
a 9 
was reached, when there was a considerable diminution in population. From 
200 to 500 sweeps were made on each plant during each week of the month. 
The greatest number of insects per 100 sweeps was collected on September 
17, when 4,537 adult and 1,572 nymph Psallus seriatus were collected from 
croton, 186 adult and 277 nymph Adelphocoris rapidus were collected from 
Chamaecrista robusta, and 409 adults and 431 nymph Lygus pratensis were col- 
lected from Erigeron canadensis. Sweepings on cotton showed there were 
more Adelphocoris rapidus in the cotton than any other mirid; however, 
this insect was not present in large enough numbers to do any material dam- 
age. The scarcity of mirids in cotton during September was probably due 
to the maturity of the plant." 
Oviposition records on the pink bollworm taken in the insectary at 
meestdlO, 1ex., by W. L. Owen, jr., and assistants indicate that "with fe 
males from square material there is a gradual decrease in vitality and pro- 
ductive powers with each succeeding generation, while with females from 
boll material vitality and productive powers seem to increase with each 
generation. This may, in a measure, account for the jump in infestation 
the latter part of the season each year." 
Four experiments have been completed in the poison-plat tests con- 
ducted by F. F. Bondy at Florence, S. C., in connection with research aimed 
at the control of the cotton boll weevil. In the first of these experi- 
ments an untreated plat produced 1,063 pounds of seed cotton per acre; a 
plat receiving three early applications of molasses mixture, followed by 
three later applications of calcium arsenate dust, produced 1,435 pounds 
per acre; while a plat receiving three early applications of molasses mix-— 
ture, followed by five later applications of calcium arsenate dust, pro-— 
duced 1,505 pounds per acre. In the second experiment an untreated plat 
produced 1,155 pounds of seed cotton per acre, while a plat receiving so- 
dium fluosilicate produced 1,140 pounds per acre. In the third experiment 
an untreated plat yielded 1,255 pounds per acre, while a plat receiving 
only three early applications of 1-l=1 molasses mixture produced 1,323 
pounds per acre, The fourth experiment gave a yield of 947 pounds per acre 
on a plat receiving no treatment and a yield of 1,150 pounds per acre on a 
plat receiving calcium arsenate dust after 10 per cent infestation, the 
treatments being continued throughout the season. 
E. W. Dunnam, College Station, Tex., reports as follows on the pop-— 
ulation and migration of cotton bollworm moths:" Information obtained by 
the use of the two-row wheel trap indicated that the peak of population was 
reached by August 20. The population decreased to practically nothing on 
September 1. Incidentally there were practically no eggs being deposited 
when the peak of population was reached. The proportion of males to that 
of females was about equal. There were no bollworm moths taken from standard 
upright screens." , 7h 
The cotton perforator infestation dropped rapidly during the month, 
_according to T. C. Barber, of the Calexico, Calif., sublaboratory. "This was 
due to the effect of cooler temperatures as well as to the greater effective-— 
ness of controlling agencies. * * * The average infestation during Septem- 
ber was about one-seventh of the average infestatio for August." 
