28 



DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



apparently bored down the twigs until they encountered wood too 

 hard for them to chew, when they left the burrows and were lost. 

 In the laboratory four larvae just hatched were put on foliage 

 May 7. The ends of the twigs were stuck into a bottle of water, 

 cotton was stuffed around the neck of the bottle, and the whole put 

 under a bell jar. Two larvae were working May 12. On May 23 

 one larva was still feeding. It had begun work on a leaf, then it 

 bored into the midrib and through the petiole into the end of the 

 twig. The larva was transferred to a fresh twig, and when again 

 examined, May 29, had burrowed for a distance of 1} inches. Then 

 it had left the burrow, and forcing its w T ay through the cotton at the 

 neck of the bottle had drowned itself therein. It had reached a 

 length of 9.5 millimeters and appeared to have passed the fifth molt. 



LARV.E IN PEACHES. 



Two peaches containing codling-moth larvae were collected in the 

 orchard, on trees adjoining an apple orchard. Both peaches ripened 

 several days before the larvae left them. One larva issued July 28 

 from a peach collected July 10. The adult emerged August 10. 

 Another peach collected July 29 gave out a larva on August 2, from 

 which the adult emerged August 16. 



NUMEROUS LARV^ IN ONE APPLE. 



Throughout the season, and also in 1907, it was noticed that when 

 large numbers of young larvae were allowed to enter a single apple 

 at the same time, only a few survived. If larvae being reared from 

 eggs laid in cages were not transferred to separate fruits within three 

 to five days after hatching, or before their burrows reached the core, 

 onlv a small proportion of the number entering could be accounted 

 for.^ 



Some third-brood larvae entering fruit in cages were left undis- 

 turbed, the apples being kept in jars out of doors. The results, 

 given in Table XXXIV, show that more than one larva is not likely 

 to reach maturity in a single fruit at the same time. 



Table XXXIV. — Record of maturing larvse from 4 apples, each in 



time by numerous larvse. 



at the same 



Eggs 

 hatched. 



Number 



of larvse 



entering 



apple. 



Larvae formed 

 cocoons. 



Number 

 of larvse 

 maturing. 



Date. 



Number. 



Aug. 14.. 



Do 



Sept. 14.. 



18 



11 



18 

 8 



Sept 5 

 fSept. 5; 

 1 spun co- 

 | coon in 

 I fruit, 



Oct. 20 

 ...do.... 



1 



h 



1 



} 2 



1 

 1 



