328 
PIERIDAE 
The pupae of C. hyale and C. croceus are almost identical, 
the only distinction apparently constant is that the beak of 
the former is straight, which in the latter is slightly upturned ; 
also, the apex of the wing in C. croceus does not reach so far 
down the abdomen as in C. hyale. 
The food plants of C. hyale consist of different kinds of 
Clover, usually Trifolium repens and T. pratense ; Lucerne, 
Bird‘s-foot Trefoil and other Leguminosac. 
Imago. The average expanse of the wings is 50 mm., 
large examples measure 59 mm. 
A distinct sexual colour usually exists, the male being 
yellow and the female white. 
Male. (Upper Side.) . The ground colour is primrose-yellow, 
varying in intensity. The fore wing is powdered with black 
scales over the base ; at the end of the discoidal cell is a more or 
less rounded rich black spot, and the apex and outer margin 
are broadly black, which is broken up by a series of primrose- 
yellow spots. The hind wing has an ill-defined marginal black 
band, which is usually almost obliterated by the numerous 
yellow spots, except on the outer edge. In the centre of the 
wing is an orange spot in the form of the figure 8, and the 
lower half of the wing from the base is powdered with black 
scales. 
(Under Side.) The fore wing is primrose-yellow, the apex 
and the whole of the hind wing varying from deep golden- 
yellow to greenish-yellow, very finely powdered with black 
scales, giving some specimens a dusky hue. On the fore wing 
is a sub-marginal series of brown-pink and black spots, and a 
black central spot as on the upper side. On the hind wing 
is a central double lilac-silver spot encircled with brown-pink. 
On the costa is a square blotch and a basal blotch, also a 
series of sub-marginal spots, all of the same brown-pink colour. 
The wings are finely outlined with rich rose-pink ; the antennae, 
front of the thorax, and the legs are all of the same pink 
colouring. 
Female. The female is similar to the male, except that 
the ground colour is usually of a greenish-white. 
Life of Imago. The Pale Clouded Yellow is of vigorous 
constitution, having a powerful and rapid flight, and its life 
extends between four and six weeks. 
