406 Annals Entomological Society of America _ [Vol. V, 
The first lot of five hundred Mediterranean fruit flies were 
set free during light rains followed by frequent heavy showers 
and yet thirty-one of these marked specimens were captured in 
the kerosene traps; apparently the drops of rain striking the 
fruit flies did not disable them for flight. The last lot of five 
hundred marked males was liberated while a south-west wind 
was blowing away from the city of Honolulu towards the moun- 
tains and yet eleven of these marked individuals were captured 
in kerosene traps located in the outskirts of the city at dis- 
tances varying from a mile to a mile and a half from the point 
of liberation. The explanation of this fact may be that some 
of these marked insects were caught up by changes of wind 
carrying them first towards the mountains and then back 
again into the city of Honolulu, 
Marked Mediterranean fruit flies were captured at distances 
varying from a quarter of a mile to a mile and a half from their 
respective points of liberation. In all probability some of the 
flies which had been set free during a strong wind were caught 
up and carried far into the city of Honolulu or even way beyond 
into the sea miles away from the points of liberation. In 
numerous instances kerosene traps were kept in the same tree 
for a period of two weeks and marked specimens were captured 
from time to time. The explanation of this fact may be that 
the fruit flies did not make one continuous flight from the point 
of liberation to the trap in which they were caught, or that the 
trypetids were not immediately attracted to the kerosene after 
getting into the vicinity of them. 
On account of using male fruit flies only, the argument may 
be raised that there is no evidence from this experiment that the 
female flies are carried by the winds. How would the rapid 
distribution of the pest in the guava belt, often at high altitudes 
in the mountains, be explained? In all probability the answer 
to this question is best explained by the fact that the wind, 
which is such a potent factor in influencing the flight of the 
males, as demonstrated by this experiment, has carried the 
females as well as the males into the guava belt. 
Clean culture to control the Mediterranean fruit fly as 
carried on by the Board of Agriculture in the Hawaiian Islands 
consists in stripping all fruit trees, except mangoes and papaias 
of infested and ripe fruit and also of picking up and destroying 
