THE MEDITERRANEAN FRUIT FLY. 9 
no food; but if they can secure the juices of fruits or the honeydew 
of insects, which form the bulk of their food, they may live long 
periods. Two flies lived for 230 and 315 days, respectively. But as a 
ride life is much shorter, although many live to be four to six months 
old. Many die when they are very young, even if they have had food. 
In Honolulu females begin to lay eggs when 4 to 10 days old, 
and, like hens, only much more faithfully, continue to develop and 
lay eggs in fruits almost daily so long as they live. A female may 
lay on an average from 4 to 6 eggs a day, 22 eggs being the largest 
number known to have been laid by a fly during any one day. On 10 
consecutive days one fly laid 8, 11, 9, 6, 8, 3, 3, 3, 3, and 9 eggs; 
another laid 0, 5, 14, 8, 13, 10, 6, 4, 4, and eggs. The largest 
number of eggs laid during life by a single female kept in the labo- 
Fig 9.— Mediterranean fruit fly: a, Larvae, or maggots; 6, pupae, or chrysalids. Twice naturalsize. 
(Original.) 
ratory was 622. This fly lived only 153 days. It is probable that 
800 eggs, or even more, may be laid by single hardy females under 
favorable conditions. 
It is also important, from the standpoint of control, to know that 
females deprived of a chance to lay eggs in fruits for a period of four 
to six months when certain crops are not in season have the power 
to begin depositing eggs as actively as younger flies when fruits 
sufficiently ripe become available for oviposition. Thus one female 
kept in the laboratory for the first five months of her life without 
fruits in which to lay eggs laid 11, 4, 9, and 9 eggs during the first 
four days of the sixth month of her life when fruits were placed in 
the cage with her. 
CLIMATIC CONDITIONS FAVORING RAPID INCREASE IN HAWAII. 
The time required by the fly to pass through the egg, larva, and 
pupa stages depends very much upon the climate. The climate of 
Honolulu and of the coastwise regions of Hawaii in general is very 
