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were found, tlioiigh only two weeks had elapsed since tlie preceding 

 examination, showing that in this time sixteen of the worms had entered 

 the band, gone through with their transformations and emerged in the 

 winged form, and therefore that in order to capture every worm that en- 

 ters the bands, the examinations must be made oftener than every two 

 weeks, say every ten or twelve days. 



We have already stated that, as a general rule, the second brood of 

 worms do not change to moths till the following spring, and therefore 

 that it is unnecessary to examine the bands after the first brood have 

 ceased to emerge, until we examine them once for all late in the season. 

 What, then, is the dividing time between the two broods ? This, like 

 most other questions in natural history, can not be answered by draw- 

 ing a straight line. The two broods overlap each other to a very limited^ 

 extent, but not sufiQciently to invalidate the adoption of general practical 

 rules. If we refer back to tables Nos. 4 and 5, we shall see that at these 

 examinations only unchanged larv?e were found, from which we infer that 

 all the worms which entered the bands after the 25th of August belonged 

 to the second brood. And in the preceding examination, embracing 

 the period between the 11th and the 25th of August, only five out of 

 forty-six worms had changed to pupa?. Judging from these tables we 

 conclude that in this latitude the dividing time between the two broods 

 is about the middle of August, and therefore that it is unnecessary to ex- 

 amine the bands after this date, until the final examination. If we put 

 the time of the first examination on the tenth of July, and the last but 

 one on the fifteenth of August, it will require three intermediate ex- 

 aminations at intervals of twelve days, making four summer and one 

 fall or winter examination, or five in all. 



By the collation of these dates we may adopt a general rule which 

 will answer for all latitudes and seasons. Supposing the bands to have 

 been applied at any convenient time within a mouth after the blossoming 

 of the apple trees, then, allowing one week after the falling of the apple 

 blossoms for the laying and hatching of the earliest eggs, thirty days 

 for the growth of the larva and twelve days for the duration of the 

 pupa state, it follows that the moths will not begin to escape from the 

 bands till the expiration of seven weeks after the falling of the blossoms, 

 and therefore that the first examination of the bands need not be made 

 till a day or too previous to the expiration of this time. After this they 

 must be examined three times at intervals of twelve days, and once 

 more at the end of the season. 



We may here add that these methods of entrapping the Codling- worms 

 are much more eflficaciousi upon young and smooth trees than upon old 

 and rough ones, for the reason that ujion the latter many of those worms, 

 which leave the apples on the tree, spin up under the scales on the 



