THE PAINTED LADY 
143 
to accomplish than the hours of daylight would allow, so 
that enforced nocturnal habits have resulted in consequence. 
Upon the arrival of the spring immigrants in May and 
June, when they have probably already paired, they spread 
over the country and lay their eggs, chiefly during the first 
half of June. These eggs produce butterflies towards the 
end of July and August. These pair and produce another 
brood which are on the wing by the end of September and 
in October. The butterflies of this emergence also pair and 
deposit their eggs, resulting in larvae sometimes being found 
in late autumn ; these, however, perish in the first spell of 
cold, damp weather, which is fatal to the species in all its stages. 
Egg Laying. The eggs are laid 
singly on the upper surface of the 
leaves of various kinds of thistles, 
including the Field Thistle ( Carduus 
acanthoides) , the Spear-plume Thistle 
(C. lanceolatus) , the Creeping Thistle 
(C. arvensis), the Nodding Thistle 
(C. nutans), and the Dwarf Thistle 
(C. acaulis) ; also occasionally on 
Burdock ( Arctium lappa), Mallow 
(Malva sylvestris), the Stinging Nettle 
(Urtica dioica) and on flower buds 
of Viper's Bugloss (Echiitm vulgare). 
Egg. The egg is small in com¬ 
parison to the size of the butterfly, being only 0*65 mm. high 
and of an oval form, with sixteen longitudinal, glassy-white 
fluted keels, very elevated on the crown and decreasing to 
the base ; the spaces between are slightly ribbed transversely. 
At first the colour is light green, which gradually turns to 
smoky-grey-green before emergence of the larva. Finally 
the crown becomes a deep leaden colour from the head of the 
larva showing through the shell. The egg stage lasts about 
seven days, according to the temperature. 
Larva. Upon hatching, the larva eats round the crown 
of the egg, then pushes off the top like a lid, crawls out and 
wanders over the leaf to the under side, where it takes up its 
abode and spins a layer of silk over itself as a covering. 
Under this it lives and feeds on the cuticle of the leaf, leaving 
The Painted Lady 
(Female ab. captured at 
Folkestone, 1872. Tring coll. 
