385 
Notes on Insect Pests in Samoa. 
BY O. H. SWEZEY. 
(Presented at the meeting of November 1, 1925.) 
While in Samoa four weeks during September, 1923,.every 
opportunity was taken to make observations on insect pests of 
economic importance there. 
Apparently the most destructive pests are those of the coco- 
nut and banana, and they appear to be such as have compara- 
tively recently arrived there from elsewhere, probably from 
other Islands of the South Pacific. 
The worst pest on sugar cane is the borer, the same kind 
that we have in Hawaii. As cane is grown in Samoa only for 
thatching the native houses, the damage done by the borer is 
not taken so seriously as if it were a commercial crop. 
INSECTS ON SUGAR CANE. 
Perkinsiella vitiensis Kirk. 
This leafhopper was usually to be found in patches of sugar 
cane, though not abundant enough to be injurious. In fact, the 
insects themselves were rather so scarce as to be difficult to find, 
but their presence was known by the discoloration of the mid- 
rib of the leaves where eggs had been deposited. Very few 
eggs were found anywhere, and I failed to find any that were 
parasitized. However, a few of the little round exit holes were 
found which indicate where the egg-parasite Ootetrastichus 
had issued. This was very likely the same species ( Ootetras- 
tichus beatus Perkins) that occurs in Fiji. The adult parasite 
-oviposits in eggs of the leafhopper. In developing, the para- 
\site larva consumes the leafhopper egg in which it has hatched, 
it then eats the other two to seven eggs of the same cluster of 
jleafhopper eggs. Having obtained its growth the larva trans- 
/ forms to the pupa and adult in a small cavity in the leaf tissue, 
/ and gnaws the tiny round exit hole to make its escape when 
fully matured. This egg-parasite was introduced from Fiji 
to Hawaii in 1905 where it rendered valuable assistance in 
checking the cane leafhopper (Perkinsiclla saccharicida \irk. ) 
Proc. Haw. Ent. Soc., V, No. 3, December, 1924. 
