The Hawaiian star. [volume] (Honolulu [Oahu]) 1893-1912, 1912-01-12
DR.. SEVERN TELLS ABOUT
FRUIT FLY INVESTIGATIONS

tie value, as the proportion OF bene-
fetal parasites was very small. AS to
whether or not the Mediterranean
fruit fly breeds in the Chinese banana
as it grows on the plantations, the
doctor was unable to tell, as his at
tempts to set oil traps in the banana
trees between here and Waikiki were
not allowed to be carried out.
Spraying Is Effective.
In regard to the benefit of spraying,
DR.. SEVERN again brought forth
charts which showed the vast differ
ence in the number of flies caught be-
fore and after the process. By the use
of sixteen pans throughout period
of thirty-five days before spraying,
there were caught thirty-six females
and 10,203 male flies, while with the
same number of traps throughout the
same space of time after spraying
there were caught only eight females
and TIA male flies. But though the
number of fruit flies was much dimin-
ished by spraying, it seemed, if any
thing to increase the number of pre-
daceous insects, for where before
they caught but fifty-two, after the
spraying there were sixty-two found
in the traps.
1t will be noticed that there is
great difference in the numbers of
male and female caught, which fact
the doctor explained, upon being
questioned after the lecture, as not
being due to the comparative numbers
of the two sexes Matched, but rather
to the oils lack of attraction for the
female sex. This they have tried to
eliminate by using many varieties of
cheap oils but to no purpose. These
tests, however, DR.. SEVERN maintains
are not to be relied upon, as there is
a necessity of much work before any
degree of accuracy may be attained
Danger to California.
Next the danger to California from
the pest was brought out, which the
Doctor believes real because, though
it might be improbable that the fruit
fly would be carried by means of ba-
nanas' shipped green, the Cinnamon
were not at all careful, and would
often ship ripe or bruised fruit, in
which it is not only possible but
probable that the animal would
breed, "All fruit being shipped from
here to San Francisco" asserted Dr.
SEVERN, should undergo the inspec-
ton of an expert entomologist, who
should never relax the vigil. How
, ever" the lecturer added, because
fruit fly eggs, extracted by vivisection
and placed in the banana, should
hatch affords no reason to believe
that this would be the case under
natural circumstances.
Papaia Susceptible.
In going over the fruit in which
the fruit fly breeds, the doctor
brought out the fact that papaia is
one of the most fertile, and that the
insect is not at all particular in Sc
lecting those that are bruised, but
will accept with equal energy one
that is perfect though ripe; and also
that grape fruit, which is not men
toned in the expectation regulations,
is one of their favorite.. breeding
places, AS to the pineapple, there
were vague hints leading to what
might be the case, but no positive
statement was made.
h Thorough Inspection Demanded.
Finally Dr. SEVERN went again into
the question of inspection, citing the
system of San Francisco as an exam
pie that should be carried out here,
for the local inspectors, he claimed,
are failures on account of their negli-
gence in performing their duties. The
luggage of the first cabin passengers
on the inter-island steamers is seldom
if ever looked into, while that of the
steerage passengers receives a hur-
ried rummaging. why not" he con-
cluded, protect the still fortunately
exempt islands from the ravages Of
the pest?"
That he had been unable through
lack of efficient assistance, to con
duct experiments upon the wild fruits
of the higher attitudes, DR.. SEVERN
regretted That he was withheld from
pursuing his tests on the banana he
seemed to resent.