Dec. is, 1925 Observations on a Cotton Insect New to the United States 1147 
the closest search has as yet failed to disclose eggs in the field under 
natural conditions. 
From the manner of oviposition, it is very difficult to determine 
the exact number of eggs deposited. Although a considerable num¬ 
ber of eggs were secured in cages containing no soil, there did not 
appear to be as many per female as there should have been, and it 
is probable that oviposition was curtailed by unnatural conditions. 
The greatest number of eggs definitely counted from two females 
was 107, laid on two consecutive nights (56 eggs on the night of 
July 26-27 and 51 eggs on the night of July 27-28). No eggs were 
subsequently deposited, so that the eggs, in this case, averaged 53.5 
per female. Usually, however, only about 15 to 30 eggs were ob¬ 
tained from each female in this type of cage. It has not been possible 
to make definite counts of eggs deposited underground in the cages 
containing soil. 
SUMMARY 
During the past year Dysdercus obscuratus Distant, an insect of 
the cotton stainer group new to the United States, has been found 
in cotton fields in Texas. 
The insect occurs, perhaps continuously, from Central America, 
and probably farther south, along the Gulf Coast of Mexico to the 
lower Rio Grande Valley of Texas. 
Probably the area of infestation is extended mainly by flight. 
At Brownsville, Tex., the species feeds upon four wild plants, 
Sida carpinifolia L., the common ragweed (Ambrosia artemisiaefolia ), 
wormwood (Ambrosia elatior L.), and Verbesina encelioides (Cav.) 
B. and H. 
Whether the insect is economically important has not been defi¬ 
nitely determined. 
The eggs are deposited in clusters, usually under the surface of the 
ground. The incubation period is about five days in midsummer. 
The nymph has five stages. The duration of each stage varies 
with the time of year in which it occurs. 
In the .lower Rio Grande Valley the average period of development 
from egg deposition to the appearance of the adult insect was found 
to average 32 days in midsummer, 55 days in the fall, and to range 
from 87 to 108 days in the winter. 
Male adults in cages were found to live an average of 48.25 days; 
females in cages lived an average of 49.§ days. 
The adults and larger instars of the nymph stage are gregarious, 
being found commonly in groups on the plants from which they 
derive nourishment. These groups move about from plant to plant. 
Frequently great numbers of insects will concentrate upon a certain 
group of plants and remain there for several days. 
