2 94 PIERIDAE 
black band is very glossy, of a purplish-grey colour, and 
thickly sprinkled with whitish-grey spots. The head is dull 
black and hairy ; the anal segment, including the claspers, 
is also black ; • the legs and spiracles are shining black. 
The larvae rest stretched out along the twigs, often in 
small companies, lying side by side. The branches and leaves 
are always spun over with silk. Occasionally the larvae hang 
suspended by a web. If touched several times, they suddenly 
start crawling rapidly; they neither feign death nor roll in 
a ring. 
The transformation from the spinning-up of the larva to 
pupation occupies about fifty-five hours. 
Pupa. The pupa averages 25 mm. in length ; the head is 
knobbed in front ; at the base of the antennae is a short,, 
sharply-pointed spike; the thorax is swollen and keeled 
dorsally; the waist is sunken ; the anal segment terminates 
in a flattened, slightly-curved horn, bearing the cremastral 
hooks, which are firmly attached to an ample pad of silk. 
A girdle of silk also passes round the body at the waist. 
The normal ground colour is a pale greenish-yellow, some 
approaching a greenish-white, speckled and dotted with black 
and conspicuously spotted with yellow on the frontal knob, 
dorsal and lateral keels, pro-thorax, base of the wings and 
anal extremity. 
The ground colour varies, also the markings, in size ; and 
the colouring is affected by the surroundings. Pupae spun 
up on light objects assume the lightest tints ; those upon a 
green surface are green, while those with grey or black sur¬ 
roundings become grey or dusky in colour. 
The pupal stage occupies about twenty-one days, according 
to temperature. 
Imago. The Black-veined White expands from 69mm. to 
76 mm. The sexual difference is distinct. The male is whiter 
and more densely scaled, and the nervures are black. The 
female is semi-transparent and the nervures light brown. 
Male, (Upper Side.) The upper side is milk-white; the 
marginal outline and nervures are black and terminating in 
triangular dusky blotches, which are larger on the fore wings 
than on the hind pair. These blotches vary in size in different 
specimens ; they form in some a broad, dentated, continuous 
