1914] Melon Fly, Dacus cucurbitae. 191 
20. Respiration of larve in liquafied pulp.—Melon fly 
larve in a decayed tomato were observed to obtain a fresh 
supply of air by pushing the posterior spiracles above the sur- 
face of the liquified pulp. The stem of this tomato had been 
cut out and many maggots were found suspended from the 
surface film with their bodies immersed in the liquid. When 
the finger was snapped against the tomato, the larvae wriggled 
down into the liquified pulp, but sooner or later, they would 
come up to the surface film to breath. 
21. Jumping habit of larve——When nearly, full-grown, 
melon fly larvae are removed from the host, they exhibit a 
peculiar habit of jumping, but this behavior is not manifested 
by the smaller maggots. The larve curl the body in a circle 
(plate XXVIII, fig. 17), the jaws attach to the posterior end 
of the body, and then by a sudden muscular relaxation, they 
spring about six to eight inches into the air. 
22. Feeding habits of the melon flies.—As a rule, Dacus feeds 
during the early morning from sunrise to about ten o’clock. 
During the hottest part of the day thousands of these insects 
may be found at rest under large leaves of plants in or near an 
infested field of cucurbits. The flies were frequently found 
several hundred feet away from their breeding grounds, feeding 
upon the flowers of the glue bushes, sunflowers and Chinese 
bananas. Nota single fruit fly was ever seen entering and feed- 
ing within the carolla of pumpkin flowers or morning glories, 
but after a rain, specimens were occasionally observed lapping 
up the small droplets of water on the lobes of the corolla of 
morning glories. Melon flies feed upon the juices of injured 
or infested cucurbits in the field. Many individuals were ob- 
served feeding on the juices exuding from sweet corn. One adult 
was noticed feeding on a dead and partly decomposed cater- 
pillar. 
When a piece of the rind of a pumpkin was removed, large 
numbers of the pest were attracted to the exposed pulp and fed 
upon the exuding juices. When a common house fly also 
visted the pulp to feed and approach a melon fly already en- 
joying a meal, the latter would dart forward and chase the former 
away, but when laying eggs the fruit fly would not withdraw its 
ovipositor even when the house fly crawled over its body. 
