1146 
Journal of Agricultural Research 
Vol. XXXI, No. 12 
Longevity of the Adult 
Only eight complete longevity records have been secured from 
observations in the mating cages, four of these being for females 
and four for males. The four females lived a total of 199 days, 
giving an average female longevity of 49.8 days. The four males 
lived a total of 193 days, giving an average male longevity of 48.25 
days. The maximum individual longevity of the females was 55 
days; the maximum male longevity 73 days. Although little differ¬ 
ence between the longevity of the sexes is shown above, there are 
indications that on an average the females are longer-lived than the 
males. The survival of 37 field-collected females in the mating cages 
gave an average survival of 10.92 days from the date of collection. 
Thirty-six males lived an average of 9 days. Of course no data were 
available showing the ages of these adults at the time of collection. 
HABITS OF THE SPECIES 
The adults are gregarious, not only in regard to each other but also 
in regard to the larger stages of the immature forms. They are 
commonly found in groups on the plants from which they derive 
their nourishment, the groups including both sexes of the adult and 
frequently considerable numbers of nymphs of the third, fourth, and 
fifth stages; sometimes, but very rarely, nymphs of the second stage. 
These groups move about from plant to plant, keeping more or less 
together, the extent of their movements apparently being controlled 
by the quantity of food which they are able to find. Frequently 
great numbers of the insects concentrate upon a certain group of 
plants which are evidently supplied with large quantities of the 
sought-for juices, and possibly hundreds of the insects will be found 
upon the plants for several days, after which, having apparently 
exhausted the food supply, they migrate to other plants in the neigh¬ 
borhood. The plants which have been u worked over” do not 
appear to be damaged to any appreciable extent by the wholesale 
visitation, although stalks have several times been observed so 
weighted with the insects that they have been bent nearly to the 
ground. 
Mating appears to occur at any time after the adults have reached 
the age of 2 days. The eggs are generally deposited under the sur¬ 
face of the ground, a dead leaf or fruiting capsule of the host plant 
usually being buried with them for food for the nymphs after hatching. 
When no leaf or fallen capsule is available, the females sometimes 
oviposit in the soil* immediately around the stem of the host plant 
where it emerges from the ground. Occasionally a simple groove in 
the ground is used for oviposition. Eggs may occur singly or in 
clusters of from 2 to 25 or 30, adhering together very slightly, although 
easily separable without damage. The act of oviposition has been 
observed on two or three occasions. When a suitable capsule had 
been selected, the female would deposit two or three eggs, then care¬ 
fully cover them with soil, pulling the particles over them with her 
feet. More eggs would then be deposited and covered in their turn, 
until finally the entire capsule would be buried under the surface. 
These observations were all made under insectary conditions, since 
