BIOLOGY OF THE PAPAYA TRUIT 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 

 ofpupse. 



Number 

 of males. 



Number 



of 

 females. 



Total 

 emerged. 



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 (PI. I, A) is a wasplike 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 daj^s. 

 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 



5 For original description see Gerstaecker, A. Beschreibung einiger ausgezeichneten 

 neuen Dipteren aus der familie Muscariae. In Ent. Zeitung Stettin, Jahrg. 21, No. 4/6, 

 p. 194-195. 1860. 



101920—22 2 



