BIONOMICS OF THE CHINCH BUG. 5 



Females and males, taken in copula in the field very early in 

 spring, were placed in test tubes and counts made of the number of 

 eggs laid. Data relating to four of these cages are given in Table I. 

 The largest number of eggs deposited in any one of the four cages 

 was 119, in cage 20-51. The smallest number, 51, was obtained in 

 cage 20-53. The average number deposited by one female, based on 

 the four individuals, is 85.25 eggs. Oviposition extended over a 

 period of 56 egg-laying days in cage 20-50, and only 41 days in cage 

 20-51, although more eggs were deposited in the former cage than in 

 the latter. 



Although the individuals were collected from the field, there does 

 not seem to be much doubt that the females had begun to oviposit 

 before they were captured, since they were taken at the time of their 

 migration and shortly afterwards, and at the time when they were 

 copulating in great numbers. 



Table 1. — Records of daily and total egg production of four individuals of 

 Blissus leucopterus, Columbia, S. C, 1920. 



Cage No. 20-50. 



Date of oviposi- 

 tion. 



Num- 

 ber 

 of 

 eggs. 



May 11 



1 



May 12-26 



May27 



2 



May 28-31 





2 

 1 

 2 

 3 

 1 

 3 

 2 

 4 

 6 



June 2 



June 3 







June 6-7 



June 8-9 



June 10 



June 11 



June 19 ... 



June 13-14 



14 

 2 

 7 



10 

 3 



12 

 7 

 2 

 3 



June 16 



June 17-18 



June 19 



June 20-21 



June 22-23 



June 24 



June 25-26 



June 27-29 



June 30 



1 



7 



July 1-6 





Total 



95 



Cage No. 20-51. 



Date of oviposi- 

 tion. 



May 8 



May 9-25. . 



May 26 



May 27-28. 



May 29 



May 30-31. 



June 1 



June 2 



June 3 . . . . 

 June 4 . . . . 



June 5 



June 6-7 . . . 

 June 8-9.. . 



June 10 



June 11 . . . 

 June 12 . . . 

 June 13-14. 

 June 15 . . . 

 June 16 ... . 

 June 17-18. 



Total. 



Num- 

 ber 

 of 



119 



Cage No. 20-53. 



Date of oviposi- 

 tion. 



May 9 



May 10 



May 11.... 



May 12 



May 13. . . . 

 May 14.... 

 May 15-20. 

 May 21.... 

 May 22-24. 

 May 25.... 

 May 26.... 

 May 27.... 



May 28 



May 29. . . . 



Total. 



Num. 

 ber 

 of 



Cage No. 20-55. 



Date of oviposi- 

 tion. 



May 9 



May 10 



May 11 



May 12 



May 13 



May 14-24 



May25 



May 26 



May 27 



May 28 



May 29 



May 30-31 



June 1 



June2 



June 3 



June 4 



June 5 — Female 

 dead; dissected. 



Total. 



Num- 

 ber 

 of 



eggs. 



75 



LENGTH OF THE EGG STAGE. 



The length of the incubation period is governed primarily by pre- 

 vailing temperature. During early spring it may be slightly more 

 than a month and during midsummer a trifle more than a week. In 

 the laboratory at Columbia, S. C, a record on the incubation period 



