94 DEPARTMENT BULLETIN 179. 
the sunlight is reflected from the dorsal surfaces of the insects and 
adds to their conspicuous appearance. At this time at least 95 per 
cent of the adults present in the vicinity may be seen without moving 
any part of the plants. When disturbed, however, most of the adults 
immediately drop to the ground and seek cover. 
ODOR AND EXCREMENT. 
The characteristic odor of the adults and nymphs is not generally 
noticeable in the field even when the insects are present in large 
numbers. During thrashing operations, however, many farmers 
have reported that the odor given off by the grain bug was so 
noticeable as to cause much discomfiture to the workers. This was 
probably due to the fact that large numbers of the insects had con- 
centrated about the grain shocks and had given off the offensive 
odor when disturbed. In life-history cages this offensive odor is 
not noticeable unless the insects are roughly handled. 
The excrement of Chlorochroa sayi is a yellow-green fluid and is 
commonly found on the leaves or stems of the host plant. It varies 
in size from mere specks deposited by the young nymphs to circular 
masses 5 millimeters in diameter deposited by the adults. 
DAILY ACTIVITY. 
During the calm, pleasant weather of the summer months the adults 
of Chlorochroa sayi are active and feeding throughout the greater 
part of the day and night. They are not affected by the excessive 
heat of midday, as is true of the nymphs, but are more active and 
do most of their feeding while high temperatures prevail. (See 
Table VIII.) During periods of high winds, rain, or hail storms 
and nightly temperatures below 60°, the insects cease their activities 
and seek shelter, generally under some object on the ground or around 
the bases of their food plants. 
TABLE VIII.—Daily activity and feeding habits of adults of Chlorochroa sayi, 
July 15, 1916. 
Wire cage 3 by 3 by 3 feet over wheat plot—2 male and 4 female adults. 
Hour. | Temperature. 
Weather conditions. Observation on activity. 
| Shade.} Sun. 
A. M. opie 2) De 
4 63elacs4ee 5 on heads in same po- 
sition as at 9 p. m. last 
“loud night; at least 2 have 
Maries stAteks) Seo8 eet re tee a hae eee setze inserted into grain 
head. 
4.30 0778 Bee ee Do 
5 BQ eke | Sunrise: cloud yi < = 2222-4 pen = soe eee ee eeee 4 resting 
5. 30 G42. Sats E 4 resting 
6 OOH Pisa oe Cloudy......------+++--++-2+-22+ 2222 ee eee eee ee eee eee| 12 resting 
6. 30 GO ELS hes Partly: cloudy 1.2: . ies Jo 552 PLA SA See CE 3 resting. 
7 72 |-------- \cloudy a ek RS ROE cet Sera rs OMS ARE ee Oe ioe Sk Eee van { Do. 
7,30 ‘Biel ARE ein 3 resting and feeding. 
e. 
