24 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 
LIFE CYCLE OF THE FIRST GENERATION. 
From the earliest appearing eggs in spring, about April 15, to the 
first appearing moths, June 17, gives some 63 days as the approxi- 
mate length of the life cycle of the first generation. The laboratory 
records for individuals kept in breeding cages give a life cycle of 71 
to 78 days. This, however, is based on only 12 individuals, which 
completed the cycle, and are recorded in Table VI. Careful obser- 
vation indicates the length of time of the first generation to be from 
60 to 70 days. 
THE SECOND GENERATION. 
SECOND-BROOD EGGS. 
Time of oviposition —A number of moths which emerged at the 
Jaboratory in late June and early July were put in rearing cages con- 
taining small branches of fruit and leaves and also fruit juices and 
sugar for food. The first eggs were deposited July 3. Some of the 
moths died before depositing eggs. On June 28, 1909, while looking 
after spraying operations in the field, frequent searches were made 
in the unsprayed block, but no eggs were found. During another 
search on July 7 among these trees many eggs were found and 5 
larve just hatched, none of which had entered fruit, were found dur- 
ing the forenoon. Eggs were being deposited in large numbers in 
rearing cages July 8 to 10. 
Incubation period.—The time required for incubation was less than 
half that required for the first-brood eggs. In cages this varied from 
7+ to 94 days, and averaged 8} days. The weather at this time was 
usually warm throughout the day with comparatively cool nights. 
In Table VIII are recorded incubation periods for several groups of 
eggs deposited between July 3 and 29. It will be noticed that eggs 
deposited July 10, 11, 26, and 28 required shorter time for incubation 
than others. Both of these periods were followed by 3 to 4 days of 
very warm weather. 
TaBLE VIII.—IJncubation periods of second-brood eggs, Walnut Creek, Cal., 1909. 
Date of— | Date of— 
So} Letsaroye! fata . Period 
Observa- | Number : of in- Observa- | Number | p of in- 
, P coon | HSE dep-| Hatch- | és scoe | HSE dep-| Hatch- 
tion No. | of eggs. Ration ing of | cube: tion No. of eggs. osition ing of canes 
(night). eggs. eres (night). eggs. on. 
| Days. | | Days. 
i eopeamane 3 July 3) July 12 Sh tl One seen 45 | July 15 | July 24 8 
Pee SGOGOC EL 4 6 16 Oui ie cries i= 35 16 25 8 
Oirerseehelai= 4 7 16 roth | hela eeenee 20 17 26 8 
CASSIS 10 uf 16 S| Woe seaSsees 12 20 | 29 8 
Ree ames oe 15 8 17 Sol] Tee eee 70 24) Aug. 2 | 8 
Ge setseease 19 10 18 Hea alts are neers 75 26 3 | 7 
Tee, ee 15 is 19 TANGER okt oe 60 28 5 7 
Soescctee-e 14 12 22 Chl uiSosce sece 40 29 6 8 
Qeec see tebe | 11 13 23 OF || Saree sessee | 9] Aug. 1 12 10 
Incubation period: Days. 
PGC) ps Senge a ae cod BS noe HOOD OSCE S NG PCO OES Sa AUP SS CR MANT EOS SHRAAgOO Sec D Abe soca actos sc 8.05 
IW Eb Grint eyes eos Soc oa ae ere PERE AC DOSE BOTED SO - noc aes Em qe ROBE AC UES coc enod Sooshseoscetss 10. 00 
Minimum 2.1. bss see aac loci Mine Gee steiale ja arelolesnisla side lelc bier. shiw ole coc ee sie Uk Sar aT Tee eotet oleae 7.00 
