NYMPHALIDAE 
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old. Before hatching takes place, the dark head of the larva 
shows through the shell, and this, combined with the white 
keels, gives the egg a dull purplish effect. The egg state lasts 
about twenty days. 
Both in colour and shape the eggs of N. poly chlorus and 
A r . antiopa are very similar. 
Larva. The larva makes its exit by eating away the crown 
of the egg. Upon emergence, the entire brood crawl to a 
young leaf, spinning a web as they go over the surface, and 
then all assemble together and soon start feeding. 
Through all the stages, the larvae are gregarious and 
remain so until fully grown, when they disperse and wander 
away in search of a suitable site for pupation. When the 
larvae have been living on the topmost branches of a tall elm, 
they drop to the ground to avoid a long climbing descent. I 
have seen them falling one after the other from the top of a 
very tall elm growing beside a roadway, upon which they 
fell and then rapidly crawled away. 
When fully grown after the fourth moult, the larva measures 
41-3 mm. in length. The head is bilobed, with a deep notch 
on the crown. The colour is black, studded with warts and 
tubercles of various sizes, each bearing a whitish hair. The 
body is almost cylindrical, excepting for the first segment, 
which is disproportionately small. The body is covered with 
long amber-coloured, sharply-pointed spines capable of pene¬ 
trating the fingers. The first segment is spineless, the second, 
third and last segments have each four spines, the remaining 
segments have seven each ; in all, sixty-eight. 
The ground colour is velvety-black, except for the anterior 
sub-dorsal area of each segment ; the surface is sprinkled 
with white warts, each emitting a fine white hair, giving the 
surface a grey appearance. Down the centre of the back is 
a black line bordered with amber colour, and each spine is 
situated on an amber band. The sides are checkered with 
pale amber ; the ventral surface is freckled with purplish- 
grey ; the claspers are ochreous, the legs and anal claspers 
black ; the last two segments have each a black, rounded 
dorsal disc, the largest one on the anal segment. 
Besides Elm and Sallow, the larvae have been found feeding 
on Aspen, White-beam, Birch, Cherry and Pear. 
