160 



DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



Table L, a summary of Table XLIX, shows the average maximum 

 and minimum time spent by the second-brood larvae in feeding. 



Table L. — Feeding period of second-brood larvse: Summary of Table XLIX. 



Observations. 



Days in 

 the fruit. 



Average 



58.15 



79 



43 



Maximum 



Minimum 



Time of leaving the fruit for wintering. — Table XLIX shows that 

 the date the earliest larvse left the fruit was October 19, but as 

 these larvse were not from the earliest eggs deposited and the earliest 

 moths did not oviposit in confinement the band record will show 

 when most of the larvae cocooned for the winter. The band record 

 for 1911 shows that after August 31 second-brood larvae were un- 

 doubtedly hibernating and that they reached their maximum from 

 September 28 to October 5. The earliest second-brood larvae prob- 

 ably cocooned the latter part of August and since half-grown larvae 

 were found in apples on the tree as late as November 30, it is possible 

 that the last stragglers did not cocoon until some time during Decem- 

 ber, 1911, or January, 1912. 



NATURAL ENEMIES OF THE CODLING MOTH. 



Parasitic insects. — The egg parasite Trichogramma pretiosa Kiley 

 may be regarded as a factor in the control of the codling moth in the 

 Santa Clara Valley. In 1909 eggs of the host were collected to 

 obtain records on the parasites. A large number of the Tricho- 

 gramma issued, but as there was no record of the time when the eggs 

 were laid by the moths or parasitized by the chalcidid, the life cycle of 

 the parasite was not determined. In 1910 the Trichogramma was 

 very abundant, so much so that in the life-history work on the codling 

 moth the jelly glasses in the insect ary containing the eggs had to be 

 carefully covered to keep out the parasite. In this year a record 

 was kept relative to the life cycle of the parasite. 



Table LI gives notes on the life history of eight parasites. 



Table L-I. — Life of Trichogramma pretiosa in codling-moth eggs. 



Date eggs 

 laid. 



Date para- 

 sitism 

 observed. 



Date para- 

 site 

 emerged. 



Days from 

 deposition 

 of eggs to 

 hatching 

 of parasite. 



July 24 

 Do..... 



July 27 

 Do 



July 28 

 Do 



Aug. 5 . 

 ...do 



Aug. 10 

 ...do 



Aug. 5 

 ... do 



Aug. 19 

 Aug. 20 

 Aug. 23 

 Aug. 24 

 Aug. 19 

 ... do 



26 

 27 

 27 

 28 

 22 

 22 

 21 

 20 



Aug. 1 

 Aug. 2 



Aug. 10 

 ...do 



Aug. 22 

 ...do 



