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condition of the fly forms was noted. The record shows that on an average 
about 76 per cent of the larvae were parasitized, 8 per cent destroyed by 
desiccation, and 10 per cent remained viable and in healthy condition in the 
irrigated strip; whereas in the arid strip about 51 per cent were parasi- 
tized, 23 per cent destroyed by desiccation, and 21 per cent remained viable 
and in healthy condition. In this connection it should be considered that 
51 per cent average parasitism is about as high as the average has been in 
any one of the past 4 years on that land, and is much higher than in most 
years." 
COTTON INSECTS 
Airplane collections of insects made during September at Tullulah, 
La., by P. A. Glick and J. M. Yeates were as follows: "There was a total 
of 1,006 insects collected at the following altitudes (with the numbers 
of insects taken given in parenthesis): 200 feet (287), 500 feet (240), 
1,000 feet (211), 2,000 feet (115), 3,000 feet (96), and 5,000 feet (S7)5 
* * * The total collection of insects for the month of September, 1931, 
showed an average of 4.12 insects taken in a period of ten minutes as com— 
pared with 2.83 insects taken in the previous month." 
Life-history studies of the tarnished plant bug (Lygus pratensis L.) 
and the cotton plant bug (Adelphocoris rapidus Say) by K. P.Ewing, W. S. 
Cook, and R. L. McGarr at Tullulah, La., furnished the following informa-— 
tion: "Lygus pratensis—-— Egg—incubation records were secured on 1,136 eggs 
during September. The average incubation period was 8.04 days, the maxi- 
mum being 135 and the minimum 7. The host plants of these eggs were Eri-— 
geron canadensis and goldenrod. One nymph was reared to maturity, the 
number of days in the nymphal stage being 17. Adelphocoris rapidus-—— 
Nine egg-incubation records were secured during the month. The average 
incubation period was 10.7 days, the maximum being 14 and the minimum 10. 
Ten attempts were made to rear nymphs to maturity. Four individuals were 
successfully reared, with an average of 16 days in the nymphal stage. 
Cotton was used as the food plant of six nymphs and Chamaecrista robusta 
as the. food plant of four.” 
Population counts of the three important cotton mirids on 14 host 
plants in addition to cotton were made by Mr. Ewing and his assistants during 
september, by making a total of 12,600 sweeps with a hand net. "The aver-— 
age number of Psallus seriatus Reut. collected per 100 sweeps from croton 
during the first, second, third, and fourth weeks was 1,604.3; Adelphocoris 
rapidus collected per 100 sweeps from Chamaecrista robusta during the first, 
second, third, and fourth weeks was 146.3, 183.5, 268,3, and 117.4, res- 
pectively. The average number of Lygus pratensis L. collected per 100 
Sweeps from Erigeron canadensis during the first, second, third, and fourth 
weeks was 308.4, 177.5, 579.0, and 387.5, respectively. With the excep- 
tion of the collection of Lygus pratensis during the second week, these sweep- 
ings show that these insects increased in number on their respective prefer- 
red host plants during each successive week until the fourth week 

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