ALFALFA WEEVIL. zi 
a substitute for that valuable crop. It is therefore particularly de- 
sirable that farmers in the western mountains and plains should 
learn the appearance of the different stages of the weevil and be pre- 
pared to protect their crops. 
DESCRIPTION OF THE WEEVIL IN ITS DIFFERENT STAGES. 
THE FULL-GROWN LARVA. 
The insect is most easily discovered, during the early years of its 
presence in new fields, in the form of the full-grown larva (fig. 2). 
It is then a green wormlike creature one-fourth of an inch long, with 
a black head and a faint white stripe down the middle of the back, 
and it feeds upon the leaves of the alfalfa mainly during late May, 
June, and early July. It can be found by sweeping the tops of the 
plants with an insect net,.or by looking for the notches in the leaves 
where it has fed. When the larve are numerous they destroy most 
of the tender growth (fig. 4), causing the 
tops to appear white and making the field 
look at a distance as if frostbitten. 
THE NEWLY HATCHED LARV-®. 
The newly hatched larve are harder to 
find. They are only about one thirty-sec- 
ond of an inch long and remain hidden in 
the partly unfolded tips of the plants, ra. 5—1ne alfalfa weevil: Cocoon 
where they are not easily. seen of caught  sttached to) dead) leaves Muth 
é 2 A enlarged. (Original.) 
by the net.- Their color is yellowish green, 
excepting the head, which is black. The color changes to green at 
the first molt, or shedding of the skin, and there is little change ex- 
cept in size during the two or three molts which follow, varying in 
number with the season of the year ia which the larval life is spent. 
THE PUPX AND COCOONS. 
The pupal form is the one in which the change from the larva to 
the adult takes place. The pupa is contained within a delicate, 
oval, netlike cocoon (fig. 5), woven of a few white threads and 
attached, sometimes to the lower part of a green stem, sometimes to 
rubbish on the ground, and often to the inner side of a curled dead 
leaf. The pupa within this cocoon is somewhat like the larva in 
color, but more like the adult beetle in form, becoming still more 
like it in both respects as it approaches maturity. 
THE ADULTS. 
The adult is harder to find than the larva, but is present m the 
field throughout the whole year instead of the summer only. It is 
an oval brown beetle, three-sixteenths of an inch long, with a promi- 
nent snout projecting downward from the front of the head. The 
