56 BULLETIN 491, U. s. DEPABTMENT OF U3BIGULTTTBE. 



loving rather than by long-sustained flights. During the warmest 

 seasons they are active in feeding and ovipositing chiefly during the 

 early morning and late afternoon hours. In captivity they mate 

 about sunset and when fed upon papaya and water, copulate only 

 when about 20 or more days old, with the mean temperature av- 

 eraging 75.5° F. and the relative humidity (59.3 per cent. No eggs 

 were obtained from females under these conditions until 32 days 

 after emergence. During the winter, also, when fed upon papaya 

 and water, when the mean temperature was 71° F. and the relative 

 humidity 78.5 per cent, no eggs were deposited until 44 days after 

 emergence. However, when fed on cucumber, in captivity, mating 

 will commence when the adults are only 10 days old and egg-laying 

 begins the following day or only 11 days after emergence, when 

 the mean temperatures average 76.4° F. and the relative humidity 

 is 69.1 per cent. Having once begun ovipositing, adults continue 

 to deposit batches of from 1 to 37 eggs every few days through- 

 out life. One female deposited eggs when 398 to 100 da} 7 s old. An- 

 other, emerging on May 25, 1914, deposited 687 eggs between July 

 15, 1914, and February 27, 1915. It is estimated that particularly 

 hardy individuals ma} 7 deposit as many as 1,000 eggs. The average 

 number of eggs deposited is much less and extremely variable. 



Adults deposit their eggs within the tissues of the host fruit in 

 cavities made with the aid of a sharp ovipositor. Eggs may be 

 deposited in all portions of the plant and fruit, including the crown, 

 leaf petioles, stalks, and blossoms. If deprived of host plants adults 

 will oviposit, although less frequently, upon other objects, at least 

 in confinement. They were able to keep alive by feeding on the 

 food supplied them in the laboratory during a period of what hap- 

 pened in experimental work to be from 13 to 31 to 37 Aveeks when 

 no host plants were available for oviposition, and began ovipositing 

 at a normal rate as soon as host plants were available. 



Larvae upon hatching usually burrow to the center of the host 

 plant or fruit, although the place where the} 7 feed is determined 

 largely by the moisture content of the host. In young seedlings they 

 may burrow into the taproot and kill the plant. In succulent plants 

 they burrow through the leaf petioles and stalks and bring about 

 a progressive pruning back of vines by causing the death of affected 

 parts. The staminate and pistillate bloom and the fruits are vari- 

 ously affected, as described and illustrated elsewhere. After passing 

 through three instars the larvae leave the host to pupate in the soil, 

 usually beneath the host, at a depth ranging downward to 2 inches. 

 Larvae are aided in leaving the fruit and seeking suitable places for 

 pupation by their ability to jump, in stages, from 6 to 8 inches. If 

 they are not able to enter the soil they will pupate upon any hard 

 surface, such us a floor, corners of fruit cases, burlap coverings, etc. 



