2 BULLETIN 491, U. S. DEPARTMENT OF AGRICULTURE. 



to the lack of concerted and intelligent action among the oriental 

 market gardeners. The purpose of this bulletin is, therefore, to call 

 attention to the unprecedented ravages of this pest in the Hawaiian 

 Islands and the danger of introducing it into the mainland United 

 States, and to record new facts concerning its biology, rather than 

 to offer a satisfactory method of control. 



ORIGIN. 



The true Dacinae, the subfamily of the Trypetidae, to which the 

 melon fry belongs, are almost without exception tropical or subtrop- 

 ical in distribution. Most of the well-defined genera have been found 

 by Bezzi to show a restricted area of habitation and to be almost 

 exclusively confined to the Old World. Indeed, the few species which 



Fig. 1. — The melon fly (Bactrocera cucurbitae) : Adult female. Greatly enlarged. 



(Original.) 



are recorded from widely separated countries have reached their 

 present distribution not by natural spread but by the assistance of 

 man. The melon fly is a good example of a pest known to have been 

 artificially introduced to new countries. Bezzi. who has given the most 

 complete and recent review of fruit flies, stated in 1913 that the orig- 

 inal home of the melon fly is India. Other entomologists who have 

 traveled in the Orient for the purpose of making fruit-fly studies, 

 particularly Compere. Froggatt, and Muir, agree with Bezzi as to 

 its Indian origin. Perkins stated that its true home is either Japan 

 or China, but this statement was made in 1902, before the discovery 

 of the melon fly in India and before the studies of Bezzi were 

 undertaken. 



