.,  which  in  the  larval 
state  eats  the  egsg  of  Lecanium  and  also  of  Ceroplastes.  Craw 
wrote  to  C.  P.  Lousbury,  entomologist  of  Cape  Colony,  asking 
him  to  send  specimens  from  that  region.  In  October,  1901,  a 
good  number  of  them  was  sent  to  Craw  in  California ; seventeen 
of  them  arrived  alive  and  proved  sufficient  to  obtain  a first  genera- 
tion. The  descendants  of  these  were  distributed  in  1892  and 
from  these  specimens  could  be  obtained  for  gradual  distribution 
over  the  whole  state  where  it  is  now  splendidly  established  de- 
stroying a great  number  of  Lecanium  and  Ceroplastes  and  seems 
to  have  there,  in  distinction  from  Italy,  no  parasites. 
G.  Gompere,  another  practical  entomologist  enthusiastic  for  the 
natural  method  introduced  from  Australia  to  California  a chal- 
cidid,  Hymencyrtus  Crawii,  Ashm.,  endophagous  parasite  of 
Lecanium  oleae.  This  hymenopteron  seems  to  have  established 
itself  in  some  parts  of  California  giving  also  its  contribution  to  the 
destruction  of  the  scalebug  under  discussion. 
Lecanium  oleae  has  in  California  another  endophagous  para- 
