248 



THE CODLING MOTH DOUBLE-BROODED. 



By C. L. Marlatt. 



The double-broodedness of the codling moth has been called in ques- 

 tion by Prof. J. 13. Smith as a result of experience during the last three 

 seasons at New Brunswick, N. J., in which larvae constituting the 

 supposed first brood and maturing early in July remained in every 

 instance unchanged in their cocoons until the next spring. ( Ent. News, 

 vol. V, p. 284.) Prof. Smith does not deny the possible occurrence of 

 the second brood, which has been so generally accepted by nearly all 

 later writers on the subject, but considers, and perhaps justly, that 

 this experience leaves room for doubt, and asks for positive observations. 



In the earliest American accounts, viz, those of Harris (Ins. Inj. to 

 Veg., Flint Ed., p. 484), and Fitch (Third Report, No. 48) a single brood 

 in general is somewhat indefinitely indicated, both of these writers 

 apparently following or quoting the statements of Europeans rather 

 than advancing any personal experience. 



That the insect is single-brooded in northern Europe, including 

 northern and central Grermany, is asserted by Grerman authors; and 

 this is also true of England (Westwood, Gard. Mag., 1838, p. 237), 

 while in the latitude of Vienna (48°) (Schmidtberger) and in France 

 (Reaumur, Memoires des Ins. ii, p. 499) it is double-brooded. West- 

 wood and Reaumur give actual breeding records. The fact of single- 

 broodedness in parts" of Europe is alluded to by Prof. Riley (Third Re- 

 port, p. 102) and by Mr. Howard (Ann. Rep. Dept. Agric, 1887, p. 90). 



On looking over the later x>ublislied records in this country of actual 

 observations, the occurrence normally of a second or summer brood of 

 moths throughout the United States, with the possible exception of 

 the northeast Atlantic region, can not be doubted. That there are 

 two broods in the Middle States is shown by the records given by Prof. 

 Riley in several of his Missouri reports. He states in his Fourth 

 Report (p. 22) that he has bred thetn nearly every year for ten years 

 in different localities, and records for St. Louis (Sixth Report, p. 11) 

 the earliest mature larva, June 23, and the earliest moth July 8. 



Noteworthy among these records is the account by Le Baron, who 

 made some very careful studies, and convinced himself of the double- 

 broodedness of the insect throughout Illinois and the West, with the 

 possibility of a third brood for the South. In the latitude of Chicago 

 he fonnd the great majority of the summer brood of moths to emerge 

 in the last week of July and the first of August. I will quote merely 

 the results of his examination of bands put on trees July 10, which 

 shows that the larviie transformed to pupa; and issued as moths generally 

 throughout July and most of August. (See Le Baron's Third Report, 

 p. 175.) 



