72 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



SEASONAL-HISTORY STUDIES OF 1909. 

 SOURCE OF REARING MATERIAL. 



The main portion of the rearing material used in the spring of 1909 

 was collected during the previous summer and fall from banded apple 

 trees; the rest— a small fraction — constituted reared specimens from 

 experiments of the previous year. The larva? intended for pupal 

 records were allowed to make their cocoons between narrow strips of 

 wood (fig. 18), where their transformation could be readily observed 

 without greatly altering their conditions, while those for emergence 

 records of the moths cocooned in masses of old bark of apple trees. 

 During the winter the material was kept in a medium-sized glass jar, 

 covered with thin cloth, and was thus left undisturbed in an open 

 shelter (see Plate IX) until the following spring. 



Fig. 18.— Device consisting of strips of wood held together by rubber bands used in obtaining pupal 

 records of the codling moth ( Carpocapsa pomonella). Reduced. (Original.) 



The rearing material for the following emergence of moths, or 

 first-brood moths, was mainly from that used in taking the band 

 records of 1909, and, to a small extent, from reared specimens. There 

 is a special value in the use of band-collected larva? in the rearing of 

 the codling moth, in that these have up to the time of transforming 

 developed normally in the field and the resulting adults show thus 

 both the normal time of emergence and the relative occurrence in the 

 field. 



OVERWINTERING LARVAE. 



The overwintering larva? of the codling moth in the vicinity of 

 North East, Pa., are partly of the first and partly of the second broods. 

 As is more fully considered on page 84, a portion of the first-brood 

 larvae, unlike the rest, hibernate — as do normally all larva? of the 

 second brood — and complete their life cycle the following spring. 



