582 
THE STUDY OF INSECTS . 
the peas is not so generally understood. The eggs of the 
Pea-weevil are laid upon the pod while the peas are quite 
small; when the larvae hatch they bore through the pod 
into the young peas. Here they feed upon the substance 
of the seed, which ripens, however, and in some cases will 
germinate when planted. The larva before transforming 
eats a circular hole on one side of the seed, leaving only a 
thin scale, which is easily pushed away by the mature beetle. 
The adult is about one fifth inch in length ; it is dark brown, 
with a few white spots on the wing-covers, and one on the 
prothorax near the middle. Sometimes the beetles leave 
the peas during the autumn or winter; but as a rule they 
remain in the seed till spring, and are often planted with it. 
Seed peas should be placed in water, and the infested ones, 
which will float, should be picked out and destroyed. This 
species is not known to oviposit on dry peas. 
This and other grain-infesting insects can be destroyed 
by placing the grain into a close receptacle with a small 
quantity of bisulphide of carbon. 
The Bean-weevil, Bruc/ius obtectus (B. ob-tec'tus).—This 
species resembles the preceding quite closely; but it is a 
little smaller (Fig. 709), and lacks the white markings char¬ 
acteristic of B. pisi. It infests beans, and often several indi¬ 
viduals inhabit a single bean. The eggs are laid within the 
pod, being pushed through a slit which the female gnaws 
through the pod. This species will oviposit on dry beans, 
peas, and other grain, and will continue to breed for many 
generations in stored beans and peas. 
Family Tenebrionid^E (Te-neb-ri-on'i-dae). 
The Darkling Beetles . 
The darkling beetles are nearly all of a uniform black 
color, although some are gray, and a few are marked with 
bright colors. The different species vary greatly in size and 
