ee 
hr 
THE GRAIN BUG. 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. 
PROPORTION OF SEXES, 
Under field conditions the females of Chlorochroa sayi are slightly 
more abundant 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 1V.—Proportion of sexes of Chlorochroa sayi in different habitats through- 
out the active season. 
Number | Number Total 
Date. Tlabitat. of of 
males. | females. | 2U!ts. 
1916 
May Gliry el ere UTID lor S Nes pec aeetaz eyes been fv sicrath cid, ayetatoicin nce aveicle Mfaleeele 6 12 18 
MayelOn|Eese reap Pe tere escorts weet ted ee Ui eS Seis e 81 94 175 
Inlenye TBE o Se OOo séocs bse Soe SAE ARORA as Ba URN, hee eee Em etn rae ars a 1 4 5 
May 16]..-.. QOS SSS AE SOTERA a pra et a ge ie ee 5 13 18 
June 29 |..-.. OIG Sb a8n5 5 OOS ESS ae OAS A Ee se tet pee aeepan eas 4 4 8 
Mes OMmVneATNCAGSE pie me ee ie es a oe soe eee oot Boek 28 22 50 
July 12 } Under Russian thistle of previous year.................-------- 12 6 18 
TlVvalamOnewheatpheadste ag. 585 2s Nie eee los Sen sec ce cece 5 8 13 
lye ONPOnawheatangithistlestes.s- cece asacecessascces scene ees ce eccene 3 4 7 
July 24 |..... LOR ee esa ens moc em en Coe te eu eee SORES et 6 5 11 
Aug. 1] On Huesian thistle in waste areas ofrecently cut wheat field 10 12 22 
AGTH, BO Wes & Ses COND) es eS sos Ae RN eae st NU A pene Rw 9 20 29 
Do. On Sat ORG IS 36 ae Gas aN aT SII BR eats SOU eer es eae Hee NC eee 6 6 
ATION Ome USSIATAEMiStlee eee ai nA EN nh ys eM oe Skok 3 9 12 
ANGER, GUS ae OSE 656.06 8S BOE ee SRO Et ety TOUS gap ee ale Sane Aes aia re 12 11 23 
ANES, Al lesson CDSs SSE S Hes SI a Ee AU 8 8 16 
INTIS OFS Ne Oo hs SAGE RAA SE SHE GRU NER BAO ea ate a Ni ee rp 2 8 10 
Sepieezsa eine witter duarterse acento se ee ee Ne ee ssc e eck 2 6 8 
Sept. 29 |..... Ga scesSoGe ou SHE SASS eae eee Creeley ROE ce cl eg er cnt a ane 20 20 40 
Oct. 2 SOS SESS GSS Toe ER aE a Raa Ui eg SI ata Hoa Nea a 34 41 75 
INO BOSS SOUS SESE SD SE ees RC ae ee tapincyer trad ate aL ep 251 313 564 
LONGEVITY OF REARED ADULTS. 
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 sayz 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. 
