REPORT OF THE ENTOMOLOGIST. _ 63 
Professor Riley says: ‘‘A wheat plant pulled from an infested field 
in the spring of the year will generally reveal hundreds of these eggs 
attached to the roots, and at a somewhat later period the young larvee 
will be found clustering on the same and looking like so many moving 
atoms.” The eggs are not specially small, and when we consider the 
small size of the female which lays them (Dr. Shimer says that each 
female lays 500) this seems very large, until we reflect that they are 
not all deposited at once, and that after the laying of the first few 
others are probably developing in the ovaries, for the process of ovi- 
osition occupies from ten days to three weeks. It has long been 
nown that the eggs were laid in the ground, and an accurate descrip- 
tion was given by Professor Riley as early as 1866. Therelative abun- 
dance of the eggs upon the stalk and upon the roots may be changed 
somewhat, as Dr. Thomas has pointed out, by the character of the 
soil. Where the soil is very ae the majority of the eggs are 
doubtless laid upon the stalks, whereas if the earth is dry and easily 
enetrated the great majority of them will be found upon the root- 
ets and upon the stalks beneath the ground. 
According to Professor Riley the eggs hatch, on the average, in two 
weeks. The young larve begin to take nourishment as soon as pos- 
sible after hatching. They insert their beaks sometimes even, before 
they emerge from the earth, but more often crawl up the stalk, be- 
fore beginning to pump. They grow with considerable rapidity, 
and swarm over the stalk upon which they were born, walk- 
ing about with ease, and wandering from one stalk to another if oc- 
casion demands. As we have already shown, four molts are under- 
one before the insect reaches the perfect state, and generally from 
fe to seven weeks elapse from the hatching to the final molt. Dr. 
Shimer’s repeated observations show that at Mount Carroll, Il1., the 
imago usually appears in from fifty-seven to sixty days after the 
laying of the eggs and about forty-two days from the hatching of 
the larve. By the time the majority of the insects of this first gen- 
eration are full grown, or even before, the wheat has become too 
hard to offer them much nourishment, or harvest time has arrived, 
and they begin to migrate in search of food, Neighboring corn- 
fields offer a more tempting diet, and in seasons of great abundance 
they march in numerous colonies, moving by a common impulse 
from the wheat to the corn. Strange to say, although the com- 
moner form possesses wings the insect does not generally take 
flight, but prefers to walk along the ground. Occasionally, how- 
ever, at this time they take wings and scatter. This, however, is 
rarer when the insects are plentiful than when they are compara- 
tively scarce. Under no circumstances will these insects take to 
flight to escape danger. 
_ Dr. Shimer says: ‘‘No threatening danger, however imminent, 
_whether of being driven over by grain-reapers, wagons, or of being 
trodden under foot, will prompt it to use its wings to escape. Ihave 
tried all imaginable ways to induce them to fly, as by threshing among 
them with bundles of rods of grass, by gathering them up and letting 
them fall from. a height, etc., but they invariably refused entirely to 
use their wings in escaping from danger.” The migration takes ete 
often and, according to some authors, usually before the majority of 
the broods have attained full growth. There are always many im- 
_ mature individuals among a large host, and often the army is com- 
ae almost entirely of such. In fact, at these times there is apt to 
e a general confusion of so-called larvee, pups, and adults, owing 
