MEDITERRANEAN FRUIT FLY IN HAWAII. 21 



packing crates and old burlap, etc., recently used as containers are 

 apt to carry the pest and should be guarded against until experience 

 for the locality and temperature concerned has proved that the 

 adults have emerged. Certain instances of spread in western Aus- 

 tralia are believed to have occurred through carelessness in the use 

 of second-hand packing cases. In Hawaii, Hilo grass (Paspalum 

 conjugation) , gathered from beneath guava bushes (PL XIV, fig. 1 , in- 

 sert), was discontinued as a packing material for bananas for fear 

 pupse of the fruit fly attached to it might reach California. 



COLD STORAGE. 



While cold-storage temperatures may be used to render fruits free 

 from danger as transporters of the fruit fly (see p. 108), the use of 

 temperatures fluctuating above 38° F. may be one of the greatest aids 

 in prolonging the duration of fruit-fly life within host fruits. 



WIND. 



That adult males of the Mediterranean fruit fly can be carried by 

 the wind distances varying from one-fourth to 1| miles from points 

 of liberation has been demonstrated by Severin, who states further 

 that in all probability some of the flies which he had set free at the 

 head of Manoa Valley "were caught up and carried far into the city 

 of Honolulu, or even away beyond into the sea, miles away from the 

 points of liberation." The writers agree with Severin as to the 

 ability of winds to carry adults considerable distances. The dis- 

 covery by Mr. H. T. Osborn of an adult upon the summit of Kona- 

 huanui (elevation 3,105 feet), the highest peak of the range separating 

 the windward and leeward sides of the island of Oahu, and at a con- 

 siderable distance above the highest range of host plants, makes it 

 easier for the writers to believe that the few adults which they 

 captured in traps in the scant vegetation on the leeward shore line, 

 and at considerable distances from known sources of infestation, 

 during very windy weather, were specimens caught on the windward 

 side in strong ascending air currents and carried entirely across 

 Oahu. There is no doubt that the adult on Konahuanui observed 

 by Osborn was transported thus from the lower windward levels. 



HOST FRUITS. 



The writers know of no edible fruit commonly grown in the 

 Hawaiian Islands, except the pineapple, that is not subject to attack 

 by the Mediterranean fruit fly. From a practical trade standpoint 

 the banana should not be considered a host when grown and shipped 

 in accordance with the regulations of the Federal Horticultural 

 Board. 



