BIOLOGY OF THE PAPAYA FRUIT FLY. 5 
eral hundred puparia placed in jars, some of them reared from larvae 
and others gathered in the soil under trees, gave results as shown in 
Table I. 
Table I. — Males and females of Toxotrypana curvicauda maturing from puparia 
placed in jars. 
Number 
of pupae. 
Number 
of males. 
Number i Total 
females, j emer S e(L 
Total 
died. 
870 
279 
281 560 
310 
Thus it is seen that only 64.3 per cent matured into adults, while 
35.7 per cent died. Of the number maturing practically 50 per cent 
were males and 50 per cent females. 
Practically all the adults emerge from the soil in early morning 
just before daylight. Very rarely will one emerge between sunrise 
and midnight. The adults often carry the pupal case to the surface 
of the ground before freeing themselves from it. Only a few minutes 
are then required for their complete development. 
ADULT. 5 
The adult of this species (PL I, A) is a wasp like fly, very much 
resembling in coloration and general appearance the wasps of the 
genus Polistes. The body is yellow and brown, marked with black, 
and the females are made strikingly conspicuous by a long, curved 
ovipositor, even longer than the body itself. There is considerable 
variation in the size of the flies, but they average about 12 mm. in 
length. The ovipositor of the female varies from 10 to 14 mm. in 
length. 
The flies exhibit a rather rapid flight and walk with a quick 
nervous motion. The females are not often seen on bright days but 
appear about the trees to lay their eggs in the late afternoon or even- 
ing. They show a negative reaction to sunlight and always seek the 
shady side of the tree or fruit. Although sometimes seen during the 
morning and noon hours, the greatest flight occurs about an hour 
before sunset. The males, however, are more active on bright days. 
Both sexes are easily disturbed when resting on the fruits. 
The life of the adult flies is probably only a few days in length. 
They have been kept alive in captivity for 31 days when properly 
fed, although the average is very much less. The flies will eat any 
kind of sugar sirup and the pulp and juices of some fruits, but they 
never appear to be attracted by any food. Many will die without 
B For original description see Gerstaecker, A. Beschreibung einiger ausgezeichneten 
neuen Dipteren aus der familie Muscariae. In Eat. Zeitung Stettin, Jahrg. 21, No. 4/6, 
p. 194-195. 1860. 
101920—22 2 
