the legs
are black. In the other larva, (Fig. 15, _b_,) on the contrary, the head
is of a pale color, the first joint behind the head is tinged with dusk
and edged all round with black; there is but a single row of spots along
the side of the body, and the legs are pale.
Figure 14, _d_, _d_, exhibits the true Colorado potato-bug; Figure 15,
the bogus Colorado potato-bug; each of its natural size. Figure 14, _e_,
shows the _left_ wing-case enlarged, and Figure 15, _e_, an enlarged leg
of the latter. On a close inspection, it will be perceived that in the
former (Fig. 14, _e_) the boundary of each dark stripe on the wing-cases
toward the middle is studded with confused and irregular punctures,
partly inside and partly outside the edge of the dark stripe; that it is
the third and fourth dark stripes, counting from the outside, that are
united behind, and that both the knees and feet are black.
In Figure 15, _d_, on the contrary, it is the second and third
stripes--not the third and fourth--counting from the outside, that are
united behind, and the leg is entirely pale, except a black spot on the
middle of the front of the thigh. The eggs (Fig. 14, _a_, _a_, and Fig.
15, _d_, _d_) are yellow, and are always laid on the under side of the
leaf in patches of from twenty to thirty; those of the bogus are of a
lighter color. Each female of the true Colorado potato-bug lays,
according to Dr. Schirmer, about seven hundred eggs. In about six days
the eggs hatch into larvae, which feed on the foliage of the potato plant
about seventeen days; they then descend to the ground, where they change
into pupae at the surface of the earth. The perfect beetle appears about
ten to fourteen days after the pupa is formed, begins to pair in about
seven days, and on the fourteenth day begins to deposit her eggs. There
are three broods of this insect every year. Neither geese, ducks,
turkeys, nor barn-yard fowl will touch the larva of the Colorado
potato-bug when it is offered to them, and there are numerous authentic
cases on record where persons who have scalded to death quantities of
these larvae, and inhaled the fumes of their bodies, have been taken
seriously ill, and even been confined to their beds for many days in
consequence. It is also reported to have produced poisonous effects on
several persons who handled them incautiously with naked hands. Various
plans have been tried to destroy this persistent enemy of the potato
plant. Powdere
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