THE GRAIN BUG. 



13 



Table II. — Duration of nymphal instars of Chlorochroa sayi in period from 

 July 5 to August 18, 1916. 



i 



<0 





"3 



1 

 .9 



■«« 



_^ c 







^ji 



^i 



^5 



OS 



2^- 







1 



e 



11 



11 



si 



§3 



3° 



11 



"C to 



5^ ' 



S3 O 



il 



f^ 



^ 



f^ 



f^ 



w 



m 



H 



H 



f^ 



f^ 



Pm"^ 



f^ 



tH 









Days. 





Days. 





Days. 





Days. 





Days. 



Days. 



1-... 



July 5 



July 10 



5 



July 19 



9 



July 24 



5 



Aug. 1 



8 



Aug. 16 



15 



42 



2.... 



...do... 



...do.... 



5 



...do.... 



9 



...do.... 



5 



...do... 



8 



...do.... 



15 



42 



3.... 



...do... 



...do.... 



6 



...do.... 



9 



July 25 



6 



...do... 



7 



Aug. 17 



16 



43 



4.... 



...do... 



...do.... 



5 



July 17 



7 



July 24 



7 



...do... 



8 



Aug. 16 



15 



42 



5.... 



...do... 



...do.... 



6 



...do.... 



7 



...do.... 



7 



...do... 



8 



Aug. 18 



17 



44 



6.,.. 



...do... 



...do.... 



5 



July 18 



8 



July 25 



7 



Aug. 3 



9 



Aug. 17 



14 



43 



7.... 



...do... 



...do.... 



S 



July 19 



9 



...do.... 



6 



Aug. 1 



7 



Aug. 16 



15 



42 



8.... 



...do... 



...do.... 



5 



July 18 



8 



...do.... 



7 



Aug. 2 



8 



Aug. 17 



15 



43 



9.... 



...do... 



...do.... 



5 



July 19 



9 



...do.... 



6 



Aug. 3 



9 



...do.... 



14 



43 



10.... 



...do... 



...do.... 



5 



July 18 



8 



...do.... 



7 



...do... 



9 



...do.... 



14 



43 



11.... 



...do... 



...do.... 



5 



...do.... 



8 



...do.... 



7 



Aug 2 



8 



...do.... 



15 



43 



12.... 



...do... 



...do.... 



5 



...do.... 



8 



...do.... 



7 



...do... 



8 



Aug. 18 



16 



44 



13.... 



...do... 



...do.... 



5 



...do.... 



8 



July 24 



6 



Aug. 1 



8 



Aug. 17 



16 



43 



14.... 



...do... 



...do.... 



5 



...do.... 



8 



July 25 



7 



Aug. 3 



9 



Aug. 16 



13 



42 



15.... 



...do... 



...do.... 



5 



...do.... 



8 



July 24 



6 



...do... 



10 



Aug. 17 



14 



43 



16.... 



...do... 



...do.... 



5 



...do.... 



8 



...do.... 



6 



Aug. 1 



8 



Aug. 16 



15 



42 



17.... 



...do... 



Average. 



...do.... 



5 



...do.... 



8 



July 25 



7 



Aug. 2 



8 



Aug. 17 



15 



43 



, 



S 



8.2 



6.4 



8.2 



14.9 



42.7 





. 











Later in the season during a period of cooler weather, from August 

 10 to September 30, 1916, the duration of the nymphal stages of 25 

 nymphs averaged 7 days for the first instar, 14 days for the second 

 instar, and 18 days for the third instar. (See Table III.) This 

 series of experiments was discontinued on October 3. 



Table III. — Duration of nymphal instars of Chlorochroa sayi in period from 

 Aug. 16 to Sept. 30, 1916.^ 



No. 



Nymph 

 hatched. 



First 

 molt. 



First 

 instar. 



Second 

 molt. 



Second 

 instar. 



Third 

 molt. 



Third 

 instar. 



1 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 



10 

 11 

 12 

 13 

 14 

 15 

 16 

 17 

 18 

 19 

 20 

 21 

 22 

 23 

 24 

 25 



Aug. 16 

 ....do 



Aug. 23 

 ....do 



Days. 

 7 



7 



7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 

 7 



Sept. 7 

 Sept. 6 

 Sept. 7 



....do 



Sept. 6 

 Sept. 5 

 Sept. 7 

 Sept. 8 

 Sept. 6 

 Sept. 5 

 Sept. 7 



....do 



Sept. 5 

 Sept. 7 



....do 



Sept. 6 



....do 



Sept. 7 



....do 



....do 



Sept. 6 

 Sept. 7 

 Sept. 6 



..-.do 



Sept. 8 



Days. 

 15 

 14 

 15 

 15 

 14 

 13 

 15 

 16 

 14 

 13 

 15 

 15 

 13 

 15 

 15 

 14 

 14 

 15 

 15 

 15 

 14 

 15 

 14 

 14 

 16 



Sept. 22 

 Sept. 23 

 Sept. 27 

 Sept. 23 



....do 



Sept. 22 

 Sept. 26 



....do 



Sept. 24 

 Sept. 23 

 Sept. 28 

 Sept. 26 

 Sept. 25 

 Sept. 26 

 Sept. 30 

 Sept. 24 

 Sept. 26 

 Sept. 25 

 Sept. 22 

 Sept. 25 

 Sept. 23 

 Sept. 22 

 Sept. 25 

 Sept. 22 

 Sept. 27 



Days. 

 15 

 17 

 20 

 16 

 17 

 17 

 19 

 18 

 18 

 18 

 21 

 19 

 20 

 19 

 23 

 18 

 20 

 18 

 15 

 18 

 17 

 15 

 19 

 16 

 19 



....do 



....do 



....do 



....do 



do 1 - -do 



do 



....do 



do 



do 



....do 



....do 



. ..do 



do 



do 



....do 



. ..do 



do 



do 



do 



....do 



do 



....do 



do 



....do 



....do 



do 



....do 



....do 



....do 



do 



do 



....do 



....do 



do 



do 



....do 



do 



....do 



do 



....do 



....do 



do 



do 



....do 



....do 





A 



verages 



7 





14.5 





18.08 











1 Discontinued Oct. 3, 1916. 



