44 



DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



of one specimen of the first brood in 190S was secured. This larva 

 hatched June 20. It emerged from fruit and started to make its 

 pupal case July 10. and had transformed to pupa by July 12. making 

 the larval stage 22 days in length. This period coincides quite 

 closely with the average larval period secured for several larva? of 

 the first brood during the season of 1909. which was 21.25 clays. 



The earliest record of emergence of first-brood moths was made 

 on July 13 from a pupa found July 1 on a leaf in the rearing cage 

 in 1908. This is 10 days earlier than the record for other moths 

 from the same source (see Table XX). The emergence record in 

 this table is doubtless somewhat abnormally early, owing to the fact 

 that the temperature in the rearing cage was several degrees higher 

 than outside. 



Table XX. — Time of emergence, of first-brood moths of the grape-berry moth. Xorth East. 



Pa.. 1908. 



Date of Num- 

 emer- i ber of 

 gence. moths. 



Date of 



emer- 

 gence. 



Num- 

 ber of 



moths. 



Date of 



emer- 

 gence. 



Num- 

 ber of 

 moths. 



Date of 



emer- 

 gence. 



Num- 

 ber of 

 moths. 



Julv 23 * 3 



Julv 24 4 

 Julv 2o 8 



Julv 26 

 July 27 



Julv 28 



26 



31 



9 



Julv 29 



Julv 30 

 Julv 31 



4 

 2 



3 



Aug. 1 



Total . 



1 



91 



SUMMARY OF LIFE-HISTORY STUDIES OF THE GRAPE-BERRY MOTH. 



Life-history studies of this pest at Xorth East. Pa., during the 

 seasons of 1907. 1908, and 1909 indicate that there is only one full brood 

 of larva? and a partial second brood each year in the vineyards of the 

 Lake Erie Valley. The partial second brood of larvae, however, is 

 larger in numbers than the full first brood, probably on account of 

 the large number of fatalities that occur among the pupae during 

 the whiter season which tends materially to lessen the number of 

 moths that emerge in the spring. The moths from overwhitering 

 pupa? commence to emerge about June 1. (See fig. 15. with curve 

 showing length of the various stages of the grape-berry moth for the 

 season of 1909.) Less than 25 per cent of these spring-emerging 

 moths appear before the grape is in full bloom. The total emergence 

 period of the spring moths is about 60 days. As the period of maxi- 

 mum emergence is from June 10 to July 10. it overlaps into the emer- 

 gence period of the first brood. About 4 to 6 days elapse between the 

 emergence of the moths and the deposition of eggs. The egg stage of 

 the first brood covers about 6 days. The larval period covers about 

 23 days and the pupal stage about 13 days. A small percentage of 

 the pupa? of this first brood pass the whiter. The moths of the first 

 brood commence to emerge during the latter part of July, the maxi- 

 mum number emerging from about August 10 to September 1. The 

 period of incubation of the second-brood eggs is a little longer than 



