PART IV.
Nores oN THE Lire History.
Eggs are laid in the soft green tissues near the tips of stems and
branches, usually in the nodes. The average incubation period is
eighteen days. The nymphs move actively when disturbed; they are
responsible for considerable damage during their five instars which
average respectively four, three, four, five, and six days, a total of 22
days. Adults are very active and they quickly take to flight when
disturbed; they feed on the same parts as the nymphs and also on
somewhat older leaves. The minimum pre-oviposition period was
found to be 10 days. Four eggs every day was the usual number laid
throughout the egg-laying period, and the maximum number of eggs
laid by a female in the laboratory was 454. The maximum longevity
of the female was 126 days and that of the male 75 days.
DESCRIPTION OF STAGES.
The egg is translucent, creamy-white, circular in cross-section,
bluntly pointed at both ends, elongated and slightly curved. The
length is 1.75 m.m. and the maximum breadth 0.25 m.m. At the outer
end are two delicate white filaments, 0.36 m.m. and 0.18 m.m. long,
probably for respiratory purposes; around this end of the egg and
covering the bases of the filaments is a brownish granular substance
secreted by the bug, apparently for protection of the egg. The sole
indication of the presence of eggs are the white filaments protruding
from the plant tissues; careful examination is necessary to locate the
eggs, the filaments being barely visible to the unaided eye.
The nymph is flattened and rather broad in proportion to the
length as compared with the adult. There are short hairs on all parts
including antenne, legs and wing-lobes. The general colour dorsally
is pale clay-yellow with paired vermillion spots on the abdomen
surmounted by tufts of short brown hairs; latero-dorsally between the
sixth and seventh abdominal segments is a pair of dark brown spots
carrying similar hairs. The legs are creamy white with black spots
on the femora and tibize but not on the tarsi. The ventral surface is
pale yellow. The eyes and first antennal joint are vermillion coloured,
the second antennal joint is ereamy white with a yellow band near the
apex, the third is black, and the fourth reddish-brown. The nymph
feeds on the underside of the leaves producing the characteristic spots.
The adult is clothed by short hairs on all parts including the
hemelytra. Dorsally the colour is ochrous brown with a median 0.5
m.m. broad, black line on the head and prothorax narrowing on the
scutellum and joining the black membraneous part of the hemelytra.
Ventrally the body is black with a median pale yellow area extending
along the thorax to the fifth abdominal segment. The coxai, femora,
and tibie are black while the trochanters and first three tarsal joints
are pale yellow, the last two being dark brown. The eyes are Indian
red. The first three segments of the antenns are black and the fourth
is ochrous brown; the lengths of the joints are approximately
proportional to the numbers 2—6—4—1. The sexes are slightly
different in size, the female being 10 m.m. long and 8 m.m. broad at
the base of the hemelytra, while the male is 9 m.m. and 2.5 m.m.
excluding the antennw; the ovipositor is indicated by a ridge in the
median line from the seventh abdominal segment to the tip of the
abdomen.

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