352 
SOUTH-AFKICAN BUTTERFLIES. 
times almost obsolete (as in Pyrameis, fig. 4), so that the discoidal cell appears to be 
open. In the hind-ioing there are never more than two of these nervules, as only 
one discoidal nervule exists ; and of them the second (lower) one is often obsolete or 
absent entirely (as in Pyrameis, fig. 4 ; Lihythea, fig. 5 ; and Ehopalocampta, fig. 9). 
h. Interno-median nervule. In fore-wing only. This minute transverse nervule is shown 
in fig. 8, uniting the median and submedian nervures near their origin. It is only 
found in the Papilionince and Morphitce. 
k. Precostal nervure. In hind-wing only. This short curved nervure, close to the base, is 
almost always simple, but in Papilio (fig. 8) and several allied genera, and in the 
Sub-family Brassolince, is forked, its lower branch being then united to the costal 
nervure so as to form a small prediscoidal cell.i The precostal nervure is wanting 
in Lyccena (see fig. 6), and apparently throughout the Family Lyccenidce, as well as 
in several genera of Pierince. 
In fig. 4 [Pyrameis] is shown, along the hind-margin of both fore and hind wings, the fringe 
{cilia) of hairs or hair-like scales more or less developed throughout the Lepidoptera. 
3. In the figures of the Head, figs, ia and 5A are viewed from below, fig. 9A from above, and 
the remainder from the side. The following letters are used throughout to denote the several 
organs, viz. : — 
aa. Antennce. These many-jointed organs vary much in length and thickness, and the 
thickening or club at their tip is also very variable in the difi"erent groups as regards 
size, shape, and gradual or abrupt formation from the main antenna. In the 
Hesperidce (see fig. 9A) the antennae are widely separated at their origin, springing 
from each side of the wide head, and the point of the club is prolonged into a 
slender acute bristle, either bent at an angle or hooked. 
pp. Labial palpi. These organs, springing from the labium or under lip, are three- jointed, 
but the extent and form of the third (terminal) joint only is readily perceptible, 
owing to the second (middle, and usually much the largest) and first (basal) joints 
being coated with scales and hairs. The extraordinary length of the palpi in 
Lihythea (see fig. 5 a) is due, however, to the unwonted development of the third 
joint ; while in Papilio (see fig. 8a) these organs are so short as to rise only half as 
high as the head, not projecting forward at all. 
ee. Compound Eyes. These great organs occupy a large space on each side of the head. 
They are always prominent and globose, and present but little variation in size or 
form. 
t. Trunk or haustellum. This consists of the greatly modified maxillce (second pair of jaws 
in biting insects), forming together a tube for sucking liquid food. When not in use 
it is spirally rolled up between the labial palpi. It is much longer in the Hesperidce 
than in other butterflies. 
4. In the figures of the Legs (iB, 8b, and 9B) the various parts are distinguished by the 
following letters, viz. : — 
a. Leg of first (front) pair*. 
b. Leg of second (middle) pair. 
c. Leg of third (hind) pair, 
f . Femur or thigh. 
t. Tibia or shin, 
ts. Tarsus or foot. 
In fig. IB all three legs of Danais are shown (a. b, c). The front leg is not a quarter the size 
of the middle or hind leg, and its tarsus is reduced to a single joint, with the minutest rudi- 
ments of two other joints (see fig. a', magnified), instead of having the five joints and pair of 
terminal claws possessed by the other (normal) legs. The spurs at the end of the tibia are 
unusually small in both middle and hind legs. 
In fig. 8b the front and hind legs of Papilio are given (a, c). The front leg (a) is quite as 
fully developed as the others, the tarsus possessing the five usual joints and the terminal claws. 
The spurs at the end of the tibia are well developed in the middle and hind legs, and the tibia 
bears on its inner (inferior) edge a large acutely -pointed process. 
In fig. 9B [Rhopalocampta) the front and hind legs are shown (a, c). As in the Papilionidce, 
the front leg is fully developed, and also bears a process (similar to that in Papilio) on the tibia. 
On the tibia of the hind-leg (c) there is a second pair of strong spurs at a little distance above 
the ordinary terminal ones. The femur of all the legs and the tibia of both middle and hind 
legs are densely clothed with hair. 
Note. — The student will find it serviceable to consult this Plate, and the explanatory details 
here given, in connection with the remarks on the structure and classification of butterflies 
above offered (pp. 15-22) under the heading of " Rhopalocera ; " and also with the particulars 
as to distinguishing characters given under each Family, Sub-family, and Genus in the body of 
the work. 
1 The smaller and less complete prediscoidal cell found in several Hesperidce (see Rhopalocampta, 
£. 9) is differently formed, between the costal and subcostal nervures, at the very base of the discoidal 
ceU itself, by the downward flexure and sub-angulation of the subcostal nervure. 
