A PEST OF CURED TOBACCO, EPHESTIA ELTJTELLA HUBNER 7 

 RATE OF DEVELOPMENT ON TOBACCO 3 



Table 1 contains data showing the developmental periods of 30 

 individuals of Ephestia elutella that hatched during June and July, 

 1931, and Table 2 contains similar data for 30 individuals that hatched 

 during August. 



Table 1. — Data on development of Ephestia elutella from eggs laid on flue-cured 

 tobacco in the laboratory at Richmond, Va., during June and July, 1931 



Rearing No. 



Date egg 

 was laid 



1 



June 23 



2 



3 



5 



...do 



.-do 



...do 



...do 



6. 



...do 



7 



8-. 



...do 



June 24 



9 



10 



11 



12 



—do 



—do 



—do 



...do 



13 



June 25 



14 



15 



16 



17 



18 



...do 



—do 



—do 



—do 



June 26 



19 



June 27 



20 



June 28 



21 - 



July 7 



22 



23 



24 



—do 



...do 



—do 



July 8 



—do 



...do 



July 10 



26 



27 



28- - - -- 



29 



July 17 



30 



July 18 



Average. 



Incuba- 

 tion 

 period 



Larval 



Pupal 



period 



period 



Days 



Days 



Days 



6 



36 



9 







35 



9 



6 



36 



9 



5 



41 



11 



5 



47 



13 



6 



42 



10 



7 



61 



9 



5 



31 



9 



5 



37 



11 



5 



45 



11 



5 



44 



14 



5 



31 



9 



5 



33 



7 



5 



39 



11 



5 



49 



11 



5 



55 



10 



5 



47 



14 



4 



41 



8 



5 



43 



14 



5 



53 



9 



3 



42 



12 



4 



33 



13 



4 



38 



14 



4 



53 



9 



4 



29 



14 



4 



38 



15 



4 



48 



10 



4 



38 



13 



5 



66 



12 



4 



72 



19 



4.8 



43.4 



11.3 



Date 



adult 



emerged 



Aug. 13 

 Aug. 11 

 Aug. 13 

 Aug. 19 

 Aug. 27 

 Aug. 20 

 Sept. 8 

 Aug. 8 

 Aug. 16 

 Aug. 24 

 Aug. 26 

 Aug. 8 

 Aug. 9 

 Aug. 19 

 Aug. 29 

 Sept. 3 

 Aug. 30 

 Aug. 18 

 Aug. 28 

 Sept. 3 

 Sept. 2 

 Aug. 26 

 Sept. 1 

 Sept. 11 

 Aug. 24 

 Sept. 3 

 Sept. 8 

 Sept. 3 

 Oct. 8 

 Oct. 21 



Sex 



Female. 

 Male... 

 ... do— . 

 Female- 

 Male.. . 

 Femaie. 

 ... do— . 

 ...do— . 

 ... do— 

 — do— 

 ... do— . 

 Male... 

 Female- 

 Male... 

 Female. 

 ... do— 

 — do— . 

 ... do.— 

 Male— 

 Female. 

 ... do— . 

 Male.. - 

 ... do— 

 — do— 

 ... do... . 

 ... do— 

 ... do— 

 ... do... . 

 Female- 

 Male— 



Period from egg to adult 



Dura- 

 tion 



Days 

 51 

 49 

 51 

 57 

 65 

 58 

 77 

 45 

 53 

 61 

 63 

 45 

 45 

 55 

 65 

 70 

 66 

 53 

 62 

 67 

 57 

 50 

 56 

 66 

 47 

 57 

 62 

 55 

 83 

 95 



Temperature « 



Mean 

 maxi- 

 mum 



3 F. 

 89.0 

 89.8 

 89.0 

 89.0 

 87.4 

 79.8 

 80.3 

 89.8 

 88.6 

 87.5 

 87.4 

 89.8 

 90. 1 

 87.4 

 86.2 

 86.2 

 86.1 

 87.5 

 86.3 

 86.2 

 85.7 

 85.8 

 85.7 

 85.6 

 85.8 

 85.7 

 85.4 

 85.5 

 85.9 

 83.8 



Mean 

 mini- 

 mum 



3 F. 

 69.9 

 70.1 



69.0 

 69.8 

 68.2 

 70.3 

 69.9 

 69.4 

 69.1 

 70.3 

 70.4 

 63.6 

 67.8 

 67.6 

 67.8 

 68.0 

 68.1 

 67.8 

 67.4 

 67.9 

 67.5 

 66.9 

 68.2 

 67.4 

 66.4 

 67.2 

 65.1 

 62.8 



Mean 



F. 



79.4 



79.9 



79.4 



79.4 



78.2 



74.8 



74.2 



80.0 



79.2 



78.4 



78.2 



80.0 



80.2 



75.5 



77.0 



76.9 



76.9 



77.7 



77.2 



77.0 



76.5 



76.8 



76.6 



76.2 



77.0 



76.5 



75.9 



76.3 



75.5 



73.3 



o The temperatures recorded in this table were obtained from the records of the United States Weather 

 Bureau, Richmond, Va. 



3 A. W. Green, field assistant at the tobacco insect laboratory, June to September, 1931, assisted with 

 some of the life-history studies recorded in this circular. 



