64 



Journal of Agricultural Research 



Vol. XIII. No. I 



sible to tell when one generation had developed fully or when another 

 had begun work, except by rearing the insects through the season under 

 conditions as nearly natural as possible. 



Table I shows the dates of the beginning of severe injury to peaches 

 by each brood of larvae, the percentages of fruit injured as shown by 

 counts in definite periods throughout the summer, and a few varieties 

 of peaches ripening in each period. 



Table I. — Dates of injury to peaches by respective broods of larvce of the oriental peach 

 moth, Arlington Farm, Va., igij 



Date of beginning of severe injury. 



Percentage of peaches injured 

 in period f rom^ 



Common varieties of peaches 

 ripening in periods named 

 in column 2. 



By first generation, May 31. 

 By second generation, July 6. 



By third generation, July 28. 



By fourth generation, Aug. 30. 

 By fifth generation, Oct. 7. 



May 3 1 to June 30 . . . . o . 

 July I to July 15 .. .2.5. 



July i6to July 31 3. 



Aug. I to Aug. 15 ... if 



Aug. 16 to Aug. 31. .28.2. 



Sept. I to Sept. 16 ... 53 . 



Sept. 17 to Oct. 20, no 



count made. 

 All fruit harvested 



Greensboro. 

 /Greensboro. 

 IWaddell. 

 fCarman. 

 IHiley. 

 rChampion. 



Early Crawford. 



Bell. 



Old Mixon Free. 



Reeves. 



Elberta. 



Late Crawford. 



Chairs. 

 fSmock. 

 \Stump. 

 fSalway. 

 \Bilyeu. 



INSECTS LIKELY TO BE CONFUSED WITH THE ORIENTAL PEACH MOTH 



There are several insects which may be confused with Laspeyresia 

 molesta in the larva stage, either because of a close resemblance or because 

 of a similarity in the injuries which they cause. The more common 

 of these are the codling moth, Laspeyresia pomonella Linnaeus; the lesser 

 apple worm, L. prunivora Walsh; the peach twig borer, Anarsia linea- 

 tella Zeller; and Laspeyresia pyricolana Murtfeldt. 



L. pomonella is likely to be mistaken for L. molesta in the fruit of the 

 apple, pear, and quince, but close examination will show several points 

 of difference in the mature larvae. The following characters serve to 

 separate the larvae of the two species: On L. pomonella (PI. 8,G) the 

 anal fork is absent; a scobinated pad is present extending across the 

 anal proleg just in front of the crochets; the crochets on abdominal 

 prolegs are 23 to 38 in number. On L. molesta (PI. 8, F) the anal fork 

 is present, situated just below the anal plate and above and behind 

 the anal prolegs; the scobinated pad is absent; the crochets are 31 to 

 46 in number. The full-grown larva of L. molesta is smaller than that 

 of L. pomonella. 



