824 



Pomona College Journal of Entomology 



Figure 2r)8 is a diagram showing some of the most important host fruits 

 in Hawaii ami the seasons when they are in bearing. The circles and portions 

 of circles represent periods during the year when the host fruits are to he 

 found. It will he noticed that the wild guava and Chinese orange have a 

 continual cycle while the eugenias, strawberry guavas and Kona oranges have 

 certain main seasons with intermitt-ent fi'uiting between. It is difficult to 



Figure 259 



establish seasons for many of these fruits as they fruit at different times in 

 diff-erent localities, and with some it is not an uncommon sight to see flowers, 

 green and ripe fruit on the trees all at once. However, it can be seen that at 

 any time of year there are at least six host fruits in bearing, one or two of 

 which are wild. Is it any wonder that the fly has continued to increase in 

 numbers in Hawaii, defying all methods of control? 



Figure 259 shows a corresponding diagram made with Southern Cali- 

 fornia conditions in mind. Tiie fly has been bred from all the fruits shown in 

 the diagram, those marked with D in Hawaii, and those marked with X 



