14 BULLETIN 539; U. S. DEPARTMENT OF AGRICULTURE. 



LENGTH OF INCUBATION PERIOD. 



From Tables I and II it will be seen that the egg stage varies from 

 three days in the summer time to five days in early fall, being influ- 

 enced greatly by temperature conditions. In late fall, eggs were 

 obtained that required from six to eight day's to hatch. 



Table III. — Number of eggs deposited by 1 female of Elasmopalpus lignosellus in 

 1 day and during life, at Columbia, S. C, 1915. 



Cage 15-1112. 



Cage 15-1113. 



Cage 15-1114. 



Date of oviposition. 



Number 

 of eggs. 



Date of ovipo- 

 sition. 



Number 

 of eggs. 



Date of ovipo- 

 sition. 



Number 

 of eggs. 





73 



11 



73 



61 



27 



39 



27 



15 



6 



4 



6 



Sept. 2-3 



Sept. 4 



Sept. 5 



Sept. 6 



Sept. 8 



Sept.9 



Sept. (?) 



Sept. 10 

 Sept. 11 



25 



36 



11 



5 



9 



7 



20 



9 



12 



Aug. 31 

 Sept. 1 



Sept. 4-5 

 Sept. (?) 



Sept. 9 



Sept. 10 

 Sept. 11 

 Sept. 12 



15 



31 



38 



19 



60 



22 



3 



3 



1 





June 17 







June 22 



June 23 









June 28 



Total 



342 

 24.43 



134 

 (?) 



192 

 (?) 



Average per day.. . 











Cage 15-1115. 



Cage 15-1116. 



Cage 15-1117. 



Date of oviposition. 



Number 

 of eggs. 



Date of ovipo- 

 sition. 



Number 

 of eggs. 



Date of ovipo- 

 sition. 



Number 

 of eggs. 



Sept. 10 



53 



56 



38 



34 



1 



9 



2 



4 



Sept. 8 



Sept.9 



Sept. 10 

 Sept. 11. 

 Sept. 12 

 Sept. 14 



56 

 35 

 34 

 33 



28 

 8 



Sept. 13 

 Sept. 14 

 Sept. 15 



24 

 55 

 12 



Sept. 11 



Sept. 12 



Sept. 13 



Sept. 14 



Sept. 15 



Sept. 16 



Sept. 17 



Total 



197 

 24.63 



194 

 27.71 



91 

 30.30 



Average per day.. . 











NUMBER OF EGGS DEPOSITED BY ONE INDIVIDUAL. 



The number of eggs deposited by one individual under laboratory 

 conditions varies (as will be seen by referring to Table III) from 91 to 

 342, with an average of 190. The small number deposited in Cage 

 15-1117 was probably due to premature death of the female. 



The number of eggs deposited by one individual in any one day 

 varies from 1 to 73. The daily average computed from the daily 

 average of the four cages in Table III is about 26.77 eggs. 



In two other experiments conducted in July, 1914, 188 eggs were 

 obtained in one cage and 311 eggs in the other. 



