32 



DECIDUOUS FKUIT INSECTS AND INSECTICIDES. 



Table II gives a record of oviposition by spring-emerging moths 

 secured during the season of 1909. This table gives the number of 

 days between emergence of the moth and the first oviposition and 

 also the number of days between emergence and the last oviposition. 

 The minimum period before first oviposition was 4 days; the average 

 6.6 days; the maximum 13 days. The average period between the 

 first and last ovipositions was 7.1 days. The longest period between 

 emergence and the last oviposition was 18 days. 



Length of life of spring brood oj moths. — Records from our rearing 

 cages show that many of the moths will live in confinement for a 

 number of days, especially when food in the form of honey or sweet- 

 ened water is supplied. Table III gives the length of life of 76 

 moths, showing that the minimum life period was 4 days, the average 

 12.9 days, and the maximum 23 days. The average length of life of 

 the moths recorded in this experiment very closely approximates 

 that of the moths recorded in Table II, which was 12.7 days. 



Table III. — Length of life of moths of the spring brood of the grape-berry moth in con- 

 finement, with food, at North East, Pa., in 1909. 



Number of 

 moths. 



Date- 



Length 

 ofUfe. 



Number of 

 moths. 



Date- 



Length 

 of life. 



Emerged. 



Dead. 



Emerged. 



Dead. 



4 



June 19 

 ...do 



July 3 

 July 6 

 July 7 

 July 8 

 July 9 

 June 29 

 Julv 1 

 July 3 

 July 9 

 July 8 

 July 10 

 July 12 



Days. 

 14 



17 1 



18 1 



19 

 20 

 9 

 11 

 13 

 19 

 15 

 17 

 19 



3 



June 23 j July 16 

 June 24 Julv 2 



Days. 

 23 



8 



13 

 15 

 17 



8 



10 

 11 

 12 



4 

 11 

 13 



4... 



10 



4 



2 



1 



6 



...do 



...do.... 

 ...do.... 

 June 20 

 ...do.... 



4 . 



...do 



...do.... 

 ...do.... 



July 4 



...do 



...do.... 

 ...do.... 



July 7 

 July 9 

 July 11 

 July 12 

 July 14 

 July 15 

 July 16 

 July 17 

 July 24 

 July 26 



5 



2 



1 



1 



8 



2 



6.. 



1 



2 



...do.... 

 ...do.... 

 June 23 

 ...do 



...do.... 



3 



July 13 

 ...do 



...do.... 



2 



2 



Total number of moths 76 



Length of life: 



Average days. . 12. 9 



Maximum do 23 



Minimum do 4 



FIRST GENERATION. 



Incubation period oj first-brood eggs. — Table IV gives a record of 

 the length of the egg stage for 21 eggs of the first brood deposited 

 on grape berries in the field rearing cage. The minimum length of 

 the egg stage for this number of eggs was 4 days, the average 6 days, 

 and the maximum 8 days. 



