238 
REPORT ON ECONOMIC ENTOMOLOGY 
Pests of trees 
and shrubs 
A pest of 
orange and 
lime trees 
VII. Animates injurious to Trees and Shrubs 
The Orange Tree Butterfly 
rapilio dp.molem 
Plate XXXII 
This is the only insect pest of any importance that lias, np to the present time, been 
noticed attacking orange trees in this country. Specimens of the adults have been received 
from the Bahr-El-Ghazal and the larvai have been recorded as defoliating orange and 
lime trees at the American Mission Station on the Sobat. It is moderately plentiful in 
Khartoum. 
It is found throughout Africa and is said to be the cause of considerable damage to 
young citrus trees in the Transvaal. 
In the Sudan the larvai have only been seen on citrus trees, but if these are wanting 
they are able to feed on various other plants. 
Eijg (fig. 7).—In shape the egg is spherical with the surface attached to the leaf 
or twig slightly flattened. Colour, yellowish-brown. Diameter, 1-25 nun. 
Previous to hatching, a dark spot appears near the top of the egg. After hatching, the 
empty egg shell, which usually remains attached to the leaf, resembles a small seed pearl. 
Larva (fig. 2). — A stoutly built caterpillar, with the second, third and fourth 
segments much thickened, giving it a hunch-backed appearance. 
The larva passes through two distinct stages before attaining maturity. 
On first hatching it is very conspicuous in colour, but is protected by its close 
resemblance to the excreta of a small bird. 
Head, dark brown. Body, brownish to bluey-blaek. First segment and sides of the 
second segment yellow to white. Sides of the fifth and sixth and dorsal surface of the 
seventh and eighth segments yellow to white, forming a broad irregular V-shaped mark. 
Sides of the tenth and eleventh segments yellow to white. Anal segment white. A 
pair of chestnut yellow forwardly-projecting tubercles or horns on the first segment. Two 
longitudinal rows of tubercles on the dorsum corresponding in colour to the segments on 
which they are situated. A transverse row of six tubercles on the third segment and a 
similar row of four on the fourth segment. 
In the second stage (fig. 5) the larva is bright green in colour, sometimes wdth a 
yellowish tinge. 
Head, dark brown. Junction of first and second segments, black. A transverse band 
varying in colour from brown to black and studded with small tubercles, anteriorly placed on 
the third segment, and a similar band, posteriorly placed on the fourth segment. These 
bands meet at the sides, enclosing a green area. Fifth segment, anteriorly edged with black. 
A brown to black jratch begins on either side of the seventh, and extends upwards and 
backwards on the eighth and ninth, segments. Anal segment, brown to black. On the first 
segment is a pair of large tubercles, chestnut-brown in colour, and a similar pair is situated 
on the anal segment. Minute chestnut-brown tubercles on the eleventh and twelfth 
segments. 
Jointed legs, chestnut-brown. Prolegs, white. Venter, greyish-white to grey. 
In common with the other members of the family Vapilionuhe, the larva possesses in 
both stages a retractile organ, situated on the first segment, known as the osmeterium. 
A mature larva varies from 35 to 40 mm. in length. 
Pupa (fig. 1). — In colour the pupa is usually ashy-grey. It is somewhat spindle-shaped 
and bears on the head two serrate horns and on the thorax a pronounced dorsal projection 
and two small lateral projections. 
