55 



At various times records have been made of finding single moths 

 late in the season, in October. The presence of these moths can be 

 easily accounted for by the fact that the larvae probably got into some 

 place where the general outside temperature had no effect on them, 

 and increased temperature caused transformation. 



EVIDENCES OF A THIRD GENERATION. 



It is often found that in September a large number of the fruits 

 have been entered by very young insects, and it is also found that in 

 some localities these injuries extend into October. This has given rise 

 to the belief that there is a third generation present; and not having 

 definite records in regard to the life history of the codling moth, many 

 fruit growers have come to the conclusion that there are three gener- 

 ations, and some have even gone so far as to say that there is a par- 

 tial fourth generation. Many entomologists have taken these state- 

 ments from the fruit growers, and not having given as complete study 

 to the subject as was possible, have published the conclusion that three 

 generations were present. The writer has collected all of the publi- 

 cations in which three generations were either indicated or given as 

 occurring, and has, with the greatest of care, studied the observations 

 upon which the conclusions were based. Many entomologists have 

 su))mitted original notes or copies of the notes from which their con- 

 clusions were drawn. After carefully stud^nng all these records and 

 published accounts the conclusion was reached that there were only 

 two publications in which any substantial evidence is given as to the 

 existence of a third generation of the codling moth. Professor Cock- 

 erell, in a bulletin of the New Mexico Experiment Station, concludes 

 that there are three generations and a partial fourth. Professor Cock- 

 erell relied mainly upon observations, and checked these oi)servations 

 by breeding experiments in only a few instances. The observations, 

 while of value, give the conditions in the orchard at irregular inter- 

 vals, and then only for a very short period of time. Many erroneous 

 conclusions w^ere drawn from these observations. For instance, the 

 finding of an empty pupa case on June 20 was considered an evi- 

 dence that the moths of the first generation had emerged. In view of 

 the fact that Professor Gillette finds that the extreme period of emer- 

 gence of the moths in the spring is 69 days at Fort Collins, and that 

 Professor Slingerland found moth in New York as late as June 22, we 

 see that there is the greatest probability that these moths were the 

 latter part of the hibernating genei'ation, instead of the first part of 

 the first generation. The finding of wormy apples on July 3 was con- 

 sidered as the beginning of the second generation entering the fruit. 

 On August 12 small larvix? in fruit were considered to be the beginning 

 of the third generation. Anyone familiar with the conditions of 

 Western orchards knows that small larvae entering the fruit can be 



