THE GRAPE ROOT- BORER. 



25 



ACTIVITIES OF THE MOTHS. 



It has been stated that in North Carolina the moths are on the wing 

 from the middle of June until the middle of September (3) but ob- 

 servations indicate that in West Virginia the period of flight is not 

 so long. Table I shows the dates on which moths were first and last 

 seen in three different years in West Virginia. 



Table I. — Period moths of the grape root-borer are on the wing, West Virginia. 



Year. 



First 

 seen. 



Last 

 seen. 



Number of 



days on 



wing. 



Average 



number of 



days. 



1907 

 1916 

 1917 



July 24 

 July 20 

 July 25 



Aug. 10 

 Aug. 17 

 Aug. 17 



18 

 29 



24 



123.3 



The records set forth in Table I show that in the locality where the 

 present investigation was made the moths v are probably on the wing 

 a little less than 30 days, instead of 90 days, as reported from North 

 Carolina. 



The moths issue from the cocoons on bright, warm days, usually 

 about the middle of the forenoon. Of 11 females observed, all left 

 the cocoons between 9 a. m. 1 and 11 a. m. The males after issuing 

 rest for a while on some object near the discarded cocoon and then 

 take flight, but the females are less active and usually remain quietly 

 near the place of emergence several hours to await the coming of the 

 males. Several females that were kept under observation were seen 

 to elevate their genitalia, evidently sending forth a scent to attract 

 males. Almost instantly after this act was begun by the female a 

 swarm of males would appear and copulation would soon take 

 place. Usually the pair would remain connected for 2 or 3 hours, 

 and on the morning following egg laying would begin. In one case 

 observed copulation lasted 2 hours and 45 minutes and in two cases 

 3 hours and 40 minutes each. Two or three of the females did not 

 attract and receive the males until the morning following their 

 emergence from the cocoons. One group of excited males that gath- 

 ered around a female contained a single male of the squash-vine 

 borer, Melittia satyriniformis. This moth grasped the female and 

 attempted to pair with her after she had united with a male of her 

 own kind. 



In ovipositing the females make short flights, alighting on the 

 canes or leaves of grapevines, or, more frequently, on grass, weeds, or 

 straws under or near the vines, and deposit in each place one or more 

 eggs. Sometimes four or five eggs will be placed together and at 

 other times the female will crawl over the surface of a leaf or along a 



1 Referencss to clock time refer to standard tirre. 



