14 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



Mr. G. W. Whitman and Dr. F. W. Bancroft, of Concord, Cal., and Mr. 

 G. W. Langdon, of Suisun, Cal., for their hearty cooperation in fur- 

 nishing labor and material to help in the experiments. 



LIFE-HISTORY NOTES ON THE CODLING MOTH IN CALIFORNIA. 



OVERWINTERING LARV^. 



Many codling-moth larvae could be found in the orchards and 

 around the packing sheds during the winter of 1908-9, but all obser- 

 vations go to show that a comparatively small percentage of the larvae 

 maturing in fruit the previous season went through the winter suc- 

 cessfully. This may be partly explained by the fact that the pears 

 are picked and taken to the sheds while a large percentage of the 

 second-brood larvae is still in the fruit. Many of these larvae are 

 destroyed or taken so far away that the adults fail to get back to the 

 trees in spring. However, larvae were frequently found under old 

 burlap bands left on trees, and in the cracks and crevices and under 

 rough bark. 



SPRING BROOD OF PUP^. 



The earliest date of actual pupation was not observed, but'the first 

 pupa was found on March 11, 1909. In removing the bands from 

 seven pear trees in the Ygnacio Valley near Walnut Creek, 8 larvae 

 and 2 pupae were found. The next day, March 12, 32 larvae and 6 

 pupae were found in the same orchard. March 22, another search 

 showed 7 larvae and 6 pupae. On March 23, while looking through 

 some boxes at a vinegar factory, 16 larvae and 9 pupae were found. 

 These boxes had been kept under shelter during winter. One 

 freshly shed pupal skin was found in the corner of a box, indicating 

 that the first larva had perhaps pupated in February. On March 

 27, 14 pupae and 1 pupal skin but no larvae were found under bands. 



The larvae collected on these dates, together with a small sending 

 from San Jose, were kept separately in vials, with bits of paper and 

 cloth, for pupal records. Records kept at San Jose showed the first 

 pupa on February 20. (See Table III.) 



During February, 1910, about 300 larvae secured from banded trees 

 the previous season were put in vials for individual pupation records. 

 Four of these larvae had pupated by March 12. Of the 118 which 

 produced adults in spring, 95 had pupated by March 31 and all had 

 pupated April 10. The dates of pupation are given in Table II. 

 Practically all larvae under observation out of doors at the laboratory 

 at Walnut Creek in 1909 and 1910 and San Jose in 1909 had pupated 

 by the last of April, giving some two months during which larvae 

 transformed to pupae. From the appearance of the first pupa, Feb- 

 ruary 20, till the emergence of the last moths from overwintering 



