THE GEAlisr BIJG. 



15 



and oviposition was 41 days. This is probably longer than the period 

 required under field conditions, judging from the number of genera- 

 tions each year. The females maturing late in the season do not ovi- 

 posit until the following spring. 



PEOPOKTION OF SEXES. 



Under field conditions the females of Chlorochroa sayi are slightly 

 more abandant than the males. In a total of 564 adults, collected 

 from various habitats throughout the active season, 313 were females 

 and 251 were males. (See Table IV.) 



Table IV. — Proportion of sexes of Clilorochroa sayi in different liabitats tlirougJi- 



out the active season. 



Date. 



Habitat. 



Number 



of 

 males. 



Number 

 of 



females. 



Total 

 adults. 



1916 

 May 9 



Under rubbish 



6 



81 



1 



5 



4 



28 



12 



5 



3 



6 



10 

 9 



12 



94 



4 



13 



4 



22 



6 



8 



4 



5 



12 



20 



6 



9 



11 



8 



8 



6 



20 



41 



18 



May 10 



do 



175 



May 13 



do 



5 



May 16 



do 



18 



June 29 



do 



8 



June 30 



AMieat heads 



' 50 



July 12 

 July 14 



Under Russian thistle of previous year. . . . 



18 



On wheat heads 



13 



July 20 

 July 24 



On wheat and thistle . . . . . 



7 



do 



11 



Aug. 1 

 Aug. 2 



On Russian thistle in waste areas of recently cut wheat field . . . 

 do 



22 

 29 



Do. 



On oat heads 



6 



Aug. 3 



On Russian thistle . . . .... 



3 

 12 

 8 

 2 

 2 

 20 

 34 



12 



Aug. 4 



do 



23 



Aug. 17 



do 



16 



Aug. 24 



do 



10 



Sept. 28 



In winter quarters 



8 



Sept. 29 



do 



40 



Oct. 2 



do . . 



75 





al 





Tot 



251 



313 



564 









LONGEVITY OF REARED ADL'LTS. 



A series of reared adults kept in life-history cages lived a minimum 

 of 19 days and a maximum of 48 days after maturity. The females 

 lived for a longer period than the males. The longevity of these in- 

 dividuals as adults was undoubtedly influenced by the unnatural con- 

 ditions under which they were reared to maturity. 



LONGEVITY OF ADULTS COLLECTED IN FIELD. 



In a series of 93 life-history cages, each containing a pair of 

 adults of Chlorochroa sayi collected in the field, the females lived a 

 maximum of 78 days with an average of 33 days and the males a 

 maximum of 66 days with an average of 23. Under field conditions 

 the adults undoubtedly live for three or four months, while the adults 

 of the last two generations remain in a dormant condition in their 

 hibernating quarters all winter. 



