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in the district is the control exerted over the molon fly by the newly intro- 
duced parasite Opius fletcheri. This parasite was liborated in the district in 
June, 1916, At the present time the fly is so reduced there that it is in no 
sense destructive, I examined carefully 400 cucumbers of various sizes, 28 
young watermelons, 20 young muskmelons, 21 young pumpkins,and 2,456 ripe wild 
cucumbers, Momordica sp, I found only one egg puncture in one of the cultivated 
cucumbers, which was a surprising and wholly unexpected condition. None of the 
cucumbers had scars or deformities that are so characteristically seen in all 
gardens where the melon fly is present. None of the melons or the pumpkins 
were touched by the melon fly, nor could any injured or stung blossoms be found, 
The wild Momordica grows luxurianthy over large areas in Kona, Of the 2,456 
fruits examined, 266 contained eggs or larvae of the melon fly. Most of these 
infested ones were found in an isolated spot in the center of an overgrown, 
abandoned cotton field, From the infested Momordicas a total of 676 melon fly 
larvae were secured, These were heavily parasitized by 0. fletcheri, the para- 
‘sitism amounting to 96.9%, Those engaged in gardening in the district are 
very much pleased with the new condition and report all along the line very 
favorably. I consider this control to be the result of two factors, One is the 
work of the parasite and the other is the presence of the great quantities of 
wild Momordica everywhere, The Momordica fruits heavily throughout the year 
and is certainly a. very favored host of the melon fly. The fruits are univer~ 
sally small,seldom being more than an inch in diameter, This permits the fly 
to be present constantly and in fruits small enough to allow the parasite to 
reach most of the larvae, The parasitism is thus high and the flies that do 
reach maturity have a great abundance of a natural host constantly at hand to 
absorb their eggs, The cultivated gardens scattered through the district are 
thus attacked by a greatly reduced number of flies and these are not necessarily 
in a condition to deposit an excessive number: of eggs for they must be cont inu- 
ally ovipositing in the wild cucumbers in all directions, both in and about 
the gardens. In May, 1916, I examinee 442 wild cucumbers at the same locality 
_where the above were examined and just a few weeks prior to the liberation of 
' the parasite, Of these, 248 were well infested, The comparison with the pres~- 
ent condition is interesting, Opius fletcheri is well established about Hono- 
lulu now and has checked the melon fly to some extent, The Chinese gardeners 
_ claim that they are not having quite so much trouble now as before, but just 
how much the improvement is I can not say, I am making some investigations of 
this now, 
HOHOHX The fruit fly is not very destructive in the coffee district at 
present. The infestation of the coffee cherries is really low and is slightly 
lower than I have ever seen it before, From 13,601 berries collected, a total 
of 12,024 fruit-fly larvae emerged. This is an average infestation of 0,88 
larvae per fruit, In January, 1917, from 13,057 berries a total of 14,715 fruit 
fly larvae were secured. On this trip I found the parasitism very high, The 
total parasitism averaged 92.9%, distributed among the three species of para- 
' sites as follows: Opius humilis 16.7%, Diachasma tryoni 68.7% and Diachasma 
fullawayi 74. The coffee was largely picked by the time I arrived so that the 
% parasitism in the larvae still present in the unpicked berries was no doubt 
somewhat higher than it would be before picking time. Still the infestation was 
not high. 

, Our paper on the interrelations of the fruit-fly parasites here has 
caused considerable discussion among certain of the entomologists in Hawaii, 
notably those who were instrumental in introducing the parasites, In order 
